UNITED STATES DEPARTMENT AGRICULTURE

Rural Utilities Service

**BULLETIN 1753F-201(PC-4)**

**SUBJECT: [RUS Standard for Acceptance Tests and
Measurements]{.underline}**

**[of Telecommunications Plant]{.underline}**

TO: All Telecommunications Borrowers

RUS Telecommunications Staff

**EFFECTIVE DATE:** June 2, 1997.

**EXPIRATION DATE:** Date of change in 7 CFR §§ 1755.400 through
1755.407 by rulemaking.

**OFFICE OF PRIMARY INTEREST:** Outside Plant Branch, Telecommunications
Standards Division.

**PREVIOUS INSTRUCTIONS:** This bulletin replaces RUS Bulletin

345-63, RUS Standard for Acceptance Tests and Measurements of Telephone
Plant, PC-4, issued May 20, 1976.

**FILING INSTRUCTIONS:** Discard RUS Bulletin 345-63, RUS Standard for
Acceptance Tests and Measurements of Telephone Plant, PC-4, dated May
20, 1976, and replace it with this bulletin. File with 7 CFR 1755. This
bulletin is available to the RUS staff on RUSNET (text only) and can be
accessed via Internet at http://www.usda.gov/rus/home/home.htm

**PURPOSE:** This standard covers RUS acceptance tests and measurements
to be performed on installed copper and fiber optic cable
telecommunications plant. This bulletin is a reformat of the text
codified in 7 CFR 1755.400 through 7 CFR 1755.407 published at 62 FR
23958, dated May 2, 1997.

Every effort has been made to ensure the accuracy of this document.
However, in case of discrepancies, the regulations at 7 CFR 1755.400
through 7 CFR 1755.407 are the authorized sources.

Wally Beyer 8/26/97

Administrator Date

**TABLE OF CONTENTS**

CFR to Bulletin Conversion Table \...\...\...\...\...\...\...\.... 6

Abbreviations \...\...\...\...\...\...\...\...\...\...\...\...\...\....
12

Definitions \...\...\...\...\...\...\...\...\...\...\...\...\...\...\...
13

1\. Scope
\...\...\...\...\...\...\...\...\...\...\...\...\...\...\...\...\... 14

2\. Ground Resistance Measurements \...\...\...\...\...\...\...\..... 15

2.1 \...\...\...\...\...\...\...\...\...\...\...\...\...\...\...\.....
15

2.2 \...\...\...\...\...\...\...\...\...\...\...\...\...\...\...\.....
15

2.3 Method of Measurement \...\...\...\...\...\...\...\...\.... 15

2.4 Test Equipment \...\...\...\...\...\...\...\...\...\...\..... 15

2.5 Applicable Results \...\...\...\...\...\...\...\...\...\.... 15

2.6 Data Records \...\...\...\...\...\...\...\...\...\...\...\.... 15

2.7 Probable Causes of Nonconformance \...\...\...\...\.... 16

3\. Copper Cable Telecommunications Plant Measurements \...\... 16

3.1 Shield or Shield/Armor Continuity \...\...\...\...\.... 16

3.2 Conductor Continuity \...\...\...\...\...\...\...\...\..... 21

3.3 DC Insulation Resistance (IR) \...\...\...\...\...\..... 21

3.4 DC Loop Resistance and DC Resistance

Unbalance Measurement \...\...\...\...\...\...\...\...\.... 24

3.5 Subscriber Loop Measurement (Loop Checking) \...\... 26

3.6 One-Person Open Circuit Measurement

(Subscriber Loops) \...\...\...\...\...\...\...\...\...\.... 33

3.7 Carrier Insertion Loss Measurement

(Carrier Frequencies) \...\...\...\...\...\...\...\...\.... 37

4\. Fiber Optic Cable Telecommunications Plant

Measurements \...\...\...\...\...\...\...\...\...\...\...\...\...\.....
40

4.1 Armor Continuity \...\...\...\...\...\...\...\...\...\...\... 40

4.2 Fiber Optic Splice Loss Measurement \...\...\...\..... 41

4.3 End-to-End Attenuation Measurement \...\...\...\...\... 43

4.4 End-to-End Fiber Signature Measurement \...\...\..... 43

5\. Voiceband Data Transmission Measurements \...\...\...\...\.... 44

5.1 Introduction \...\...\...\...\...\...\...\...\...\...\...\.... 44

5.2 Signal-to-C Notched Noise (S/CNN)

Measurement \...\...\...\...\...\...\...\...\...\...\...\..... 44

5.3 Signal-to-Intermodulation Distortion (S/IMD)

Measurement \...\...\...\...\...\...\...\...\...\...\...\..... 45

5.4 Envelope Delay Distortion (EDD) Measurement \...\... 46

5.5 Amplitude Jitter (AJ) Measurement \...\...\...\...\.... 47

5.6 Phase Jitter (PJ) Measurement \...\...\...\...\...\..... 48

5.7 Impulse Noise Measurement \...\...\...\...\...\...\...\... 49

**TABLE OF CONTENTS - Continued**

6\. Shield or Armor Ground Resistance Measurements \...\...\.... 50

6.1 \...\...\...\...\...\...\...\...\...\...\...\...\...\...\...\.....
50

6.2 Method of Measurement \...\...\...\...\...\...\...\...\.... 50

6.3 Test Equipment \...\...\...\...\...\...\...\...\...\...\..... 50

6.4 Applicable Results \...\...\...\...\...\...\...\...\...\.... 50

6.5 Data Record \...\...\...\...\...\...\...\...\...\...\...\..... 51

6.6 Probable Cause for Nonconformance \...\...\...\...\.... 51

7\. Data Formats
\...\...\...\...\...\...\...\...\...\...\...\...\...\..... 52

FORMAT I OUTSIDE PLANT ACCEPTANCE TEST - SUBSCRIBER

LOOPS \...\...\...\...\...\...\...\...\...\...\...\...\... 53

FORMAT II OUTSIDE PLANT ACCEPTANCE TEST - TRUNK

CIRCUITS \...\...\...\...\...\...\...\...\...\...\..... 54

FORMAT III OUTSIDE PLANT ACCEPTANCE TEST - T1 or T1C

CARRIER PAIRS \...\...\...\...\...\...\...\...\..... 55

FORMAT IV OUTSIDE PLANT ACCEPTANCE TEST - STATION

CARRIER PAIRS \...\...\...\...\...\...\...\...\...\... 56

FORMAT V OUTSIDE PLANT ACCEPTANCE TEST - FIBER OPTIC

TELECOMMUNICATIONS PLANT \...\...\...\...\...\..... 57

FORMAT VI VOICEBAND DATA TRANSMISSION - NONLOADED

SUBSCRIBER LOOPS \...\...\...\...\...\...\...\...\... 58

FORMAT VII VOICEBAND DATA TRANSMISSION - TRUNK

CIRCUITS \...\...\...\...\...\...\...\...\...\...\.... 59

**TABLES AND FIGURES**

TABLE 1 Shield Resistance \@68°F (20°C) Cable Diameters

Versus Shield Types (English Units) \...\...\...\...\.... 18

TABLE 2 Shield Resistance \@68°F (20°C) Cable Diameters

Versus Shield Types (Metric Units) \...\...\...\...\..... 19

TABLE 3 DC Loop Resistance \@68°F (20°C) \...\...\...\...\...\..... 25

TABLE 4 Frequency Attenuation \@68°F (20°C) D66 Loaded

Exchange Cables 83 Nanofarads (nF)/mile (52 nF/km) . 29

TABLE 5 Frequency Attenuation \@68°F (20°C) H88 Loaded

Exchange Cables 83 nF/mile (52 nF/km) \...\...\...\..... 30

TABLE 6 Frequency Attenuation \@68°F (20°C) Nonloaded

Exchange Cables 83 nF/mile (52 nF/km) \...\...\...\..... 31

**TABLES AND FIGURES - Continued**

TABLE 7 Cable Attenuation \@68°F (20°C) Filled Cables -

Solid Insulation \...\...\...\...\...\...\...\...\...\...\..... 38

TABLE 8 Cable Attenuation \@68°F (20°C) Filled Cables -

Expanded Insulation \...\...\...\...\...\...\...\...\...\..... 39

FIGURE 1 GROUND RESISTANCE MEASUREMENT \...\...\...\...\...\...\... 60

FIGURE 2 SHIELD OR SHIELD/ARMOR RESISTANCE MEASUREMENT \..... 61

FIGURE 3 DC INSULATION RESISTANCE MEASUREMENT \...\...\...\..... 62

FIGURE 4 DC LOOP RESISTANCE MEASUREMENT \...\...\...\...\...\..... 63

FIGURE 5 DC LOOP RESISTANCE UNBALANCE MEASUREMENT \...\...\.... 64

FIGURE 6 INSERTION LOSS AND FREQUENCY RESPONSE

MEASUREMENT AT SUBSCRIBER LOCATION USING LOOP

CHECKING EQUIPMENT \...\...\...\...\...\...\...\...\...\..... 65

FIGURE 7 NOISE MEASUREMENT AT SUBSCRIBER LOCATION

USING LOOP CHECKING EQUIPMENT \...\...\...\...\...\...\... 66

FIGURE 8 ONE-PERSON OPEN CIRCUIT MEASUREMENT

IMPEDANCE OR PULSE RETURN PATTERN \...\...\...\...\..... 67

FIGURE 9 ONE-PERSON OPEN CIRCUIT MEASUREMENT

RETURN LOSS BALANCED TO ARTIFICIAL LINE \...\...\..... 68

FIGURE 10 ONE-PERSON OPEN CIRCUIT MEASUREMENT

STRUCTURAL RETURN LOSS USING LEVEL TRACER \...\..... 69

FIGURE 11 CARRIER FREQUENCY INSERTION LOSS MEASUREMENT

CABLE FACILITIES \...\...\...\...\...\...\...\...\...\...\... 70

FIGURE 12 EFFECTS OF BRIDGE TAPS ON ATTENUATION \...\...\...\... 71

FIGURE 13 EFFECTS OF LOADING COILS ON ATTENUATION \...\...\.... 72

FIGURE 14 FIBER OPTIC FIELD SPLICE LOSS MEASUREMENT \...\..... 73

FIGURE 15 FIBER OPTIC CENTRAL OFFICE SPLICE

LOSS MEASUREMENT \...\...\...\...\...\...\...\...\...\...\... 74

FIGURE 16 END-TO-END FIBER OPTIC ATTENUATION MEASUREMENT

SHOWING MEASUREMENT IN ONE DIRECTION ONLY \...\..... 75

**TABLES AND FIGURES - Continued**

FIGURE 17 END-TO-END FIBER OPTIC SIGNATURE MEASUREMENT

SHOWING MEASUREMENT IN ONE DIRECTION ONLY \...\..... 76

FIGURE 18 SHIELD OR ARMOR GROUND RESISTANCE MEASUREMENT \.... 77

**INDEX:**

Outside Plant

Construction

Acceptance Testing

Telecommunications

**CFR TO BULLETIN CONVERSION TABLE**

**7 CFR 1755. 400 to 7 CFR 1755.407** **Bulletin 1753F-201**

7 CFR 1755.400 Bulletin Title

7 CFR 1755.401 1.

\(a\) 1.1

(a)(1) 1.1.1\
(a)(2) 1.1.2\
(a)(3) 1.1.3\
(a)(4) 1.1.4\
(a)(5) 1.1.5

\(b\) 1.2\
(c) 1.3\
(d) 1.4\
(e) 1.5

\- 1.6

7 CFR 1755.402 2.

\(a\) 2.1\
(b) 2.2\
(c) 2.3\
(d) 2.4\
(e) 2.5

(e)(1) 2.5.1\
(e)(2) 2.5.2\
(e)(3) 2.5.3

\(f\) 2.6

\(g\) 2.7

7 CFR 1755.403 3.

\(a\) 3.1

(a)(1) 3.1.1\
(a)(2) 3.1.2\
(a)(3) 3.1.3

(a)(3)(i) 3.1.3.1\
(a)(3)(ii) 3.1.3.2

(a)(4) 3.1.4

(a)(4)(i) 3.1.4.1\
(a)(4)(ii) 3.1.4.2

(a)(5) 3.1.5

(a)(5)(i) 3.1.5.1\
(a)(5)(ii) 3.1.5.2\
(a)(5)(iii) 3.1.5.3\
(a)(5)(iv) 3.1.5.4\
(a)(5)(v) 3.1.5.5

(a)(6) 3.1.6\
(a)(7) 3.1.7

\(b\) 3.2\
(c) 3.3

(c)(1) 3.3.1\
(c)(2) 3.3.2

(c)(2)(i) 3.3.2.1\
(c)(2)(ii) 3.3.2.2

(c)(2)(iii) 3.3.2.3

**CFR TO BULLETIN CONVERSION TABLE**

**7 CFR 1755. 400 to 7 CFR 1755.407** **Bulletin 1753F-201**

(c)(3) 3.3.3

(c)(3)(i) 3.3.3.1

(c)(3)(ii) 3.3.3.2

(c)(3)(iii) 3.3.3.3

(c)(4) 3.3.4

(c)(4)(i) 3.3.4.1

(c)(4)(ii) 3.3.4.2

(c)(4)(iii) 3.3.4.3

(c)(4)(iv) 3.3.4.4

(c)(4)(v) 3.3.4.5

(c)(5) 3.3.5

(c)(6) 3.3.6

(c)(6)(i) 3.3.6.1

(c)(6)(ii) 3.3.6.2

(c)(6)(iii) 3.3.6.3

\(d\) 3.4

(d)(1) 3.4.1\
(d)(2) 3.4.2\
(d)(3) 3.4.3\
(d)(4) 3.4.4\
(d)(5) 3.4.5\
(d)(6) 3.4.6

(d)(6)(i) 3.4.6.1\
(d)(6)(ii) 3.4.6.2

(d)(6)(ii)(A) 3.4.6.2.1\
(d)(6)(ii)(B) 3.4.6.2.2\
(d)(6)(ii)(C) 3.4.6.2.3\
(d)(6)(ii)(D) 3.4.6.2.4

(d)(6)(iii) 3.4.6.3\
(d)(6)(iv) 3.4.6.4\
(d)(6)(v) 3.4.6.5\
(d)(6)(vi) 3.4.6.6

(d)(7) 3.4.7\
(d)(8) 3.4.8

\(e\) 3.5

(e)(1) 3.5.1\
(e)(2) 3.5.2\
(e)(3) 3.5.3\
(e)(4) 3.5.4

(e)(4)(i) 3.5.4.1\
(e)(4)(ii) 3.5.4.2

(e)(5) 3.5.5

(e)(5)(i) 3.5.5.1\
(e)(5)(ii) 3.5.5.2

(e)(6) 3.5.6

(e)(6)(i) 3.5.6.1

(e)(6)(i)(A) 3.5.6.1.1\
(e)(6)(i)(B) 3.5.6.1.2

(e)(6)(i)(C) 3.5.6.1.3

**CFR TO BULLETIN CONVERSION TABLE**

**7 CFR 1755. 400 to 7 CFR 1755.407** **Bulletin 1753F-201**

(e)(6)(i)(D) 3.5.6.1.4

(e)(6)(i)(E) 3.5.6.1.5

(e)(6)(i)(F) 3.5.6.1.6

(e)(6)(i)(G) 3.5.6.1.7

(e)(6)(i)(H) 3.5.6.1.8

(e)(6)(ii) 3.5.6.2

(e)(7) 3.5.7\
(e)(8) 3.5.8

(e)(8)(i) 3.5.8.1\
(e)(8)(ii) 3.5.8.2

\(f\) 3.6

(f)(1) 3.6.1\
(f)(2) 3.6.2

(f)(3) 3.6.3\
(f)(4) 3.6.4\
(f)(5) 3.6.5

(f)(5)(i) 3.6.5.1\
(f)(5)(ii) 3.6.5.2\
(f)(5)(iii) 3.6.5.3

(f)(6) 3.6.6\
(f)(7) 3.6.7

(f)(7)(i) 3.6.7.1\
(f)(7)(ii) 3.6.7.2\
(f)(7)(iii) 3.6.7.3\
(f)(7)(iv) 3.6.7.4\
(f)(7)(v) 3.6.7.5\
(f)(7)(vi) 3.6.7.6

(f)(8) 3.6.8

(f)(8)(i) 3.6.8.1

(f)(8)(ii) 3.6 8.2

(f)(9) 3.6.9

\(g\) 3.7

(g)(1) 3.7.1\
(g)(2) 3.7.2\
(g)(3) 3.7.3\
(g)(4) 3.7.4

(g)(4)(i) 3.7.4.1\
(g)(4)(ii) 3.7.4.2\
(g)(4)(iii) 3.7.4.3\
(g)(4)(iv) 3.7.4.4

(g)(5) 3.7.5\
(g)(6) 3.7.6

7 CFR 1755.404 4.

\(a\) 4.1\
(a)(1) 4.1.1

(a)(2) 4.1.2

(a)(3) 4.1.3

(a)(4) 4.1.4

(a)(5) 4.1.5

**CFR TO BULLETIN CONVERSION TABLE**

**7 CFR 1755. 400 to 7 CFR 1755.407** **Bulletin 1753F-201**

(a)(6) 4.1.6

(a)(7) 4.1.7

\(b\) 4.2

(b)(1) 4.2.1

(b)(2) 4.2.2

(b)(2)(i) 4.2.2.1\
(b)(2)(ii) 4.2.2.2

(b)(3) 4.2.3\
(b)(4) 4.2.4

(b)(4)(i) 4.2.4.1\
(b)(4)(ii) 4.2.4.2\
(b)(4)(iii) 4.2.4.3\
(b)(4)(iv) 4.2.4.4\
(b)(4)(v) 4.2.4.5\
(b)(4)(vi) 4.2.4.6

(b)(5) 4.2.5\
(b)(6) 4.2.6

\(c\) 4.3

(c)(1) 4.3.1\
(c)(2) 4.3.2\
(c)(3) 4.3.3\
(c)(4) 4.3.4\
(c)(5) 4.3.5\
(c)(6) 4.3.6

\(d\) 4.4\
(d)(1) 4.4.1\
(d)(2) 4.4.2

(d)(3) 4.4.3

(d)(4) 4.4.4

(d)(5) 4.4.5

(d)(6) 4.4.6

7 CFR 1755.405 5.

\(a\) 5.1

\(b\) 5.2

(b)(1) 5.2.1

(b)(2) 5.2.2

(b)(3) 5.2.3

(b)(4) 5.2.4

(b)(5) 5.2.5

(b)(6) 5.2.6

(b)(7) 5.2.7

\(c\) 5.3

(c)(1) 5.3.1

(c)(2) 5.3.2

(c)(3) 5.3.3

(c)(4) 5.3.4

(c)(5) 5.3.5

(c)(6) 5.3.6

(c)(7) 5.3.7

**CFR TO BULLETIN CONVERSION TABLE**

**7 CFR 1755. 400 to 7 CFR 1755.407** **Bulletin 1753F-201**

(c)(8) 5.3.8

(c)(9) 5.3.9

\(d\) 5.4

(d)(1) 5.4.1

(d)(2) 5.4.2

(d)(3) 5.4.3\
(d)(4) 5.4.4

(d)(5) 5.4.5\
(d)(6) 5.4.6

(d)(7) 5.4.7

(d)(8) 5.4.8

\(e\) 5.5

(e)(1) 5.5.1\
(e)(2) 5.5.2

(e)(3) 5.5.3\
(e)(4) 5.5.4

(e)(5) 5.5.5\
(e)(6) 5.5.6

(e)(7) 5.5.7

(e)(8) 5.5.8

(e)(9) 5.5.9

\(f\) 5.6

(f)(1) 5.6.1\
(f)(2) 5.6.2

(f)(3) 5.6.3\
(f)(4) 5.6.4

(f)(5) 5.6.5\
(f)(6) 5.6.6

(f)(7) 5.6.7

(f)(8) 5.6.8

(f)(9) 5.6.9

\(g\) 5.7

(g)(1) 5.7.1\
(g)(2) 5.7.2

(g)(3) 5.7.3\
(g)(4) 5.7.4

(g)(5) 5.7.5\
(g)(6) 5.7.6

(g)(7) 5.7.7

7 CFR 1755.406 6.

\(a\) 6.1

\(b\) 6.2

(b)(1) 6.2.1

(b)(2) 6.2.2

\(c\) 6.3

(c)(1) 6.3.1

(c)(2) 6.3.2

(c)(3) 6.3.3

(c)(4) 6.3.4

**CFR TO BULLETIN CONVERSION TABLE**

**7 CFR 1755. 400 to 7 CFR 1755.407** **Bulletin 1753F-201**

\(d\) 6.4

(d)(1) 6.4.1\
(d)(2) 6.4.2

(d)(3) 6.4.3\
(d)(4)(i) 6.4.4

(d)(4)(ii) 6.4.5

(d)(5) 6.4.6

\(e\) 6.5

\(f\) 6.6

(f)(1) 6.6.1

(f)(2) 6.6.2

(f)(3) 6.6.3

7 CFR 1755.407 7.

\- 7.1

**ABBREVIATIONS**

ac Alternating current

ANSI American National Standards Institute

AJ Amplitude jitter

AWG American Wire Gauge

°C Centigrade temperature scale

CFSRL Critical Frequency of Structural Return Loss

CO Central office

dB Decibels

dBm0 Decibels relative to one milliwatt, referred to a

zero transmission level point

dBrnc Decibels above Reference Noise C-Message Weighted

dBrnC0 Decibels relative to one picowatt reference noise

level, measured with C-message frequency weighting,

referred to a zero transmission level point

dc Direct current

EED Envelope Delay Distortion

°F Fahrenheit temperature scale

f Frequency

ft Feet

Hz Hertz

IEEE Institute of Electrical and Electronic Engineers

IMD Intermodulation Distortion

in. Inches

IR Insulation resistance

kHz Kilohertz

km Kilometer

m Meter

Mb/s Megabit per second

MDF Main Distributing Frame

MGB Master Ground Bar

mm Millimeter

nF Nanofarad

NID Network interface device

NM Circuit noise

OTDR Optical time domain reflectometer

\% Percent

°p-p Degrees peak-to-peak

PBN Precision balance network

PI Power influence

PJ Phase jitter

RED Relative Envelope Delay

RST Remote Switching Terminal

RUS Rural Utilities Service

S/CNN Signal-to-C-Notched Noise

S/IMD Signal-to-Intermodulation Delay

SRL Structural return loss

TE&CM Telecommunications Engineering and Construction Manual

UI Unit interval

**DEFINITIONS**

**[Amplitude Jitter]{.underline}:** A measurement of any fluctuation in
the peak amplitude value of a fixed tone signal at 1,004 Hz from its
nominal value.

**[C-Message Weighted]{.underline}:** A weighting derived from listening
tests, to indicate the relative annoyance or speech impairment by an
interfering signal of frequency (f) as heard through a "500-type"
telephone set.

**[Envelope Delay Distortion]{.underline}:** A measure of the linearity
or uniformity of the phase versus frequency characteristics of a
transmission facility.

**[D66 Loading]{.underline}:** A specific loading scheme using a 66
millihenry inductor spaced nominally at 4,500 ft (1,371 m) intervals.

**[H88 Loading]{.underline}:** A specific loading scheme using an 88
millihenry inductor spaced nominally at 6,000 ft (1,829 m) intervals.

**[Impulse Noise]{.underline}:** A measurement of the presence of
unusually large noise excursions of short duration that are beyond the
normal background noise levels on a facility.

**[Phase Jitter]{.underline}:** A measure of any fluctuation in the zero
crossings of a fixed tone signal (usually 1,004 Hz) from their nominal
position in time within the voiceband.

**[Signal-to-C Notched Noise]{.underline}:** A logarithmic ratio
expressed in dB of a 1,004 Hz holding tone signal compared to C-message
weighted noise level.

**[Signal-to-Intermodulation Distortion]{.underline}:** A measure of the
distortion produced by extraneous frequency cross products, known as
intermodulation products, when a multi-tone signal is applied to a
system.

**[T1 Digital Carrier]{.underline}:** A 24 channel 1.544 megabit per
second (Mb/s) pulse code modulation system.

**[T1C Digital Carrier]{.underline}:** A 48 channel 3.152 Mb/s pulse
code modulation system.

**1. SCOPE**

**1.1** Acceptance tests outlined in this bulletin are applicable to
plant constructed by contract or force account. This testing standard
provides for the following:

**1.1.1** Specific types of tests or measurements for the different
types of telecommunications plant and equipment;

**1.1.2** The method of measurement and types of measuring equipment;

**1.1.3** The expected results and tolerances permitted to meet the
acceptable standards and objectives;

**1.1.4** Suggested formats for recording the results of the
measurements and tests; and

**1.1.5** Some probable causes of nonconformance and methods for
corrective action, where possible.

**1.2** Alternative methods of measurements that provide suitable
alternative results shall be permitted with the concurrence of the Rural
Utilities Service (RUS).

**1.3** For the purpose of this testing standard, a \"measurement\"
shall be defined as an evaluation where quantitative data is obtained
(e.g., resistance in ohms, structural return loss in decibels (dB),
etc.) and a \"test\" shall be defined as an evaluation where no
quantitative data is obtained (e.g., a check mark indicating conformance
is usually the result of the test).

**1.4** The sequence of tests and measurements described in this
standard have been prepared as a guide. Variations from the sequence may
be necessary on an individual application basis.

**1.5** There is some overlap in the methods of testing shown; also, the
extent of each phase of testing may vary on an individual basis. The
borrower shall determine the overall plan of testing, the need and
extent of testing, and the responsibility for each phase of testing.

**1.6** Copies of the American National Standards Institute (ANSI)
T1.506-1990, "American National Standard for Telecommunications -
Network Performance - Transmission Specifications for Switched Exchange
Access Network," including supplement ANSI T1.506a-1992, and American
National Standards Institute/Institute of Electrical and Electronics
Engineers (ANSI/IEEE) 743-1984, "IEEE Standard Methods and Equipment for
Measuring the Transmission Characteristics of Analog Voice Frequency
Circuits," referenced in this standard can both be obtained for nominal
fees at the address indicated below:

ANSI, Customer Service

11 West 42nd Street

New York, New York 10036

Telephone No. (212) 642-4900

**2. GROUND RESISTANCE MEASUREMENTS**

**2.1** The resistance of the central office (CO) and the remote
switching terminal (RST) ground shall be measured before and after it
has been bonded to the master ground bar (MGB) where it is connected to
the building electric service ground.

**2.2** The ground resistance of electronic equipment such as span line
repeaters, carrier terminal equipment, concentrators, etc. shall be
measured.

**[2.3 Method of Measurement]{.underline}:** The connection of test
equipment for the ground resistance measurement shall be as shown in
Figure 1. Refer to RUS Bulletin 1751F-802, \"Electrical Protection
Grounding Fundamentals,\" for a comprehensive discussion of ground
resistance measurements.

**2.4 [Test Equipment]{.underline}:** The test equipment for making this
measurement is shown in Figure 1.

**2.5 [Applicable Results]{.underline}:**

**2.5.1** For the CO and RST, the resistance after the bond has been
made to the MGB electric service ground shall not exceed 5 ohms. Where
the measured ground resistance exceeds 5 ohms, the borrower shall
determine what additional grounding, if any, shall be provided.

**2.5.2** For electronic equipment, the ground resistance shall not
exceed 25 ohms. Where the measured ground resistance exceeds 25 ohms,
the borrower shall determine what additional grounding, if any, shall be
provided.

**2.5.3** When ground resistance measurements exceed the ground
resistance requirements of Paragraphs 2.5.1 and 2.5.2 of this bulletin,
refer to RUS Bulletin 1751F-802, \"Electrical Protection Grounding
Fundamentals,\" for suggested methods of reducing the ground resistance.

**2.6 [Data Record]{.underline}:** Results of the CO and RST ground
resistance measurements shall be recorded. A suggested format similar to
Format I, Outside Plant Acceptance Tests - Subscriber Loops, in
Paragraph 7 of this bulletin or a format specified in the applicable
construction contract may be used. Results of the electronic equipment
ground resistance measurements shall be recorded. A suggested format
similar to Format II, Outside Plant Acceptance Tests - Trunk Circuits,
in Paragraph 7 of this bulletin or a format specified in the applicable
construction contract may be used. Data showing approximate moisture
content of the soil at the time of measurement, the temperature, the
type of soil and a description of the test equipment used shall also be
included.

**2.7 [Probable Causes of Nonconformance]{.underline}:** Refer to RUS
Bulletin 1751F-802, \"Electrical Protection Grounding Fundamentals,\"
and Telecommunications Engineering and Construction Manual (TE&CM)
Section 810, \"Electrical Protection of Electronic Analog and Digital
Central Office Equipment,\" for possible causes of nonconformance and
suggested methods for corrective action.

**3. COPPER CABLE TELECOMMUNICATIONS PLANT MEASUREMENTS**

**3.1 [Shield or Shield/Armor Continuity]{.underline}:**

**3.1.1** Tests and measurements shall be made to ensure that cable
shields or shield/armors are electrically continuous. There are two
areas of concern. The first is shield or shield/armor bonding within a
pedestal or splice and the second is shield or shield/armor continuity
between pedestals or splices.

**3.1.2** Measurement techniques outlined here for verification of
shield or shield/armor continuity are applicable to buried cable plant.
Measurements of shield continuity between splices in aerial cable plant
should be made prior to completion of splicing. Conclusive results
cannot be obtained on aerial plant after all bonds have been completed
to the supporting strand, multigrounded neutral, etc.

**3.1.3** **[Method of Measurement]{.underline}:**

**3.1.3.1** The shield or shield/armor resistance measurements shall be
made between pedestals or splices using either a Wheatstone bridge or a
volt-ohm meter. For loaded plant, measurements shall be made on cable
lengths that do not exceed one load section. For nonloaded plant,
measurements shall be made on cable lengths that do not exceed 5,000
feet (ft) (1,524 meters (m)). All bonding wires shall be removed from
the bonding lugs at the far end of the cable section to be measured. The
step-by-step measurement procedure shall be as shown in Figure 2.

**3.1.3.2** Cable shield or shield/armor continuity within pedestals or
splices shall be measured with a cable shield splice continuity test
set. The step-by-step measurement procedure outlined in the
manufacturer\'s operating instructions for the specific test equipment
being used shall be followed.

**3.1.4** **[Test Equipment]{.underline}:**

**3.1.4.1** The test equipment for measuring cable shield or
shield/armor resistance between pedestals or splices is shown in Figure
2.

**3.1.4.2** A cable shield splice continuity tester shall be used to
measure shield or shield/armor continuity within pedestals or splices.

**3.1.5 [Applicable Results]{.underline}:**

**3.1.5.1** The shield or shield/armor resistance per 1000 ft and per
kilometer (km) for cable diameters and types of shielding materials are
given in Table 1 (English Units) and Table 2 (Metric Units),
respectively as follows:

+------------------+-------+-------+-------+-------+-------+---------+
| Table 1 - Shield |       |       |       |       |       |         |
| Resistance @     |       |       |       |       |       |         |
| 68°F (20°C)      |       |       |       |       |       |         |
|                  |       |       |       |       |       |         |
| Cable Diameters  |       |       |       |       |       |         |
| Versus Shield    |       |       |       |       |       |         |
| Types            |       |       |       |       |       |         |
|                  |       |       |       |       |       |         |
| (English Units)  |       |       |       |       |       |         |
+------------------+-------+-------+-------+-------+-------+---------+
| Outside Diameter | No    |       |       |       |       |         |
|                  | minal |       |       |       |       |         |
|                  | Resis |       |       |       |       |         |
|                  | tance |       |       |       |       |         |
|                  | ohm   |       |       |       |       |         |
|                  | /1000 |       |       |       |       |         |
|                  | ft    |       |       |       |       |         |
+------------------+-------+-------+-------+-------+-------+---------+
| Inches (in.)     | A     | B     | C     | D     | E     | F       |
+------------------+-------+-------+-------+-------+-------+---------+
| 0.40 - 0.49      | 0.77  | 1.54  | 1.65  | 1.96  | 2.30  | 5.51    |
+------------------+-------+-------+-------+-------+-------+---------+
| 0.50 - 0.59      | 0.64  | 1.28  | 1.37  | 1.63  | 1.91  | 4.58    |
+------------------+-------+-------+-------+-------+-------+---------+
| 0.60 - 0.69      | 0.51  | 1.03  | 1.10  | 1.31  | 1.53  | 3.67    |
+------------------+-------+-------+-------+-------+-------+---------+
| 0.70 - 0.79      | 0.44  | 0.88  | 0.94  | \-    | 1.31  | 3.14    |
+------------------+-------+-------+-------+-------+-------+---------+
| 0.80 - 0.89      | 0.38  | 0.77  | 0.82  | \-    | 1.14  | 2.74    |
+------------------+-------+-------+-------+-------+-------+---------+
| 0.90 - 0.99      | 0.35  | 0.69  | 0.74  | \-    | 1.03  | 2.47    |
+------------------+-------+-------+-------+-------+-------+---------+
| 1.00 - 1.09      | 0.31  | 0.62  | 0.66  | \-    | 0.92  | 2.20    |
+------------------+-------+-------+-------+-------+-------+---------+
| 1.10 - 1.19      | 0.28  | 0.56  | 0.60  | \-    | 0.84  | 2.00    |
+------------------+-------+-------+-------+-------+-------+---------+
| 1.20 - 1.29      | 0.26  | 0.51  | 0.55  | \-    | 0.77  | 1.84    |
+------------------+-------+-------+-------+-------+-------+---------+
| 1.30 - 1.39      | 0.24  | 0.48  | 0.51  | \-    | 0.71  | 1.70    |
+------------------+-------+-------+-------+-------+-------+---------+
| 1.40 - 1.49      | 0.22  | 0.44  | 0.47  | \-    | 0.65  | 1.57    |
+------------------+-------+-------+-------+-------+-------+---------+
| 1.50 - 1.59      | 0.21  | 0.41  | 0.44  | \-    | 0.61  | 1.47    |
+------------------+-------+-------+-------+-------+-------+---------+
| 1.60 - 1.69      | 0.19  | 0.38  | 0.41  | \-    | 0.57  | 1.37    |
+------------------+-------+-------+-------+-------+-------+---------+
| 1.70 - 1.79      | 0.18  | 0.37  | 0.39  | \-    | 0.54  | 1.30    |
+------------------+-------+-------+-------+-------+-------+---------+
| 1.80 - 1.89      | 0.17  | 0.35  | 0.37  | \-    | 0.51  | 1.24    |
+------------------+-------+-------+-------+-------+-------+---------+
| 1.90 - 1.99      | 0.16  | 0.33  | 0.35  | \-    | 0.49  | 1.17    |
+------------------+-------+-------+-------+-------+-------+---------+
| 2.00 - 2.09      | 0.15  | 0.31  | 0.33  | \-    | 0.46  | 1.10    |
+------------------+-------+-------+-------+-------+-------+---------+
| 2.10 - 2.19      | 0.15  | 0.29  | 0.31  | \-    | 0.43  | 1.03    |
+------------------+-------+-------+-------+-------+-------+---------+
| 2.20 - 2.29      | 0.14  | 0.28  | 0.30  | \-    | 0.42  | 1.00    |
+------------------+-------+-------+-------+-------+-------+---------+
| 2.30 - 2.39      | 0.14  | 0.27  | 0.29  | \-    | 0.40  | 0.97    |
+------------------+-------+-------+-------+-------+-------+---------+
| 2.40 - 2.49      | 0.13  | 0.25  | 0.27  | \-    | 0.38  | 0.90    |
+------------------+-------+-------+-------+-------+-------+---------+
| 2.50 - 2.59      | 0.12  | 0.24  | 0.26  | \-    | 0.36  | 0.87    |
+------------------+-------+-------+-------+-------+-------+---------+
| 2.60 - 2.69      | 0.12  | 0.23  | 0.25  | \-    | 0.35  | 0.83    |
+------------------+-------+-------+-------+-------+-------+---------+
| 2.70 - 2.79      | 0.11  | 0.22  | 0.24  | \-    | 0.33  | 0.80    |
+------------------+-------+-------+-------+-------+-------+---------+
| 2.80 - 2.89      | 0.11  | 0.22  | 0.24  | \-    | 0.33  | 0.80    |
+------------------+-------+-------+-------+-------+-------+---------+
| 2.90 - 2.99      | 0.11  | 0.22  | 0.23  | \-    | 0.32  | 0.77    |
+------------------+-------+-------+-------+-------+-------+---------+
| 3.00 - 3.09      | 0.10  | 0.21  | 0.22  | \-    | 0.31  | 0.73    |
+------------------+-------+-------+-------+-------+-------+---------+
| 3.10 - 3.19      | 0.10  | 0.20  | 0.21  | \-    | 0.29  | 0.70    |
+------------------+-------+-------+-------+-------+-------+---------+
| 3.20 - 3.29      | 0.10  | 0.20  | 0.21  | \-    | 0.29  | 0.70    |
+------------------+-------+-------+-------+-------+-------+---------+
| 3.30 - 3.39      | 0.09  | 0.19  | 0.20  | \-    | 0.28  | 0.67    |
+------------------+-------+-------+-------+-------+-------+---------+
| 3.40 - 3.49      | 0.09  | 0.18  | 0.19  | \-    | 0.26  | 0.63    |
+------------------+-------+-------+-------+-------+-------+---------+
| 3.50 - 3.59      | 0.09  | 0.18  | 0.19  | \-    | 0.26  | 0.63    |
+------------------+-------+-------+-------+-------+-------+---------+
| 3.60 - 3.69      | 0.08  | 0.17  | 0.18  | \-    | 0.25  | 0.60    |
+------------------+-------+-------+-------+-------+-------+---------+
| 3.70 - 3.79      | 0.08  | 0.17  | 0.18  | \-    | 0.25  | 0.60    |
+------------------+-------+-------+-------+-------+-------+---------+
| 3.80 - 3.89      | 0.08  | 0.16  | 0.17  | \-    | 0.24  | 0.57    |
+------------------+-------+-------+-------+-------+-------+---------+
| 3.90 - 3.99      | 0.08  | 0.16  | 0.17  | \-    | 0.24  | 0.57    |
+------------------+-------+-------+-------+-------+-------+---------+
| 4.00 - 4.99      | 0.07  | 0.15  | 0.16  | \-    | 0.22  | 0.53    |
+------------------+-------+-------+-------+-------+-------+---------+

Where: Column A - 10 mil Copper shield.

Column B - 5 mil Copper shield.

Column C - 8 mil Coated Aluminum and 8 mil Coated

Aluminum/6 mil Coated Steel shields.

Column D - 7 mil Alloy 194 shield.

Column E - 6 mil Alloy 194 and 6 mil Copper Clad

Stainless Steel shields.

Column F - 5 mil Copper Clad Stainless Steel and

5 mil Copper Clad Alloy Steel shields.

+-------------------+-------+-------+-------+-------+-------+--------+
| Table 2 - Shield  |       |       |       |       |       |        |
| Resistance @ 68°F |       |       |       |       |       |        |
| (20°C)            |       |       |       |       |       |        |
|                   |       |       |       |       |       |        |
| Cable Diameters   |       |       |       |       |       |        |
| Versus Shield     |       |       |       |       |       |        |
| Types             |       |       |       |       |       |        |
|                   |       |       |       |       |       |        |
| (Metric Units)    |       |       |       |       |       |        |
+-------------------+-------+-------+-------+-------+-------+--------+
| Outside Diameter  | No    |       |       |       |       |        |
|                   | minal |       |       |       |       |        |
|                   | Resis |       |       |       |       |        |
|                   | tance |       |       |       |       |        |
|                   | o     |       |       |       |       |        |
|                   | hm/km |       |       |       |       |        |
+-------------------+-------+-------+-------+-------+-------+--------+
| Millimeters (mm)  | A     | B     | C     | D     | E     | F      |
+-------------------+-------+-------+-------+-------+-------+--------+
| 10.2 - 12.5       | 2.53  | 5.05  | 5.41  | 6.43  | 7.55  | 18.08  |
+-------------------+-------+-------+-------+-------+-------+--------+
| 12.7 - 15.0       | 2.10  | 4.20  | 4.49  | 5.35  | 6.27  | 15.03  |
+-------------------+-------+-------+-------+-------+-------+--------+
| 15.2 - 17.5       | 1.67  | 3.38  | 3.61  | 4.30  | 5.02  | 12.04  |
+-------------------+-------+-------+-------+-------+-------+--------+
| 17.8 - 20.1       | 1.44  | 2.89  | 3.08  | \-    | 4.30  | 10.30  |
+-------------------+-------+-------+-------+-------+-------+--------+
| 20.3 - 22.6       | 1.25  | 2.53  | 2.69  | \-    | 3.74  | 8.99   |
+-------------------+-------+-------+-------+-------+-------+--------+
| 22.9 - 25.1       | 1.15  | 2.26  | 2.43  | \-    | 3.38  | 8.10   |
+-------------------+-------+-------+-------+-------+-------+--------+
| 25.4 - 27.7       | 1.02  | 2.03  | 2.16  | \-    | 3.02  | 7.22   |
+-------------------+-------+-------+-------+-------+-------+--------+
| 27.9 - 30.2       | 0.92  | 1.84  | 1.97  | \-    | 2.76  | 6.56   |
+-------------------+-------+-------+-------+-------+-------+--------+
| 30.5 - 32.8       | 0.85  | 1.67  | 1.80  | \-    | 2.53  | 6.04   |
+-------------------+-------+-------+-------+-------+-------+--------+
| 33.0 - 35.3       | 0.79  | 1.57  | 1.67  | \-    | 2.33  | 5.58   |
+-------------------+-------+-------+-------+-------+-------+--------+
| 35.6 - 37.8       | 0.72  | 1.44  | 1.54  | \-    | 2.13  | 5.15   |
+-------------------+-------+-------+-------+-------+-------+--------+
| 38.1 - 40.4       | 0.69  | 1.34  | 1.44  | \-    | 2.00  | 4.82   |
+-------------------+-------+-------+-------+-------+-------+--------+
| 40.6 - 42.9       | 0.62  | 1.25  | 1.34  | \-    | 1.87  | 4.49   |
+-------------------+-------+-------+-------+-------+-------+--------+
| 43.2 - 45.5       | 0.59  | 1.21  | 1.28  | \-    | 1.77  | 4.26   |
+-------------------+-------+-------+-------+-------+-------+--------+
| 45.7 - 48.0       | 0.56  | 1.15  | 1.21  | \-    | 1.67  | 4.07   |
+-------------------+-------+-------+-------+-------+-------+--------+
| 48.3 - 50.5       | 0.52  | 1.08  | 1.15  | \-    | 1.61  | 3.84   |
+-------------------+-------+-------+-------+-------+-------+--------+
| 50.8 - 53.1       | 0.49  | 1.02  | 1.08  | \-    | 1.51  | 3.61   |
+-------------------+-------+-------+-------+-------+-------+--------+
| 53.3 - 55.6       | 0.49  | 0.95  | 1.02  | \-    | 1.41  | 3.38   |
+-------------------+-------+-------+-------+-------+-------+--------+
| 55.9 - 58.2       | 0.46  | 0.92  | 0.98  | \-    | 1.38  | 3.28   |
+-------------------+-------+-------+-------+-------+-------+--------+
| 58.4 - 60.7       | 0.46  | 0.89  | 0.95  | \-    | 1.31  | 3.18   |
+-------------------+-------+-------+-------+-------+-------+--------+
| 61.0 - 63.2       | 0.43  | 0.82  | 0.89  | \-    | 1.25  | 2.95   |
+-------------------+-------+-------+-------+-------+-------+--------+
| 63.5 - 65.8       | 0.39  | 0.79  | 0.85  | \-    | 1.18  | 2.85   |
+-------------------+-------+-------+-------+-------+-------+--------+
| 66.0 - 68.3       | 0.39  | 0.75  | 0.82  | \-    | 1.15  | 2.72   |
+-------------------+-------+-------+-------+-------+-------+--------+
| 68.6 - 70.9       | 0.36  | 0.72  | 0.79  | \-    | 1.08  | 2.62   |
+-------------------+-------+-------+-------+-------+-------+--------+
| 71.1 - 73.4       | 0.36  | 0.72  | 0.79  | \-    | 1.08  | 2.62   |
+-------------------+-------+-------+-------+-------+-------+--------+
| 73.7 - 75.9       | 0.36  | 0.72  | 0.75  | \-    | 1.05  | 2.53   |
+-------------------+-------+-------+-------+-------+-------+--------+
| 76.2 - 78.5       | 0.33  | 0.69  | 0.72  | \-    | 1.02  | 2.39   |
+-------------------+-------+-------+-------+-------+-------+--------+
| 78.7 - 81.0       | 0.33  | 0.66  | 0.69  | \-    | 0.95  | 2.30   |
+-------------------+-------+-------+-------+-------+-------+--------+
| 81.3 - 83.6       | 0.33  | 0.66  | 0.69  | \-    | 0.95  | 2.30   |
+-------------------+-------+-------+-------+-------+-------+--------+
| 83.6 - 86.1       | 0.29  | 0.62  | 0.66  | \-    | 0.92  | 2.20   |
+-------------------+-------+-------+-------+-------+-------+--------+
| 86.4 - 88.6       | 0.29  | 0.59  | 0.62  | \-    | 0.85  | 2.07   |
+-------------------+-------+-------+-------+-------+-------+--------+
| 88.9 - 91.2       | 0.29  | 0.59  | 0.62  | \-    | 0.85  | 2.07   |
+-------------------+-------+-------+-------+-------+-------+--------+
| 91.4 - 93.7       | 0.26  | 0.56  | 0.59  | \-    | 0.82  | 1.97   |
+-------------------+-------+-------+-------+-------+-------+--------+
| 94.0 - 96.3       | 0.26  | 0.56  | 0.59  | \-    | 0.82  | 1.97   |
+-------------------+-------+-------+-------+-------+-------+--------+
| 96.5 - 98.8       | 0.26  | 0.52  | 0.56  | \-    | 0.79  | 1.87   |
+-------------------+-------+-------+-------+-------+-------+--------+
| 99.1 - 101.3      | 0.26  | 0.52  | 0.56  | \-    | 0.79  | 1.87   |
+-------------------+-------+-------+-------+-------+-------+--------+
| 101.6 - 103.9     | 0.23  | 0.49  | 0.52  | \-    | 0.72  | 1.74   |
+-------------------+-------+-------+-------+-------+-------+--------+

Where: Column A - 10 mil Copper shield.

Column B - 5 mil Copper shield.

Column C - 8 mil Coated Aluminum and 8 mil Coated

Aluminum/6 mil Coated Steel shields.

Column D - 7 mil Alloy 194 shield.

Column E - 6 mil Alloy 194 and 6 mil Copper Clad

Stainless Steel shields.

Column F - 5 mil Copper Clad Stainless Steel and

5 mil Copper Clad Alloy Steel shields.

**3.1.5.2** All values of shield and shield/armor resistance provided in
Tables 1 and 2 in Paragraph 3.1.5.1 of this bulletin are considered
approximations. If the measured value corrected to 68°F (20°C) is within
± 30 percent (%) of the value shown in Table 1 or 2, the shield and
shield/armor shall be assumed to be continuous.

**3.1.5.3** To correct the measured shield resistance to the reference
temperature of 68°F (20°C) use the following formulae:

R~68~ = R~t~ / \[1 + A(t - 68)\] for English Units

R~20~ = R~t~ / \[1 + A(t - 20)\] for Metric Units

Where:

R~68~ = Shield resistance corrected to 68°F in ohms.

R~20~ = Shield resistance corrected to 20°C in ohms.

R~t~ = Shield resistance at measurement temperature

in ohms.

A = Temperature coefficient of the shield tape.

t = Measurement temperature in °F or (°C).

**3.1.5.4** The temperature coefficients (A) for the shield tapes to be
used in the formulae referenced in Paragraph 3.1.5.3 of this bulletin
are as follows:

a\. 5 and 10 mil copper = 0.0021 for English units and

0.0039 for Metric units;

b\. 8 mil coated aluminum and 8 mil coated aluminum/6 mil

coated steel = 0.0022 for English units and 0.0040 for

Metric units;

c\. 5 mil copper clad stainless steel and 5 mil copper clad

alloy steel = 0.0024 for English units and 0.0044 for

Metric units;

d\. 6 mil copper clad stainless steel = 0.0019 for English

units and 0.0035 for Metric units; and

e\. 6 and 7 mil alloy 194 = 0.0013 for English units and

0.0024 for Metric units.

**3.1.5.5** When utilizing shield continuity testers to measure shield
and shield/armor continuity within pedestals or splices, refer to the
manufacturer\'s published information covering the specific test
equipment to be used and for anticipated results.

**3.1.6** **[Data Record]{.underline}:** Measurement data from shield
continuity tests shall be recorded together with anticipated Table 1 or
2 values (see Paragraph 3.1.5.1 of this bulletin) in an appropriate
format to permit comparison. The recorded data shall include specific
location, cable size, cable type, type of shield or shield/armor, if
known, etc.

**3.1.7** **[Probable Causes for Nonconformance]{.underline}:** Among
probable causes for nonconformance are broken or damaged shields or
shield/armors, bad bonding harnesses, poorly connected bonding clamps,
loose bonding lugs, etc.

**3.2 [Conductor Continuity]{.underline}:** After placement of all cable
and wire plant has been completed and joined together in continuous
lengths, tests shall be made to ascertain that all pairs are free from
grounds, shorts, crosses, and opens, except for those pairs indicated as
being defective by the cable manufacturer. The tests for grounds,
shorts, crosses, and opens are not separate tests, but are inherent in
other acceptance tests discussed in this section. The test for grounds,
shorts, and crosses is inherent when conductor insulation resistance
measurements are conducted per Paragraph 3.3 of this bulletin, while
tests for opens are inherent when tests are conducted for loop
resistance, insertion loss, noise, or return loss measurements, per
Paragraphs 3.4, 3.5, or 3.6 of this bulletin. The borrower shall make
certain that all defective pairs are corrected, except those noted as
defective by the cable manufacturer in accordance with the marking
provisions of the applicable cable and wire specifications. All
defective pairs that are not corrected shall be reported in writing with
details of the corrective measures attempted.

**3.3 [DC Insulation Resistance (IR) Measurement]{.underline}:**

**3.3.1** IR measurements shall be made on completed lengths of
insulated cable and wire plant.

**3.3.2 [Method of Measurement]{.underline}:**

**3.3.2.1** The IR measurement shall be made between each conductor and
all other conductors, sheath, shield and/or shield/armor, and/or support
wire electrically connected together and to the main distributing frame
(MDF) ground. The measurement shall be made from the central office with
the entire length of the cable under test and, where used with all
protectors and load coils connected. For COs containing solid state
arresters, the solid state arresters shall be removed before making the
IR measurements. Field mounted voice frequency repeaters, where used,
may be left connected for the IR test but all carrier frequency
equipment, including carrier repeaters and terminals, shall be
disconnected. Pairs used to feed power remote from the

CO shall have the power disconnected and the tip and ring conductors
shall be opened before making IR tests. All conductors shall be opened
at the far end of the cable being measured.

**3.3.2.2** IR tests are normally made from the MDF with all CO
equipment disconnected at the MDF, but this test may be made on new
cables at field locations before they are spliced to existing cables.
The method of measurement shall be as shown in Figure 3.

**3.3.2.3** If the IR of the conductor cannot be measured because of
breakdown of lightning arresters by the test voltage, the arrester units
shall be removed and the conductor IR retested. If the IR then meets the
minimum requirements, the conductor will be considered satisfactory.
Immediately following the IR tests, all arrester units which have been
removed shall be reinstalled.

**3.3.3 [Test Equipment]{.underline}:**

**3.3.3.1** IR measurements shall be made with either an insulation
resistance test set or a direct current (dc) bridge type megohmmeter.

**3.3.3.2** The IR test set shall have an output voltage not to exceed
500 volts dc and shall be of the hand cranked or battery operated type.

**3.3.3.3** The dc bridge type megohmmeter, which may be alternating
current (ac) powered, shall have scales and multiplier which make it
possible to accurately read IR from 1 megohm to 1 gigohm. The voltage
applied to the conductors under test shall not exceed \"250 volts dc\"
when using an instrument having adjustable test voltage levels. This
will help to prevent breakdown of lightning arresters.

**3.3.4 [Applicable Results]{.underline}:**

**3.3.4.1** For all new insulated cable or wire facilities, the expected
IR levels are normally greater than 1,000 to 2,000 megohm-mile (1,609 to
3,218 megohm-km). A value of 500 megohm-mile (805 megohm-km) at 68°F
(20°C) shall be the minimum acceptable value of IR. IR varies inversely
with the length and the temperature.

**3.3.4.2** The megohm-mile (megohm-km) value for a conductor may be
computed by multiplying the actual scale reading in megohms on the test
set by the length in miles (km) of the conductor under test.

**3.3.4.3** The objective insulation resistance may be determined by
dividing 500 by the length in miles (805 by the length in km) of the
cable or wire conductor being tested. The resulting value shall be the
minimum acceptable meter scale reading in megohms.

**3.3.4.4** Due to the differences between various insulating materials
and filling compounds used in manufacturing cable or wire, it is
impractical to provide simple factors to predict the magnitude of
variation in insulation resistance due to temperature. The variation
can, however, be substantial for wide excursions in temperature from the
ambient temperature of 68°F (20°C).

**3.3.4.5** Borrowers should be certain that tip and ring IR
measurements of each pair are approximately the same. Borrowers should
also be certain that IR measurements are similar for cable or wire
sections of similar length and cable or wire type. If some pairs measure
significantly lower, borrowers should attempt to improve these pairs in
accordance with cable manufacturer's recommendations. (Note: Only the
megohm-mile (megohm-km) requirement shall be cause for rejection, not
individual measurement differences.)

**3.3.5 [Data Record]{.underline}:** The measurement data shall be
recorded. Suggested formats similar to Format I, Outside Plant
Acceptance Tests - Subscriber Loops, or Format II, Outside Plant
Acceptance Tests - Trunk Circuits, in Paragraph 7 of this bulletin or
formats specified in the applicable construction contract may be used.

**3.3.6 [Probable Causes for Nonconformance]{.underline}:**

**3.3.6.1** When an IR measurement is below 500 megohm-mile (805
megohm-km), the cable or wire temperature at the time of testing must
then be taken into consideration. If this temperature is well above 68°F
(20°C), the measurement shall be disregarded and the cable or wire shall
be remeasured at a time when the temperature is approximately 68°F
(20°C). If the result is then 500 megohm-mile (805 megohm-km) or
greater, the cable or wire shall be considered satisfactory.

**3.3.6.2** Should the cable or wire fail to meet the 500 megohm-mile
(805 megohm-km) requirement when the temperature is known to be
approximately 68°F (20°C) there is not yet justification for rejection
of the cable or wire. Protectors, lightning arresters, etc., may be a
source of low insulation resistance. These devices shall be removed from
the cable or wire and the cable or wire IR measurement shall be
repeated. If the result is acceptable, the cable or wire shall be
considered acceptable. The removed devices which caused the low
insulation resistance value shall be identified and replaced, if found
defective.

**3.3.6.3** When the cable or wire alone is still found to be below the
500 megohm-mile (805 megohm-km) requirement after completing the steps
in Paragraph 3.3.6.1 and/or Paragraph 3.3.6.2 of this bulletin, the test
shall be repeated to measure the cable or wire in sections to isolate
the piece(s) of cable or wire responsible. The cable or wire section(s)
that is found to be below the 500

megohm-mile (805 megohm-km) requirement shall be either repaired in
accordance with the cable or wire manufacturer\'s recommended procedure
or shall be replaced as directed by the borrower.

**3.4 [DC Loop Resistance and DC Resistance Unbalance
Measurement]{.underline}:**

**3.4.1** When specified by the borrower, dc loop resistance and dc
resistance unbalance measurements shall be made on all cable pairs used
as trunk circuits. The dc loop resistance and dc resistance unbalance
measurements shall be made between CO locations. Measurements shall
include all components of the cable path.

**3.4.2** Dc loop resistance and dc resistance unbalance measurements
shall be made on all cable pairs used as subscriber loop circuits when:

a\. Specified by the borrower;

b\. A large number of long loops terminate at one location

(similar to trunk circuits); or

c\. Circuit balance is less than 60 dB when computed from

noise measurements as described in Paragraph 3.5 of

this bulletin.

**3.4.3** Dc resistance unbalance is controlled to the maximum possible
degree by the cable specification. Allowable random unbalance is
specified between tip and ring conductors within each reel. Further
random patterns should occur when the cable conductor size changes.
Cable meeting the unbalance requirements of the cable specification may
under some conditions result in of the cable specification may under
some conditions result in unacceptable noise levels as discussed in
Paragraph 3.4.6.3 of this bulletin.

**3.4.4 [Method of Measurement]{.underline}:** The method of measurement
shall be as detailed in Figures 4 and 5.

**3.4.5 [Test Equipment]{.underline}:** The test equipment is shown in

Figures 4 and 5.

**3.4.6 [Applicable Results]{.underline}:**

**3.4.6.1** The measured dc loop resistance shall be within ± 5% of the
calculated dc loop resistance when corrected for temperature.

**3.4.6.2** The calculated dc loop resistance is computed as follows:

**3.4.6.2.1** Multiply the length of each different gauge by the
applicable resistance per unit length as shown in Table 3 as follows:

  --------------------------------- ------------------ ------------------
  Table 3 - DC Loop Resistance @                       
  68°F (20°C)                                          

                                    Loop Resistance    

  American Wire Gauge (AWG)         ohms/1000 ft       ohms/km

  19                                16.1               52.8

  22                                32.4               106.3

  24                                51.9               170.3

  26                                83.3               273.3
  --------------------------------- ------------------ ------------------

**3.4.6.2.2** Add the individual resistances for each gauge to give the
total calculated dc loop resistance at a temperature of 68°F (20°C).

**3.4.6.2.3** Correct the total calculated dc loop resistance at the
temperature of 68°F (20°C) to the measurement temperature by the
following formulae:

R~t~ = R~68~ x \[1 + 0.0022 x (t - 68)\] for English Units

R~t~ = R~20~ x \[1 + 0.0040 x (t - 20)\] for Metric Units

Where:

R~t~ = Loop resistance at the measurement temperature

in ohms.

R~68~ = Loop resistance at a temperature of 68°F

in ohms.

R~20~ = Loop resistance at a temperature of 20°C

in ohms.

t = Measurement temperature in °F or (°C).

**3.4.6.2.4** Compare the calculated dc loop resistance at the
measurement temperature to the measured dc loop resistance to determine
compliance with the requirement specified in Paragraph 3.4.6.1 of this
bulletin.

**3.4.6.3** Resistance varies directly with temperature change. For
copper conductor cables, the dc resistance changes by ± 1% for every ±
5°F (2.8°C) change in temperature from 68°F (20°C).

**3.4.6.4** The dc resistance unbalance between the individual
conductors of a pair shall not exceed that value which will result in a
circuit balance of less than 60 dB when computed from noise measurements
as described in Paragraph 3.5 of this bulletin. It is impractical to
establish a precise limit for overall circuit dc resistance unbalance
due to the factors controlling its contribution to circuit noise. These
factors include location of the resistance unbalance in relation to a
low impedance path to ground (close to the central office) and the
magnitude of unbalance in short lengths of cable making up the total
circuit length. The objective is to obtain the minimum unbalance
throughout the entire circuit when it is ascertained through noise
measurements that dc resistance unbalance may be contributing to poor
cable balance.

**3.4.6.5** Pairs with poor noise balance may be improved by reversing
tip and ring conductors of pairs at cable splices. Where dc resistance
unbalances are systematic over the total trunk circuit or loop circuit
length, tip and ring reversals may be made at frequent intervals. Where
the unbalances are concentrated in a shorter section of cable, only one
tip and ring reversal should be required. Concentrated dc resistance
unbalance produces maximum circuit noise when located adjacent to the
central office. Concentrated dc resistance unbalance will contribute to
overall circuit noise at a point approximately two-thirds (2/3) of the
distance to the subscriber. All deliberate tip and ring reversals shall
be tagged and identified to prevent plant personnel from removing the
reversals when resplicing these connections in the future. The number of
tip and ring reversals shall be held to a minimum.

**3.4.6.6** A systematic dc resistance unbalance can sometimes be
accompanied by other cable parameters that are marginal. Among these are
pair-to-pair capacitance unbalance, capacitance unbalance-to-ground, and
150 kilohertz (kHz) crosstalk loss. Engineering judgment has to be
applied in each case. Rejection of cable for excessive dc resistance
unbalance shall only apply to a single reel length, or shorter.

**3.4.7 [Data Record]{.underline}:** The measurement data for dc loop
resistance and dc resistance unbalance shall be recorded. Suggested
formats similar to Format I for subscriber loops and Format II for trunk
circuits in Paragraph 7 of this bulletin or formats specified in the
applicable construction contract may be used.

**3.4.8 [Probable Causes for Nonconformance]{.underline}:** Dc loop
resistance and dc resistance unbalance are usually the result of the
resistance of individual conductors used in the manufacture of the
cable. Resistance unbalance can be worsened by defective splicing of the
conductors (splicing connectors, improper crimping tool, etc.).

**3.5 [Subscriber Loop Measurement (Loop Checking)]{.underline}:**

**3.5.1** When specified by the borrower, insertion loss and noise
measurements shall be performed on subscriber loops after connection of
a line circuit to the loop by the one person method using loop checking
equipment from the customer access location. For this method, the
central office should be equipped with a 900 ohm plus two microfarad
quiet termination and a milliwatt generator having the required test
frequencies; or a portable milliwatt generator having the desired
frequencies may be used, especially, where several small offices are
involved.

**3.5.2** At a minimum, insertion loss and frequency response of
subscriber loop plant shall be measured at 1,000, 1,700, 2,300, and
2,800 Hertz (Hz). When additional testing frequencies are desired, the
additional frequencies shall be specified in the applicable construction
contract.

**3.5.3** Measurements of insertion loss and noise shall be made on five
percent or more of the pairs. A minimum of five pairs shall be tested on
each route. Pairs shall be selected on a random basis with greater
consideration in the selection given to the longer loops. Consideration
shall be given to measuring a large percentage, up to 100 percent, of
all loops.

**3.5.4 [Method of Measurement]{.underline}:**

**3.5.4.1 [Insertion Loss]{.underline}:** The step-by-step measurement
procedure shall be as shown in Figure 6. The output level of the
milliwatt generator tones shall be determined prior to leaving the CO.
This shall be accomplished by dialing the milliwatt generator number
from a spare line at the MDF and measuring with the same equipment to be
used in the tests at customer access locations. The output levels shall
be recorded for reference later. Insertion loss measurements shall be
made across the tip and ring terminals of the pair under test.

**3.5.4.2 [Noise]{.underline}:** The step-by-step measurement procedure
shall be as shown in Figure 7. Prior to leaving the CO for testing, dial
the 900 ohm plus two microfarad quiet termination from a spare pair and
measure the termination to determine that it actually is quiet. Circuit
noise (noise-metallic) shall be measured at the customer access location
across the tip and ring terminals of the pair under test. Power
influence (direct reading with loop checking equipment) shall be
measured at the customer access location from tip and ring
conductors-to-ground(this connection is completed via the test unit).
The power influence measurement includes the entire talking connection
from the quiet termination to the customer. (That is, the power
influence measurement includes all the CO equipment which normally makes
up the connection.)

**3.5.5 [Test Equipment]{.underline}:**

**3.5.5.1** Loop checking equipment which is available from several
manufacturers may be used for these measurements. The equipment should
have the capability of measuring loop current, insertion loss, circuit
noise (NM) and power influence (PI). The test equipment manufacturer\'s
operating instructions shall be followed.

**3.5.5.2** There should be no measurable transmission loss when testing
through loop extenders.

**3.5.6 [Applicable Results]{.underline}:**

**3.5.6.1 [Insertion Loss]{.underline}:**

**3.5.6.1.1** For D66 loaded cables (a specific loading scheme using a
66 millihenry inductor spaced nominally at 4,500 ft \[1,371 m\]
intervals) measured at a point one-half section length beyond the last
load point, the measured nonrepeatered insertion loss shall be within ±
10% at 1000, 1700, 2300, and 2800 Hz, ± 15% at 3400 Hz and ± 20% at 4000
Hz of the calculated insertion loss at the same frequencies and
temperature.

**3.5.6.1.2** For H88 loaded cables (a specific loading scheme using an
88 millihenry inductor spaced nominally at 6,000 ft \[1,829 m\]
intervals) measured at a point one-half section length beyond the last
load point, the measured nonrepeatered insertion loss shall be within ±
10% at 1000, 1700, and 2300 Hz, ± 15% at 2800 Hz, and ± 20% at 3400 Hz
of the calculated insertion loss at the same frequencies and
temperature.

**3.5.6.1.3** For nonloaded cables, the measured insertion loss shall be
within ± 10% at 1000, 1700, 2300, and 2800 Hz, ± 15% at

3400 Hz and ± 20% at 4000 Hz of the calculated insertion loss at the
same frequencies and temperature.

**3.5.6.1.4** For loaded cables, the calculated loss at each desired
frequency shall be computed as follows:

a\. Multiply the length in miles (km) of each different

gauge in the loaded portion of the loop (between the

office and a point one-half load section beyond the

furthest load point) by the applicable decibel (dB)/mile

(dB/km) value shown in Table 4 or 5. This loss

represents the total loss for each gauge in the loaded

portion of the loop;

b\. Multiply the length in miles (km) of each different

gauge in the end section or nonloaded portion of the

cable (beyond a point one-half load section beyond the

furthest load point) by the applicable dB/mile (dB/km)

value shown in Table 6. This loss represents the total

loss for each gauge in the nonloaded portion of the

loop; and

c\. The total calculated insertion loss is computed by

adding the individual losses determined in Items (a)

and (b) of Paragraph 3.5.6.1.4 of this bulletin.

**3.5.6.1.5** For nonloaded cables, the calculated loss at each desired
frequency shall be computed by multiplying the length in miles (km) of
each different gauge by the applicable dB/mile (dB/km) value shown in
Table 6 and then adding the individual losses for each gauge to
determine the total calculated insertion loss for the nonloaded loop.

**3.5.6.1.6** The attenuation information in Tables 4, 5, and 6 are
based on a cable temperature of 68°F (20°C). Insertion loss varies
directly with temperature. To convert measured losses for loaded cables
to a different temperature, use the following value for copper
conductors: For each ± 5°F (± 2.8°C) change in the temperature from 68°F
(20°C), change the insertion loss at any frequency by ± 1%. To convert
measured losses for nonloaded cables to a different temperature, use the
following value for copper conductors: For each ± 10°F (± 5.6°C) change
in the temperature from 68°F (20°C), change the insertion loss at any
frequency by ± 1%. Tables 4, 5, and 6 are as follows:

+------------+-------------+-------------+-------------+-------------+
| Table 4 -  |             |             |             |             |
| Frequency  |             |             |             |             |
| A          |             |             |             |             |
| ttenuation |             |             |             |             |
| @ 68°F     |             |             |             |             |
| (20°C)     |             |             |             |             |
|            |             |             |             |             |
| D66 Loaded |             |             |             |             |
| Exchange   |             |             |             |             |
| Cables     |             |             |             |             |
|            |             |             |             |             |
| 83         |             |             |             |             |
| nanofarad  |             |             |             |             |
| (nF)/mile  |             |             |             |             |
| (52 nF/km) |             |             |             |             |
| (See Note) |             |             |             |             |
+------------+-------------+-------------+-------------+-------------+
| Frequency  | Attenuation |             |             |             |
|            | dB/mile     |             |             |             |
|            | (dB/km)     |             |             |             |
|            |             |             |             |             |
|            | AWG         |             |             |             |
+------------+-------------+-------------+-------------+-------------+
| (Hz)       | 19          | 22          | 24          | 26          |
+------------+-------------+-------------+-------------+-------------+
| 200        | 0.41 (0.26) | 0.67 (0.42) | 0.90 (0.56) | 1.21 (0.75) |
+------------+-------------+-------------+-------------+-------------+
| 400        | 0.43 (0.26) | 0.77 (0.48) | 1.09 (0.68) | 1.53 (0.95) |
+------------+-------------+-------------+-------------+-------------+
| 600        | 0.44 (0.27) | 0.80 (0.49) | 1.17 (0.73) | 1.70 (1.06) |
+------------+-------------+-------------+-------------+-------------+
| 800        | 0.44 (0.27) | 0.81 (0.50) | 1.21 (0.75) | 1.80 (1.12) |
+------------+-------------+-------------+-------------+-------------+
| 1000       | 0.44 (0.27) | 0.82 (0.51) | 1.23 (0.76) | 1.86 (1.15) |
+------------+-------------+-------------+-------------+-------------+
| 1200       | 0.45 (0.28) | 0.83 (0.52) | 1.24 (0.77) | 1.91 (1.19) |
+------------+-------------+-------------+-------------+-------------+
| 1400       | 0.45 (0.28) | 0.83 (0.52) | 1.26 (0.78) | 1.94 (1.20) |
+------------+-------------+-------------+-------------+-------------+
| 1600       | 0.45 (0.28) | 0.84 (0.52) | 1.26 (0.78) | 1.96 (1.22) |
+------------+-------------+-------------+-------------+-------------+
| 1800       | 0.45 (0.28) | 0.84 (0.52) | 1.27 (0.78) | 1.98 (1.23) |
+------------+-------------+-------------+-------------+-------------+
| 2000       | 0.46 (0.29) | 0.85 (0.53) | 1.28 (0.79) | 1.99 (1.24) |
+------------+-------------+-------------+-------------+-------------+
| 2200       | 0.46 (0.29) | 0.85 (0.53) | 1.29 (0.80) | 2.01 (1.25) |
+------------+-------------+-------------+-------------+-------------+
| 2400       | 0.47 (0.29) | 0.86 (0.53) | 1.30 (0.81) | 2.02 (1.26) |
+------------+-------------+-------------+-------------+-------------+
| 2600       | 0.47 (0.29) | 0.87 (0.54) | 1.31 (0.81) | 2.04 (1.27) |
+------------+-------------+-------------+-------------+-------------+
| 2800       | 0.48 (0.30) | 0.88 (0.55) | 1.32 (0.82) | 2.07 (1.29) |
+------------+-------------+-------------+-------------+-------------+
| 3000       | 0.49 (0.30) | 0.89 (0.55) | 1.34 (0.83) | 2.10 (1.30) |
+------------+-------------+-------------+-------------+-------------+
| 3200       | 0.50 (0.31) | 0.91 (0.57) | 1.36 (0.84) | 2.13 (1.32) |
+------------+-------------+-------------+-------------+-------------+
| 3400       | 0.52 (0.32) | 0.93 (0.58) | 1.40 (0.87) | 2.19 (1.36) |
+------------+-------------+-------------+-------------+-------------+
| 3600       | 0.54 (0.34) | 0.97 (0.60) | 1.45 (0.90) | 2.26 (1.40) |
+------------+-------------+-------------+-------------+-------------+
| 3800       | 0.57 (0.35) | 1.02 (0.63) | 1.52 (0.94) | 2.36 (1.47) |
+------------+-------------+-------------+-------------+-------------+
| 4000       | 0.62 (0.38) | 1.10 (0.68) | 1.63 (1.01) | 2.53 (1.57) |
+------------+-------------+-------------+-------------+-------------+

Note: Between end-section lengths of 2,250 ft (686 m) for D66 loading.

+------------+-------------+-------------+-------------+--------------+
| Table 5 -  |             |             |             |              |
| Frequency  |             |             |             |              |
| A          |             |             |             |              |
| ttenuation |             |             |             |              |
| @ 68°F     |             |             |             |              |
| (20°C)     |             |             |             |              |
|            |             |             |             |              |
| H88 Loaded |             |             |             |              |
| Exchange   |             |             |             |              |
| Cables     |             |             |             |              |
|            |             |             |             |              |
| 83 nF/mile |             |             |             |              |
| (52 nF/km) |             |             |             |              |
| (See Note) |             |             |             |              |
+------------+-------------+-------------+-------------+--------------+
| Frequency  | Attenuation |             |             |              |
|            | dB/mile     |             |             |              |
|            | (dB/km)     |             |             |              |
|            |             |             |             |              |
|            | AWG         |             |             |              |
+------------+-------------+-------------+-------------+--------------+
| (Hz)       | 19          | 22          | 24          | 26           |
+------------+-------------+-------------+-------------+--------------+
| 200        | 0.40 (0.25) | 0.66 (0.41) | 0.90 (0.56) | 1.20 (0.75)  |
+------------+-------------+-------------+-------------+--------------+
| 400        | 0.42 (0.26) | 0.76 (0.47) | 1.08 (0.67) | 1.53 (0.95)  |
+------------+-------------+-------------+-------------+--------------+
| 600        | 0.43 (0.27) | 0.79 (0.49) | 1.16 (0.72) | 1.70 (1.06)  |
+------------+-------------+-------------+-------------+--------------+
| 800        | 0.43 (0.27) | 0.80 (0.50) | 1.20 (0.75) | 1.80 (1.12)  |
+------------+-------------+-------------+-------------+--------------+
| 1000       | 0.43 (0.27) | 0.81 (0.50) | 1.23 (0.76) | 1.86 (1.15)  |
+------------+-------------+-------------+-------------+--------------+
| 1200       | 0.44 (0.27) | 0.82 (0.51) | 1.24 (0.77) | 1.91 (1.19)  |
+------------+-------------+-------------+-------------+--------------+
| 1400       | 0.44 (0.28) | 0.82 (0.51) | 1.25 (0.78) | 1.94 (1.20)  |
+------------+-------------+-------------+-------------+--------------+
| 1600       | 0.44 (0.27) | 0.83 (0.52) | 1.26 (0.78) | 1.97 (1.22)  |
+------------+-------------+-------------+-------------+--------------+
| 1800       | 0.45 (0.28) | 0.84 (0.52) | 1.28 (0.79) | 1.99 (1.24)  |
+------------+-------------+-------------+-------------+--------------+
| 2000       | 0.46 (0.29) | 0.85 (0.53) | 1.29 (0.80) | 2.02 (1.26)  |
+------------+-------------+-------------+-------------+--------------+
| 2200       | 0.47 (0.29) | 0.86 (0.53) | 1.31 (0.81) | 2.06 (1.28)  |
+------------+-------------+-------------+-------------+--------------+
| 2400       | 0.48 (0.30) | 0.89 (0.55) | 1.34 (0.83) | 2.10 (1.30)  |
+------------+-------------+-------------+-------------+--------------+
| 2600       | 0.50 (0.31) | 0.92 (0.57) | 1.39 (0.86) | 2.18 (1.35)  |
+------------+-------------+-------------+-------------+--------------+
| 2800       | 0.53 (0.33) | 0.97 (0.60) | 1.47 (0.91) | 2.29 (1.42)  |
+------------+-------------+-------------+-------------+--------------+
| 3000       | 0.59 (0.37) | 1.07 (0.66) | 1.60 (0.99) | 2.48 (1.54)  |
+------------+-------------+-------------+-------------+--------------+
| 3200       | 0.71 (0.44) | 1.26 (0.78) | 1.87 (1.16) | 2.86 (1.78)  |
+------------+-------------+-------------+-------------+--------------+
| 3400       | 1.14 (0.71) | 1.91 (1.19) | 2.64 (1.64) | 3.71 (2.30)  |
+------------+-------------+-------------+-------------+--------------+
| 3600       | 4.07 (2.53) | 4.31 (2.68) | 4.65 (2.90) | 5.30 (3.29)  |
+------------+-------------+-------------+-------------+--------------+
| 3800       | 6.49 (4.03) | 6.57 (4.08) | 6.72 (4.18) | 7.06 (4.39)  |
+------------+-------------+-------------+-------------+--------------+
| 4000       | 8.22 (5.11) | 8.27 (5.14) | 8.36 (5.19) | 8.58 (5.33)  |
+------------+-------------+-------------+-------------+--------------+

Note: Between end-section lengths of 3,000 ft (914 m) for H88 loading.

+------------+--------------+------------+-------------+--------------+
| Table 6 -  |              |            |             |              |
| Frequency  |              |            |             |              |
| A          |              |            |             |              |
| ttenuation |              |            |             |              |
| @ 68°F     |              |            |             |              |
| (20°C)     |              |            |             |              |
|            |              |            |             |              |
| Nonloaded  |              |            |             |              |
| Exchange   |              |            |             |              |
| Cables     |              |            |             |              |
|            |              |            |             |              |
| 83 nF/mile |              |            |             |              |
| (52 nF/km) |              |            |             |              |
+------------+--------------+------------+-------------+--------------+
| Frequency  | Attenuation  |            |             |              |
|            | dB/mile      |            |             |              |
|            | (dB/km)      |            |             |              |
|            |              |            |             |              |
|            | AWG          |            |             |              |
+------------+--------------+------------+-------------+--------------+
| (Hz)       | 19           | 22         | 24          | 26           |
+------------+--------------+------------+-------------+--------------+
| 200        | 0.58 (0.36)  | 0.82       | 1.03 (0.64) | 1.30 (0.81)  |
|            |              | (0.51)     |             |              |
+------------+--------------+------------+-------------+--------------+
| 400        | 0.81 (0.51)  | 1.15       | 1.45 (0.90) | 1.84 (1.14)  |
|            |              | (0.71)     |             |              |
+------------+--------------+------------+-------------+--------------+
| 600        | 0.98 (0.61)  | 1.41       | 1.77 (1.10) | 2.26 (1.40)  |
|            |              | (0.87)     |             |              |
+------------+--------------+------------+-------------+--------------+
| 800        | 1.13 (0.70)  | 1.62       | 2.04 (1.27) | 2.60 (1.61)  |
|            |              | (1.01)     |             |              |
+------------+--------------+------------+-------------+--------------+
| 1000       | 1.25 (0.78)  | 1.80       | 2.28 (1.42) | 2.90 (1.80)  |
|            |              | (1.12)     |             |              |
+------------+--------------+------------+-------------+--------------+
| 1200       | 1.36 (0.84)  | 1.97       | 2.50 (1.55) | 3.17 (1.97)  |
|            |              | (1.22)     |             |              |
+------------+--------------+------------+-------------+--------------+
| 1400       | 1.46 (0.91)  | 2.12       | 2.69 (1.67) | 3.42 (2.12)  |
|            |              | (1.32)     |             |              |
+------------+--------------+------------+-------------+--------------+
| 1600       | 1.55 (0.96)  | 2.26       | 2.87 (1.78) | 3.65 (2.27)  |
|            |              | (1.40)     |             |              |
+------------+--------------+------------+-------------+--------------+
| 1800       | 1.63 (1.01)  | 2.39       | 3.04 (1.89) | 3.87 (2.40)  |
|            |              | (1.48)     |             |              |
+------------+--------------+------------+-------------+--------------+
| 2000       | 1.71 (1.06)  | 2.51       | 3.20 (1.99) | 4.08 (2.53)  |
|            |              | (1.56)     |             |              |
+------------+--------------+------------+-------------+--------------+
| 2200       | 1.78 (1.11)  | 2.62       | 3.35 (2.08) | 4.27 (2.65)  |
|            |              | (1.63)     |             |              |
+------------+--------------+------------+-------------+--------------+
| 2400       | 1.85 (1.15)  | 2.73       | 3.49 (2.17) | 4.45 (2.76)  |
|            |              | (1.70)     |             |              |
+------------+--------------+------------+-------------+--------------+
| 2600       | 1.91 (1.19)  | 2.83       | 3.62 (2.25) | 4.63 (2.88)  |
|            |              | (1.76)     |             |              |
+------------+--------------+------------+-------------+--------------+
| 2800       | 1.97 (1.22)  | 2.93       | 3.75 (2.33) | 4.80 (2.98)  |
|            |              | (1.82)     |             |              |
+------------+--------------+------------+-------------+--------------+
| 3000       | 2.03 (1.26)  | 3.02       | 3.88 (2.41) | 4.96 (3.08)  |
|            |              | (1.88)     |             |              |
+------------+--------------+------------+-------------+--------------+
| 3200       | 2.08 (1.29)  | 3.11       | 4.00 (2.48) | 5.12 (3.18)  |
|            |              | (1.93)     |             |              |
+------------+--------------+------------+-------------+--------------+
| 3400       | 2.13 (1.32)  | 3.19       | 4.11 (2.55) | 5.27 (3.27)  |
|            |              | (1.98)     |             |              |
+------------+--------------+------------+-------------+--------------+
| 3600       | 2.18 (1.35)  | 3.28       | 4.22 (2.62) | 5.41 (3.36)  |
|            |              | (2.04)     |             |              |
+------------+--------------+------------+-------------+--------------+
| 3800       | 2.22 (1.38)  | 3.36       | 4.33 (2.69) | 5.55 (3.45)  |
|            |              | (2.09)     |             |              |
+------------+--------------+------------+-------------+--------------+
| 4000       | 2.27 (1.41)  | 3.43       | 4.43 (2.75) | 5.69 (3.53)  |
|            |              | (2.13)     |             |              |
+------------+--------------+------------+-------------+--------------+

**3.5.6.1.7** For loaded subscriber loops, the 1 kHz loss shall be
approximately 0.45 dB per 100 ohms of measured dc loop resistance. This
loss shall be the measured loss less the net gain of any voice frequency
repeaters in the circuit. Testing shall also be conducted to verify that
the loss increases gradually as the frequency increases. The loss on H88
loaded loops should be down only slightly at 2.8 kHz but drop rapidly
above 2.8 kHz. The loss on D66 loaded loops shall be fairly constant to
about 3.4 kHz and there shall be good response at 4.0 kHz. When voice
frequency repeaters are in the circuit there will be some frequency
weighting in the build-out network and the loss at the higher
frequencies will be greater than for nonrepeatered loops.

**3.5.6.1.8** For nonloaded subscriber loops, the 1 kHz loss shall be
approximately 0.9 dB per 100 ohms of measured dc loop resistance.
Testing shall also be conducted to verify that the loss is approximately
a straight line function with no abrupt changes. The 3 kHz loss should
be approximately 70% higher than the 1 kHz loss.

**3.5.6.2 [Noise]{.underline}:** The principal objective related to
circuit noise (noise-metallic) and the acceptance of new plant is that
circuit noise levels be 20 dBrnc or less \[decibels above reference
noise, C-message weighted (a weighting derived from listening tests, to
indicate the relative annoyance or speech impairment by an interfering
signal of frequency (f) as heard through a \"500-type\" telephone
set)\]. For most new, properly installed, plant construction, circuit
noise will usually be considerably less than 20 dBrnc unless there are
unusually long sections of telephone plant in parallel with electric
power facilities and/or power influence of paralleling electric
facilities is abnormally high. When circuit noise is 20 dBrnc or less,
the loop plant shall be considered acceptable. When measured circuit
noise is greater than 20 dBrnc, loop plant shall still be considered
acceptable providing circuit balance (power influence reading minus
circuit noise readings) is 60 dB or greater and power influence readings
are 85 dBrnc or greater. When circuit noise is greater than 20 dBrnc and
circuit balance is less than 60 dB and/or power influence is less than
85 dBrnc, loop plant shall not be considered acceptable and the loop
plant shall be remedied to make circuit balance equal to or greater than
60 dB.

**3.5.7 [Data Record]{.underline}:** Measurement data shall be recorded.
A suggested format similar to Format I for subscriber loops in Paragraph
7 of this bulletin or a format specified in the applicable construction
contract may be used.

**3.5.8 [Probable Causes for Nonconformance]{.underline}:**

**3.5.8.1 [Insertion Loss]{.underline}:** Some of the more common causes
for failing to obtain the desired results may be due to reversed load
coil windings, missing load coils, bridge taps between load coils, load
coil spacing irregularities, excessive end sections, cables having high
or low mutual capacitance, load coils having the wrong inductance, load
coils inadvertently installed in nonloaded loops, moisture or water in
cable, split pairs, and improperly spliced connections. The above
factors can occur singularly or in combination. Experience to date
indicates that the most common problems are missing load coils, reversed
load coil windings or bridge taps.

**3.5.8.2 [Noise]{.underline}:** Some of the common causes for failing
to obtain the desired results may be due to high power influence from
paralleling electrical power systems, poor telephone circuit balance,
discontinuous cable shields, inadequate bonding and grounding of cable
shields, high capacitance unbalance-to-ground of the cable pairs, high
dc loop resistance unbalance, dc loop current less than 20 milliamperes,
etc. The above factors can occur singularly or in combination. See TE&CM
Section 451, Telephone Noise Measurement and Mitigation, for steps to be
taken in reducing telecommunications line noise.

**3.6 [One-Person Open Circuit Measurement (Subscriber
Loops)]{.underline}:**

**3.6.1** When specified by the borrower, open circuit measurements
shall be made on all loaded and nonloaded subscriber loops upon
completion of the cable work to verify that the plant is free from major
impedance irregularities.

**3.6.2** For loaded loops, open circuit measurements shall be made
using one of the following methods:

a\. Impedance or pulse return pattern, with cable pair trace

compared to that of an artificial line of the same

length and gauge. For best results, a level tracer or

fault locator with dual trace capability is required;

b\. Return loss using a level tracer, with cable pair

compared to an artificial line of the same length and

gauge connected in lieu of a Precision Balance Network

(PBN). This method can be made with level tracers

having only single trace capability; or

c\. Open circuit structural return loss using a level

tracer. This method can be made with level tracer

having only single trace capability.

**3.6.3** Of the three methods suggested for loaded loops, the method
specified in item (b.) of Paragraph 3.6.2 of this bulletin is the
preferred method because it can yield both qualitative and quantitative
results. The methods specified in items (a.) and (c.) of Paragraph 3.6.2
of this bulletin can be used as trouble shooting tools should
irregularities be found during testing.

**3.6.4** For nonloaded loops, open circuit measurements shall be made
using the method specified in item (a.)of Paragraph 3.6.2 of this
bulletin.

**3.6.5 [Method of Measurement]{.underline}:** Open circuit measurements
shall be made at the CO on each loaded and nonloaded pair across the tip
and ring terminals of the pair under test. All CO equipment shall be
disconnected at the MDF for this test. For loaded loops containing voice
frequency repeaters installed in the CO or field mounted, the open
circuit measurement shall be made after the repeaters have been
disconnected. Where field mounted repeaters are used, the open circuit
measurement shall be made at the repeater location in both directions.

**3.6.5.1 [Impedance or Pulse Return Pattern]{.underline}:** The
step-by-step measurement procedure using the impedance or pulse return
pattern for loaded and nonloaded loops shall be as shown in Figure 8. An
artificial line of the same makeup as the cable to be tested shall be
set up. The traces of the impedance or pulse return pattern from the
cable pair and the artificial line shall be compared and should be
essentially identical. If the impedance or pulse return traces from the
cable pair are different than the artificial line trace, cable faults
are possible. When the cable pair trace indicates possible defects, the
defects should be identified and located. One method of identifying and
locating defects involves introducing faults into the artificial line
until its trace is identical with the cable trace.

**3.6.5.2 [Return Loss Balanced to Artificial Line]{.underline}:** The
step-by-step measurement procedure using the return loss balanced to
artificial line for loaded loops shall be as shown in Figure 9. An
artificial line of the same makeup as the cable to be tested shall be
set up. The artificial line is connected to the external network
terminals of the test set. The cable pair under test is compared to this
standard. When defects are found, they should be identified and located
by introducing faults into the artificial line. This is more difficult
than with the method referenced in Paragraph 3.6.5.1 of this bulletin
since this measurement is more sensitive to minor faults and only a
single trace is used.

**3.6.5.3 [Open Circuit Structural Return Loss using Level
Tracer]{.underline}:** The step-by-step measurement procedure using the
level tracer for loaded loops shall be as shown in Figure 10. The cable
pair is compared to a PBN.

**3.6.6 [Test Equipment]{.underline}:** Equipment for performing these
tests is shown in Figures 8 through 10. For loaded loops, artificial
loaded lines must be of the same gauge and loading scheme as the line
under test. For nonloaded loops, artificial nonloaded lines must be of
the same gauge as the line under test. Artificial lines should be
arranged using switches or other quick connect arrangements to speed
testing and troubleshooting.

**3.6.7 [Applicable Results]{.underline}:**

**3.6.7.1** For loaded and nonloaded loops, the two traces in the pulse
return pattern or impedance method (Paragraph 3.6.5.1 of this bulletin)
shall be essentially identical. The degree of comparison required of the
two traces is to be determined by experience.

**3.6.7.2** For loaded loops, results for return loss measurements using
a level tracer, with artificial line, in lieu of a PBN (Paragraph
3.6.5.2 of this bulletin) shall meet the following requirements:

a\. For D66 and H88 loaded cables the structural return

loss (SRL) values shall range between 28 and 39 dB,

respectively, at the critical frequency of structural

return loss (CFSRL) within the pass band of the loading

system being used. The minimum SRL value for uniform

gauge shall be 25 dB CFSRL. These SRL values apply for

loaded cables of uniform gauge for the entire length of

the subscriber loop circuit. Subscriber loop circuits

shall meet the loading spacing deviations and the cable

mutual capacitance requirements in the applicable RUS

cable specifications;

b\. For mixed gauge loaded cables the SRL values shall be

25 and 27 dB CFSRL, respectively, and the minimum SRL

value shall be 22 dB CFSRL; and

c\. The two traces in the pulse return pattern should be

essentially identical. The degree of comparison

required of the two traces is determined by experience.

**3.6.7.3** For loaded loops, the results of open circuit structural
return loss measurements using a level tracer (Paragraph 3.5.5.3 of this
bulletin) shall meet the following requirements. For D66 and H88 loaded
cables with uniform or mixed gauges, the worst value allowed for
measured open circuit structural return loss between 1,000 - 3,500 Hz
and 1,000 - 3,000 Hz, respectively, shall be approximately 0.9 dB (round
trip) for each 100 ohms outside plant dc loop resistance including the
resistance of the load coils. The value of 0.9 dB per 100 ohms for the
round trip loss remains reasonably accurate as long as:

a\. The subscriber end section of the loaded pair under

test is approximately 2,250 ft (685 m) for D66 loading

or 3,000 ft (914 m) for H88 loading in length; and

b\. The one-way 1,000 Hz loss does not exceed 10 dB.

**3.6.7.4** For loaded loops, the measured value of open circuit
structural return loss can only be as accurate as the degree to which
the dc loop resistance of the loaded pair under test is known. Most
accurate results shall be obtained when the dc loop resistance is known
by actual measurements as described in Paragraph 3.4 of this bulletin.
Furthermore, where the dc loop resistance is measured at the same time
as the open circuit structural return loss, no correction for
temperature is needed because the loss is directly proportional to the
loop resistance. Where it is not practical to measure the dc loop
resistance, it shall be calculated and corrected for temperature as
specified in Paragraph 3.4.6.2 of this bulletin. When measuring existing
plant, care shall be taken to verify the accuracy of the records, if
they are used for the calculation of the dc loop resistance. For buried
plant, the temperature correction shall be based at the normal depth of
the cable in the ground. (Temperature can be measured by boring a hole
to cable depth with a ground rod, placing a thermometer in the ground at
the cable depth, and taking and averaging several readings during the
course of the resistance measurements.) For aerial cable it shall be
based on the temperature inside the cable sheath.

**3.6.7.5** For loaded loops, the best correlation between the measured
and the expected results shall be obtained when the cable is of one
gauge, one size, and the far end section is approximately 2,250 ft (685
m) for D66 loading or 3,000 ft

(914 m) for H88 loading. Mixing gauges and cable sizes will result in
undesirable small reflections whose frequency characteristics and
magnitude cannot be accurately predicted. In subscriber loop
applications, cable gauge may be somewhat uniform but the cable pair
size most likely will not be uniform as cable pair sizes taper off
toward the customer access location and a downward adjustment of 1 dB of
the allowed value shall be acceptable. \"Long\" end sections (as defined
in TE&CM Section 424, \"Guideline for Telecommunications Subscriber Loop
Plant\") lower the expected value, a further downward adjustment of 3 dB
in the allowed value shall be acceptable.

**3.6.7.6** For loaded loops, the limiting factor when making open
circuit structural return loss measurements is when the 1,000 Hz one-way
loss of the loaded cable pair under test becomes 10 dB or greater; it
becomes difficult to detect the presence of irregularities beyond the 10
dB point on the loop. To overcome this difficulty, loaded loops having a
one-way loss at 1,000 Hz greater than 10 dB shall be opened at some
convenient point (such as a pedestal or ready access enclosure) and loss
measurements at the individual portions measuring less than 10 dB
one-way shall be made separately. When field mounted voice frequency
repeaters are used, the measurement shall be made at the repeater
location in both directions.

**3.6.8 [Data Record]{.underline}:**

**3.6.8.1** When performing a pulse return pattern or impedance open
circuit measurement on loaded and nonloaded loops, a \"check mark\"
indicating that the pair tests good or an \"X\" indicating that the pair
does not test good shall be recorded in the SRL column. A suggested
format similar to Format I for subscriber loops in Paragraph 7 of this
bulletin or a format specified in the applicable construction contract
may be used.

**3.6.8.2** When performing open circuit return loss measurements using
the return loss balanced to an artificial line or return loss using a
level tracer on loaded loops, the value of the poorest (lowest numerical
value) SRL and its frequency in the proper column between 1,000 and
3,500 Hz for D66 loading or between 1,000 and 3,000 Hz for H88 loading
shall be recorded. A suggested format similar to Format I for subscriber
loops in Paragraph 7 of this bulletin or a format specified in the
applicable construction contract may be used.

**3.6.9 [Probable Causes for Nonconformance]{.underline}:** Some of the
more common causes for failing to obtain the desired results may be due
to reversed load coil windings, missing load coils, bridge taps between
load coils, load coil spacing irregularities, excessive end sections,
cables having high or low mutual capacitance, load coils inadvertently
installed in nonloaded loops, moisture or water in the cable, load coils
having the wrong inductance, split pairs, and improperly spliced
connectors. The above can occur singularly or in combination. Experience
to date indicates that the most common problems are missing load coils,
reversed load coil windings or bridge taps.

**3.7 [Cable Insertion Loss Measurement (Carrier
Frequencies)]{.underline}:**

**3.7.1** When specified by the borrower, carrier frequency insertion
loss measurements shall be made on cable pairs used for T1, T1C, and/or
station carrier systems. Carrier frequency insertion loss shall be made
on a minimum of three pairs. Select at least one pair near the outside
of the core unit layup. If the three measured pairs are within 10% of
the calculated loss in dB corrected for temperature, no further testing
is necessary. If any of the measured pairs of a section are not within
10% of the calculated loss in dB, all pairs in that section used for
carrier transmission shall be measured.

**3.7.2 [Method of Measurement]{.underline}:** The step-by-step method
of measurement shall be as shown in Figure 11.

**3.7.3 [Test Equipment:]{.underline}** The test equipment is shown in
Figure 11.

**3.7.4 [Applicable Results]{.underline}:**

**3.7.4.1** The highest frequency to be measured is determined by the
type of carrier system. For T1 type carrier, the highest frequency is
normally 772 kHz. For T1C type carrier, the highest frequency is
normally 1576 kHz. The highest frequency to be measured for station
carrier is 140 kHz.

**3.7.4.2** The measured insertion loss of the cable shall be within ±
10% of the calculated loss in dB when the loss is corrected for
temperature.

**3.7.4.3** The calculated insertion loss is computed as follows:

a\. Multiply the length of each different gauge by the

applicable dB per unit length as shown in Table 7 or 8:

+------------+-------------+-------------+-------------+-------------+
| Table 7 -  |             |             |             |             |
| Cable      |             |             |             |             |
| A          |             |             |             |             |
| ttenuation |             |             |             |             |
| @ 68°F     |             |             |             |             |
| (20°C)     |             |             |             |             |
|            |             |             |             |             |
| Filled     |             |             |             |             |
| Cables -   |             |             |             |             |
| Solid      |             |             |             |             |
| Insulation |             |             |             |             |
+------------+-------------+-------------+-------------+-------------+
| Frequency  | Attenuation |             |             |             |
|            | dB/mile     |             |             |             |
|            | (dB/km)     |             |             |             |
|            |             |             |             |             |
|            | Gauge (AWG) |             |             |             |
+------------+-------------+-------------+-------------+-------------+
| (kHz)      | 19          | 22          | 24          | 26          |
+------------+-------------+-------------+-------------+-------------+
| 10         | 2.8 (1.7)   | 4.8 (2.9)   | 6.4 (3.9)   | 8.5 (5.3)   |
+------------+-------------+-------------+-------------+-------------+
| 20         | 3.2 (2.0)   | 5.8 (3.6)   | 8.2 (5.1)   | 11.2 (6.9)  |
+------------+-------------+-------------+-------------+-------------+
| 40         | 3.6 (2.2)   | 6.5 (4.0)   | 9.6 (6.0)   | 13.9 (8.6)  |
+------------+-------------+-------------+-------------+-------------+
| 60         | 4.0 (2.5)   | 6.9 (4.2)   | 10.3 (6.4)  | 15.2 (9.4)  |
|            |             |             |             |             |
| 80         | 4.5 (2.8)   | 7.3 (4.5)   | 10.7 (6.6)  | 16.0 (9.9)  |
+------------+-------------+-------------+-------------+-------------+
| 100        | 4.9 (3.0)   | 7.7 (4.7)   | 11.1 (6.8)  | 16.5 (10.2) |
+------------+-------------+-------------+-------------+-------------+
| 112        | 5.2 (3.2)   | 8.0 (4.9)   | 11.3 (7.0)  | 16.8 (10.5) |
+------------+-------------+-------------+-------------+-------------+
| 120        | 5.4 (3.3)   | 8.1 (5.0)   | 11.5 (7.1)  | 17.0 (10.6) |
+------------+-------------+-------------+-------------+-------------+
| 140        | 5.8 (3.6)   | 8.6 (5.3)   | 11.9 (7.4)  | 17.4 (10.8) |
+------------+-------------+-------------+-------------+-------------+
| 160        | 6.2 (3.8)   | 9.0 (5.6)   | 12.3 (7.6)  | 17.8 (11.1) |
|            |             |             |             |             |
| 180        | 6.6 (4.1)   | 9.5 (5.9)   | 12.7 (7.9)  | 18.2 (11.3) |
+------------+-------------+-------------+-------------+-------------+
| 200        | 7.0 (4.3)   | 10.0 (6.2)  | 13.2 (8.2)  | 18.6 (11.5) |
+------------+-------------+-------------+-------------+-------------+
| 300        | 8.7 (5.4)   | 12.2 (7.5)  | 15.4 (9.6)  | 20.6 (12.8) |
+------------+-------------+-------------+-------------+-------------+
| 400        | 10.0 (6.2)  | 14.1 (8.8)  | 17.7 (11.0) | 22.9 (14.2) |
+------------+-------------+-------------+-------------+-------------+
| 500        | 11.2 (6.9)  | 15.9 (9.8)  | 19.8 (12.3) | 25.2 (15.6) |
+------------+-------------+-------------+-------------+-------------+
| 600        | 12.2 (7.5)  | 17.5 (10.9) | 21.8 (13.6) | 27.4 (17.0) |
|            |             |             |             |             |
| 700        | 13.2 (8.2)  | 19.0 (11.8) | 23.6 (14.7) | 29.6 (18.4) |
|            |             |             |             |             |
| 772        | 13.8 (8.5)  | 19.9 (12.4) | 24.8 (15.4) | 31.4 (19.5) |
|            |             |             |             |             |
| 800        | 14.2 (8.8)  | 20.1 (12.5) | 27.4 (17.1) | 31.7 (19.7) |
|            |             |             |             |             |
| 900        | 14.8 (9.2)  | 21.6 (13.4) | 29.0 (18.0) | 33.8 (21.0) |
+------------+-------------+-------------+-------------+-------------+
| 1000       | 15.8 (9.8)  | 22.7 (14.1) | 31.1 (19.3) | 35.9 (22.3) |
+------------+-------------+-------------+-------------+-------------+
| 1100       | 16.4 (10.2) | 23.8 (14.8) | 32.7 (20.3) | 38.0 (23.6) |
+------------+-------------+-------------+-------------+-------------+
| 1200       | 17.4 (10.8) | 24.8 (15.4) | 34.3 (21.3) | 40.0 (24.9) |
+------------+-------------+-------------+-------------+-------------+
| 1300       | 17.9 (11.1) | 25.9 (16.1) | 35.4 (22.0) | 41.7 (25.9) |
+------------+-------------+-------------+-------------+-------------+
| 1400       | 19.0 (11.8) | 26.9 (16.7) | 37.0 (23.0) | 43.3 (26.9) |
+------------+-------------+-------------+-------------+-------------+
| 1500       | 19.5 (12.1) | 28.0 (17.4) | 38.0 (23.6) | 44.3 (27.6) |
|            |             |             |             |             |
| 1576       | 20.1 (12.4) | 29.0 (18.0) | 39.0 (24.3) | 44.4 (28.2) |
+------------+-------------+-------------+-------------+-------------+

+------------+-------------+-------------+-------------+-------------+
| Table 8 -  |             |             |             |             |
| Cable      |             |             |             |             |
| A          |             |             |             |             |
| ttenuation |             |             |             |             |
| @ 68°F     |             |             |             |             |
| (20°C)     |             |             |             |             |
|            |             |             |             |             |
| Filled     |             |             |             |             |
| Cables -   |             |             |             |             |
| Expanded   |             |             |             |             |
| Insulation |             |             |             |             |
+------------+-------------+-------------+-------------+-------------+
| Frequency  | Attenuation |             |             |             |
|            | dB/mile     |             |             |             |
|            | (dB/km)     |             |             |             |
|            |             |             |             |             |
|            | Gauge (AWG) |             |             |             |
+------------+-------------+-------------+-------------+-------------+
| (kHz)      | 19          | 22          | 24          | 26          |
+------------+-------------+-------------+-------------+-------------+
| 10         | 3.0 (1.8)   | 4.9 (3.0)   | 6.5 (4.0)   | 8.6 (5.3)   |
+------------+-------------+-------------+-------------+-------------+
| 20         | 3.5 (2.1)   | 6.0 (4.1)   | 8.5 (5.2)   | 11.5 (7.1)  |
+------------+-------------+-------------+-------------+-------------+
| 40         | 4.0 (2.5)   | 7.0 (4.3)   | 10.2 (6.3)  | 14.4 (8.9)  |
+------------+-------------+-------------+-------------+-------------+
| 60         | 4.5 (2.8)   | 7.5 (4.6)   | 11.1 (6.8)  | 16.0 (9.9)  |
|            |             |             |             |             |
| 80         | 5.2 (3.3)   | 7.9 (4.9)   | 11.3 (6.9)  | 16.2 (10.1) |
+------------+-------------+-------------+-------------+-------------+
| 100        | 5.8 (3.6)   | 8.4 (5.2)   | 11.6 (7.2)  | 16.4 (10.2) |
+------------+-------------+-------------+-------------+-------------+
| 112        | 6.0 (3.8)   | 8.8 (5.4)   | 11.9 (7.4)  | 16.6 (10.3) |
+------------+-------------+-------------+-------------+-------------+
| 120        | 6.2 (3.9)   | 9.0 (5.6)   | 12.1 (7.5)  | 16.9 (10.5) |
+------------+-------------+-------------+-------------+-------------+
| 140        | 6.6 (4.1)   | 9.5 (5.9)   | 12.7 (7.9)  | 17.2 (10.7) |
+------------+-------------+-------------+-------------+-------------+
| 160        | 6.9 (4.3)   | 10.0 (6.2)  | 13.2 (8.2)  | 17.4 (10.8) |
|            |             |             |             |             |
| 180        | 7.4 (4.6)   | 10.6 (6.6)  | 13.7 (8.5)  | 17.9 (11.1) |
+------------+-------------+-------------+-------------+-------------+
| 200        | 7.9 (4.9)   | 11.1 (6.9)  | 14.2 (8.8)  | 18.5 (11.5) |
+------------+-------------+-------------+-------------+-------------+
| 300        | 9.5 (5.9)   | 13.2 (8.2)  | 16.8 (10.5) | 21.6 (13.4) |
+------------+-------------+-------------+-------------+-------------+
| 400        | 11.1 (6.9)  | 15.3 (9.5)  | 19.5 (12.1) | 24.3 (15.1) |
+------------+-------------+-------------+-------------+-------------+
| 500        | 12.1 (7.5)  | 17.9 (11.1) | 22.2 (13.8) | 27.4 (17.1) |
+------------+-------------+-------------+-------------+-------------+
| 600        | 13.7 (8.5)  | 19.5 (12.1) | 24.3 (15.1) | 29.6 (18.4) |
|            |             |             |             |             |
| 700        | 14.8 (9.2)  | 21.1 (13.1) | 26.4 (16.4) | 32.2 (20.0) |
|            |             |             |             |             |
| 772        | 15.3 (9.5)  | 21.6 (13.4) | 27.4 (17.1) | 33.8 (21.0) |
|            |             |             |             |             |
| 800        | 15.8 (9.8)  | 22.2 (13.8) | 28.0 (17.4) | 34.4 (21.3) |
|            |             |             |             |             |
| 900        | 17.0 (10.5) | 23.8 (14.8) | 29.6 (18.4) | 36.4 (22.6) |
+------------+-------------+-------------+-------------+-------------+
| 1000       | 17.4 (10.8) | 24.8 (15.4) | 31.1 (19.3) | 38.5 (23.9) |
+------------+-------------+-------------+-------------+-------------+
| 1100       | 17.9 (11.1) | 26.4 (16.4) | 33.3 (20.7) | 40.6 (25.3) |
+------------+-------------+-------------+-------------+-------------+
| 1200       | 19.0 (11.8) | 27.4 (17.1) | 34.3 (21.3) | 42.2 (26.2) |
+------------+-------------+-------------+-------------+-------------+
| 1300       | 19.5 (12.1) | 28.5 (17.7) | 35.9 (22.3) | 43.8 (27.2) |
+------------+-------------+-------------+-------------+-------------+
| 1400       | 20.1 (12.5) | 29.6 (18.4) | 37.0 (23.0) | 45.9 (28.5) |
+------------+-------------+-------------+-------------+-------------+
| 1500       | 20.6 (12.8) | 30.6 (19.0) | 38.5 (23.9) | 47.5 (29.5) |
|            |             |             |             |             |
| 1576       | 21.6 (13.4) | 31.1 (19.3) | 39.1 (24.3) | 48.6 (30.2) |
+------------+-------------+-------------+-------------+-------------+

b\. Add the individual losses for each gauge to give the

total calculated insertion loss at a temperature of

68°F (20°C);

c\. Correct the total calculated insertion loss at the

temperature of 68°F (20°C) to the measurement

temperature by the following formulae:

A~t~ = A~68~ x \[1 + 0.0012 x (t - 68)\] for English Units

A~t~ = A~20~ x \[1 + 0.0022 x (t - 20)\] for Metric Units

Where:

A~t~ = Insertion loss at the measurement temperature

in dB.

A~68~ = Insertion loss at a temperature of 68°F in dB.

A~20~ = Insertion loss at a temperature of 20°C in dB.

t = Measurement temperature in °F or (°C); and

d\. Compare the calculated insertion loss at the measurement

temperature to the measured insertion loss to determine

compliance with the requirement specified in Paragraph

3.7.4.2 of this bulletin. (Note: Attenuation varies

directly with temperature. For each ± 10°F (5.6°C)

change in temperature increase or decrease the

attenuation by ± 1%.)

**3.7.4.4** If the measured value exceeds the ± 10% allowable variation,
the cause shall be determined and corrective action shall be taken to
remedy the problem.

**3.7.5 [Data Record]{.underline}:** Results of carrier frequency
insertion loss measurements for station, T1, and/or T1C type carrier
shall be recorded. Suggested formats similar to Format III, Outside
Plant Acceptance Tests - T1 or T1C Carrier Pairs, and Format IV, Outside
Plant Acceptance Tests - Station Carrier Pairs, in Paragraph 7 of this
bulletin or formats specified in the applicable construction contract
may be used.

**3.7.6 [Probable Causes for Nonconformance]{.underline}:** If the
measured loss is low, the cable records are likely to be in error. If
the measured loss is high, there may be bridge taps, load coils or voice
frequency build-out capacitors connected to the cable pairs or the cable
records may be in error. Figures 12 and 13 are examples that show the
effects of bridge taps and load coils in the carrier path.

**4. FIBER OPTIC CABLE TELECOMMUNICATIONS PLANT MEASUREMENTS**

**4.1 [Armor Continuity]{.underline}:**

**4.1.1** Tests and measurements shall be made to ensure that the armor
of fiber optic cables is continuous. There are two areas of concern. The
first is armor bonding within a splice and the second is armor
continuity between splices.

**4.1.2** Measurement techniques outlined here for verification of armor
continuity are applicable to buried fiber optic cable plant.
Measurements of armor continuity between splices in aerial, armored,
fiber optic cable should be made prior to completion of splicing.
Conclusive results cannot be obtained on aerial plant after all bonds
have been completed to the supporting strand, multigrounded neutral,
etc.

**4.1.3 [Method of Measurement]{.underline}:** Armor continuity within
splices shall be measured with a cable shield splice continuity test
set. The step-by-step measurement procedure outlined in the
manufacturer\'s operating instructions for the specific test equipment
being used shall be followed.

**4.1.4 [Test Equipment]{.underline}:** A cable shield splice continuity
tester shall be used to measure armor continuity within splices.

**4.1.5 [Applicable Results]{.underline}:** When utilizing shield
continuity testers to measure armor continuity within splices, refer to
the manufacturer\'s published information covering the specific test
equipment to be used and for anticipated results.

**4.1.6 [Data Record]{.underline}:** Measurement data from armor
continuity tests shall be recorded together with anticipated values in
an appropriate format to permit comparison. The recorded data shall
include specific location, cable size, and cable type, if known, etc.

**4.1.7 [Probable Causes for Nonconformance]{.underline}:** Among
probable causes for nonconformance are broken or damaged armors, bad
bonding harnesses, poorly connected bonding clamps, loose bonding lugs,
etc.

**4.2 [Fiber Optic Splice Loss Measurement]{.underline}:**

**4.2.1** After placement of all fiber optic cable plant has been
completed and spliced together to form a continuous optical link between
end termination points, splice loss measurements shall be performed on
all field and central office splice points.

**4.2.2 [Method of Measurement]{.underline}:**

**4.2.2.1** Field splice loss measurements shall be made between the end
termination points at 1310 and/or 1550 nanometers for single mode fibers
and in accordance with Figure 14. Two splice loss measurements shall be
made between the end termination points. The first measurement shall be
from termination point A to termination point B. The second measurement
shall be from termination point B to termination point A.

**4.2.2.2** CO splice loss measurements shall be made at 1310 and/or
1550 nanometers for single mode fibers and in accordance with Figure 15.
Two splice loss measurements shall be made between the end termination
points. The first measurement shall be from termination point A to
termination point B. The second measurement shall be from termination
point B to termination point A.

**4.2.3 [Test Equipment]{.underline}:** The test equipment is shown in
Figures 14 and 15. The optical time domain reflectometer (OTDR) used for
the testing should have dual wave length capability.

**4.2.4 [Applicable Results]{.underline}:**

**4.2.4.1** The splice loss for each single mode field splice shall be
the bi-directional average of the two OTDR readings. To calculate the
actual splice loss, substitute the OTDR readings maintaining the sign of
the loss (+) or apparent gain (−) into the following equation:

OTDR Reading OTDR Reading

Actual Splice = [From A to B + From B to A]{.underline}

Loss (dB) 2

**4.2.4.2** When specified in the applicable construction contract, the
splice loss of each field splice at 1310 and/or 1550 nanometers shall
not exceed the limit specified in the contract.

**4.2.4.3** When no limit is specified in the applicable construction
contract, the splice loss of each field splice shall not exceed 0.2 dB
at 1310 and/or 1550 nanometers.

**4.2.4.4** The splice loss for each single mode CO splice shall be the
bi-directional average of the two OTDR reading. To calculate actual
splice loss, substitute the OTDR reading, maintaining the sign of the
loss (+) or apparent gain (−), into the equation specified in Paragraph
4.2.4.1 of this bulletin.

**4.2.4.5** When specified in the applicable construction contract, the
splice loss of each central office splice at 1310 and/or 1550 nanometers
shall not exceed the limit specified in the contract.

**4.2.4.6** When no limit is specified in the applicable construction
contract, the splice loss of each central office splice shall not exceed
1.2 dB at 1310 and/or 1550 nanometers.

**4.2.5 [Data Record]{.underline}:** The measurement data shall be
recorded. A suggested format similar to Format V, Outside Plant
Acceptance Test - Fiber Optic Telecommunications Plant, in Paragraph 7
of this bulletin or a format specified in the applicable construction
contract may be used.

**4.2.6 [Probable Causes for Nonconformance]{.underline}:** When the
results of the splice loss measurements exceed the specified limits the
following factors should be checked:

a\. Proper end preparation of the fibers;

b\. End separation between the fiber ends;

c\. Lateral misalignment of fiber cores;

d\. Angular misalignment of fiber cores;

e\. Fresnel reflection;

f\. Contamination between fiber ends;

g\. Core deformation; or

h\. Mode-field diameter mismatch.

**4.3 [End-to-End Attenuation Measurement]{.underline}:**

**4.3.1** After placement of all fiber optic cable plant has been
completed and spliced together to form a continuous optical link between
end termination points, end-to-end attenuation measurements shall be
performed on each optical fiber within the cable.

**4.3.2 [Method of Measurement]{.underline}:** For single mode fibers,
the end-to-end attenuation measurements of each optical fiber at 1310
and/or 1550 nanometers in each direction between end termination points
shall be performed in accordance with Figure 16.

**4.3.3 [Test Equipment]{.underline}:** The test equipment is shown in
Figure 16.

**4.3.4 [Applicable Results]{.underline}:** The end-to-end attenuation
of each single mode optical fiber at 1310 and/or 1550 nanometers shall
not exceed the limits specified in the applicable construction contract.

**4.3.5 [Data Record]{.underline}:** The measurement data shall be
recorded. A suggested format similar to Format V for fiber optic
telecommunications plant in Paragraph 7 of this bulletin or on a format
specified in the applicable construction contract may be used.

**4.3.6 [Probable Causes for Nonconformance]{.underline}:** Failure of
each optical fiber to meet the end-to-end attenuation limit could be
attributed to the following:

a\. Excessive field or central office splice loss;

b\. Excessive cable attenuation; or

c\. Damage to the fiber optic cable during installation.

**4.4 [End-to-End Fiber Signature Measurement]{.underline}:**

**4.4.1** After placement of all fiber optic cable plant has been
completed and spliced together to form a continuous optical link between
end termination points, end-to-end fiber signature testing shall be
performed on each optical fiber within the cable.

**4.4.2 [Method of Measurement]{.underline}:** For single mode fibers,
the end-to-end fiber signature measurement of each optical fiber in each
direction shall be performed between end termination points at 1310
and/or 1550 nanometers in accordance with Figure 17.

**4.4.3 [Test Equipment]{.underline}:** The test equipment is shown in
Figure 17.

**4.4.4 [Applicable Results]{.underline}:** The appearance of each
optical fiber between end termination points.

**4.4.5 [Data Record]{.underline}:** Plot the trace of each optical
fiber and retain as a permanent record for future comparison if needed.

**4.4.6 [Probable Causes for Nonconformance]{.underline}:** None.

**5. VOICEBAND DATA TRANSMISSION MEASUREMENTS**

**5.1** The data transmission measurements listed in this section shall
be used to determine the acceptability of trunk and nonloaded subscriber
loop circuits for data modem transmission.

**5.2 [Signal-to-C Notched Noise (S/CNN) Measurement]{.underline}:**

**5.2.1** When specified by the borrower, S/CNN measurements shall be
made on trunk circuits and nonloaded subscriber loops. For trunk
circuits, the measurement shall be made between CO locations. For
nonloaded subscriber loops, the measurement shall be made from the CO to
the station protector of the NID at the customer\'s access location.

**5.2.2** S/CNN is the logarithmic ratio expressed in dB of a 1,004 Hz
holding tone signal compared to the C-message weighted noise level.
S/CNN is one of the most important transmission parameters affecting the
performance of data transmission because proper modem operation requires
low noise relative to received power level. Since modulated carriers are
used in data communication systems, noise measurements need to be
performed with power on the connection to activate equipment having
signal-level-dependent noise sources. For 4 kHz channels, a 1,004 Hz
holding tone is used to activate the signal-dependent equipment on the
channel or connection.

**5.2.3 [Method of Measurement]{.underline}:** The S/CNN measurement
shall be made using a 1,004 Hz holding tone at −13 dBm0 (decibels
relative to one milliwatt, referred to a zero transmission level point)
and performed in accordance with American National Standards Institute
(ANSI) T1.506-1990, American National Standard for Telecommunications -
Network Performance - Transmission Specifications for Switched Exchange
Access Network including supplement ANSI T1.506a-1992, and American
National Standards Institute/Institute of Electrical and Electronics

Engineers(ANSI/IEEE) 743-1984, IEEE Standard Methods and Equipment for
Measuring the Transmission Characteristics of Analog Voice Frequency
Circuits.

**5.2.4 [Test Equipment]{.underline}:** The equipment for performing the
measurement shall be in accordance with ANSI/IEEE 743-1984.

**5.2.5 [Applicable Results:]{.underline}** The S/CNN for both trunk and
nonloaded subscriber loop circuits shall not be less than 31 dB.

**5.2.6 [Data Record]{.underline}:** The measurement data shall be
recorded. Suggested formats similar to Format VI, Voiceband Data
Transmission Tests - Nonloaded Subscriber Loops, and Format VII,
Voiceband Data Transmission Tests - Trunk Circuits, in Paragraph 7 of
this bulletin or formats specified in the applicable construction
contract may be used.

**5.2.7 [Probable Causes for Nonconformance]{.underline}:** Some of the
causes for failing to obtain the desired results may be due to excessive
harmonic distortion, quantizing noise, phase and amplitude jitter, and
loss in digital pads used for level settings.

**5.3 [Signal-to-Intermodulation Distortion (S/IMD)
Measurement]{.underline}:**

**5.3.1** When specified by the borrower, S/IMD measurements shall be
made on trunk circuits and nonloaded subscriber loops. For trunk
circuits, the measurement shall be made between CO locations. For
nonloaded subscriber loops, the measurement shall be made from the CO to
the station protector of the NID at the customer\'s access location.

**5.3.2** S/IMD is a measure of the distortion produced by extraneous
frequency cross products, known as intermodulation products, when a
multi-tone tone signal is applied to a system.

**5.3.3** Intermodulation distortion (IMD) is caused by system
nonlinearities acting upon the harmonic frequencies produced from an
input of multiple tones. The products resulting from IMD can be more
damaging than noise in terms of producing data transmission errors.

**5.3.4.** IMD is measured as a signal to distortion ratio and is
expressed as the logarithmic ratio in dB of the composite power of four
resulting test frequencies to the total power of specific higher order
distortion products that are produced. The higher order products are
measured at both the 2nd order and 3rd order and are designated R2 and
R3, respectively. The four frequency testing for IMD is produced with
four tones of 857, 863, 1,372, and 1,388 Hz input at a composite power
level of −13 dBm0.

**5.3.5 [Method of Measurement]{.underline}:** The S/IMD measurement
shall be performed in accordance with ANSI T1.506-1990 and ANSI/IEEE

743-1984.

**5.3.6 [Test Equipment]{.underline}:** The equipment for performing the
measurement shall be in accordance with ANSI/IEEE 743-1984.

**5.3.7 [Applicable Results]{.underline}:** The 2nd order (R2) S/IMD for
both trunk and nonloaded subscriber loop circuits shall not be less than
40 dB. The 3rd order (R3) S/IMD for both trunk and nonloaded subscriber
loop circuits shall not be less than 40 dB.

**5.3.8 [Data Record]{.underline}:** The measurement data shall be
recorded. Suggested formats similar to Format VI for nonloaded
subscriber loops and Format VII for trunk circuits in Paragraph 7 of
this bulletin or formats specified in the applicable construction
contract may be used.

**5.3.9 [Probable Causes for Nonconformance]{.underline}:** Some of the
causes for failing to obtain the desired results may be due to channel
nonlinearities, such as compression and clipping, which cause harmonic
and intermodulation distortion in a voiceband signal.

**5.4 [Envelope Delay Distortion (EDD) Measurement]{.underline}:**

**5.4.1** When specified by the borrower, EDD measurements shall be made
on trunk circuits and nonloaded subscriber loops. For trunk circuits,
the measurement shall be made between CO locations. For nonloaded
subscriber loops, the measurement shall be made from the CO to the
station protector of the NID at the customer\'s access location.

**5.4.2** EDD is a measure of the linearity or uniformity of the phase
versus frequency characteristics of a transmission facility. EDD is also
known as relative envelope delay (RED).

**5.4.3** EDD is specifically defined as the delay relative to the
envelope delay at the reference frequency of 1,704 Hz. EDD is typically
measured at two frequencies, one low and one high in the voiceband. The
low frequency measurement is made at 604 Hz. The high frequency
measurement is made at 2,804 Hz.

**5.4.4 [Method of Measurement]{.underline}:** The EDD measurement shall
be performed in accordance with ANSI T1.506-1990 and ANSI/IEEE

743-1984.

**5.4.5 [Test Equipment]{.underline}:** The equipment for performing the
measurement shall be in accordance with ANSI/IEEE 743-1984.

**5.4.6 [Applicable Results]{.underline}:** The EDD for both trunk and
nonloaded subscriber loop circuits at the low frequency of 604 Hz shall
not exceed 1,500 microseconds. The EDD for both trunk and nonloaded
subscriber loop circuits at the high frequency of 2,804 Hz shall not
exceed 1,000 microseconds.

**5.4.7 [Data Record]{.underline}:** The measurement data shall be
recorded. Suggested formats similar to Format VI for nonloaded
subscriber loops and Format VII for trunk circuits in Paragraph 7 of
this bulletin or formats specified in the applicable construction
contract may be used.

**5.4.8 [Probable Causes for Nonconformance]{.underline}:** Some of the
causes for failing to obtain the desired results may be due to
nonlinearity of the phase versus frequency characteristic of the
transmission facility. This nonlinear phase versus frequency
characteristic of the transmission facility causes the various frequency
components to travel at different transit times which results in
successively transmitted data pulses to overlap at the receive end. The
overlapping of the pulses at the receive end results in distortion of
the received signal. Excessive EDD on the transmission facility may be
reduced using data modems with equalization or by conditioning the
transmission line.

**5.5 [Amplitude Jitter (AJ) Measurement]{.underline}:**

**5.5.1** When specified by the borrower, AJ measurements shall be made
on trunk circuits and nonloaded subscriber loops. For trunk circuits,
the measurement shall be made between CO locations. For nonloaded
subscriber loops, the measurement shall be made from the CO to the
station protector of the NID at the customer\'s access location.

**5.5.2** AJ is any fluctuation in the peak amplitude value of a fixed
tone signal at 1,004 Hz from its nominal value. AJ is expressed in peak
percent amplitude modulation.

**5.5.3** AJ is measured in two separate frequency bands, 4 - 300 Hz and
20 - 300 Hz. The 4 - 300 Hz band is important for modems employing echo
canceling capabilities. The 20- 300 Hz band is used for modems that do
not employ echo cancelers.

**5.5.4** Amplitude modulation can affect the error performance of
voiceband data modems. The measurement of amplitude jitter indicates the
total effect on the amplitude of the holding tone of incidental
amplitude modulation and other sources including quantizing and message
noise, impulse noise, gain hits, phase jitter, and additive tones such
as single-frequency interference.

**5.5.5 [Method of Measurement]{.underline}:** The AJ measurement shall
be performed in accordance with ANSI T1.506-1990 and ANSI/IEEE

743-1984.

**5.5.6 [Test Equipment]{.underline}:** The equipment for performing the
measurement shall be in accordance with ANSI/IEEE 743-1984.

**5.5.7 [Applicable Results]{.underline}:** The AJ for both trunk and
nonloaded subscriber loop circuits in the 4 - 300 Hz frequency band
shall not exceed 6%. The AJ for both trunk and nonloaded subscriber loop
circuits in the 20 - 300 Hz frequency band shall not exceed 5%.

**5.5.8 [Data Record]{.underline}:** The measurement data shall be
recorded. Suggested formats similar to Format VI for nonloaded
subscriber loops and Format VII for trunk circuits in Paragraph 7 of
this bulletin or formats specified in the applicable construction
contract may be used.

**5.5.9 [Probable Causes for Nonconformance]{.underline}:** Some of the
causes for failing to obtain the desired results may be due to excessive
S/CNN, impulse noise, and phase jitter.

**5.6 [Phase Jitter (PJ) Measurement]{.underline}:**

**5.6.1** When specified by the borrower, PJ measurements shall be made
on trunk circuits and nonloaded subscriber loops. For trunk circuits,
the measurement shall be made between CO locations. For nonloaded
subscriber loops, the measurement shall be made from the CO to the
station protector of the NID at the customer\'s access location.

**5.6.2** PJ is any fluctuation in the zero crossings of a fixed tone
signal (usually 1,004 Hz) from their nominal position in time within the
voiceband. PJ is expressed in terms of either degrees peak-to-peak
(°p-p) or in terms of a Unit Interval (UI). One UI is equal to 360° p-p.

**5.6.3** PJ measurements are typically performed in two nominal
frequency bands. The frequency bands are 20 - 300 Hz band and either the
2 - 300 Hz band or the 4 - 300 Hz band. The 20 - 300 Hz band is
important to all phase-detecting modems. The 4 - 300 Hz band or the 2 -
300 Hz band is important for modems employing echo canceling
capabilities.

**5.6.4** Phase jitter can affect the error performance of voiceband
data modems that use phase detection techniques. The measurement of
phase jitter indicates the total effect on the holding tone of
incidental phase modulation and other sources including quantizing and
message noise, impulse noise, phase hits, additive tones such as
single-frequency interference, and digital timing jitter.

**5.6.5 [Method of Measurement]{.underline}:** The PJ measurement shall
be performed in accordance with ANSI T1.506-1990 and ANSI/IEEE

743-1984.

**5.6.6 [Test Equipment]{.underline}:** The equipment for performing the
measurement shall be in accordance with ANSI/IEEE 743-1984.

**5.6.7 [Applicable Results]{.underline}:** The PJ for both trunk and
nonloaded subscriber loop circuits in the 4 - 300 Hz frequency band
shall not exceed 6.5° p-p. The PJ for both trunk and nonloaded
subscriber loop circuits in the 20 - 300 Hz frequency band shall not
exceed 10.0° p-p.

**5.6.8 [Data Record]{.underline}:** The measurement data shall be
recorded. Suggested formats similar to Format VI for nonloaded
subscriber loops and Format VII for trunk circuits in Paragraph 7 of
this bulletin or formats specified in the applicable construction
contract may be used.

**5.6.9 [Probable Causes for Nonconformance]{.underline}:** Some of the
causes for failing to obtain the desired results may be due to excessive
S/CNN, impulse noise, and amplitude jitter.

**5.7 [Impulse Noise Measurement]{.underline}:**

**5.7.1** When specified by the borrower, impulse noise measurements
shall be made on trunk circuits and nonloaded subscriber loops. For
trunk circuits, the measurement shall be made between CO locations. For
nonloaded subscriber loops, the measurement shall be made from the CO to
the station protector of the NID at the customer\'s access location.

**5.7.2** Impulse noise is a measure of the presence of unusually large
noise excursions of short duration that are beyond the normal background
noise levels on a facility. Impulse noise is typically measured by
counting the number of occurrences beyond a particular noise reference
threshold in a given time interval. The noise reference level is
C-message weighted.

**5.7.3 [Method of Measurement]{.underline}:** The impulse noise
measurement shall be performed using a 1,004 Hz tone at -13 dBm0 and in
accordance with ANSI T1.506-1990 and ANSI/IEEE 743-1984.

**5.7.4 [Test Equipment]{.underline}:** The equipment for performing the
measurement shall be in accordance with ANSI/IEEE 743-1984.

**5.7.5 [Applicable Results]{.underline}:** The impulse noise for both
trunk and nonloaded subscriber loop circuits shall not exceed 65 dBrnC0
(decibels relative to one picowatt reference noise level, measured with
C-message frequency weighting, referred to a zero transmission level
point). The impulse noise requirement shall be based upon a maximum of 5
counts in a 5 minute period at equal to or greater than the indicated
noise thresholds.

**5.7.6 [Data Record]{.underline}:** The measurement data shall be
recorded. Suggested formats similar to Format VI for nonloaded
subscriber loops and Format VII for trunk circuits in Paragraph 7 of
this bulletin or formats specified in the applicable construction
contract may be used.

**5.7.7 [Probable Causes for Nonconformance]{.underline}:** Some of the
causes for failing to obtain the desired results may be due to excessive
transient signals originating from the various switching operations.

**6. SHIELD OR ARMOR GROUND RESISTANCE MEASUREMENTS**

**6.1** Shield or armor ground resistance measurements shall be made on
completed lengths of copper cable and wire plant and fiber optic cable
plant.

**6.2 [Method of Measurement]{.underline}:**

**6.2.1** The shield or armor ground resistance measurement shall be
made between the copper cable and wire shield and ground and between the
fiber optic cable armor and ground, respectively. The measurement shall
be made either on cable and wire lengths before splicing and before any
ground connections are made to the cable or wire shields or armors.
Optionally, the measurement may be made on cable and wire lengths after
splicing, but all ground connections must be removed from the section
under test.

**6.2.2** The method of measurement using either an insulation
resistance test set or a dc bridge type megohmmeter shall be as shown in
Figure 18.

**6.3 [Test Equipment]{.underline}:**

**6.3.1** The shield or armor ground resistance measurements may be made
using an insulation resistance test set, a dc bridge type megohmmeter,
or a commercially available fault locator.

**6.3.2** The insulation resistance test set should have an output
voltage not to exceed 500 volts dc and may be hand cranked or battery
operated.

**6.3.3** The dc bridge type megohmmeter, which may be ac powered,
should have scales and multipliers which make it possible to accurately
read resistance values of 50,000 ohms to 10 megohms. The voltage that is
applied to the shield or armor during the test should not be less than
\"250 volts dc\" nor greater than \"1,000 volts dc\" when using an
instrument having adjustable test voltage levels.

**6.3.4** Commercially available fault locators may be used in lieu of
the above equipment, if the devices are capable of detecting faults
having resistance values of 50,000 ohms to 10 megohms. Operation of the
devices and method of locating the faults should be in accordance with
manufacturer\'s instructions.

**6.4 [Applicable Results]{.underline}:**

**6.4.1** For all new copper cable and wire facilities and all new fiber
optic cable facilities, the shield or armor ground resistance levels
normally exceed 1 megohm-mile (1.6 megohm-km) at 68°F (20°C). A value of
100,000 ohm-mile (161,000 ohm-km) at 68°F (20°C) shall be the minimum
acceptable value of the shield or armor ground resistance.

**6.4.2** Shield or armor ground resistance varies inversely with length
and temperature. In addition other factors which may affect readings
could be soil conditions, faulty test equipment and incorrect test
procedures.

**6.4.3** For the resistance test method and dc bridge type megohmmeter,
the ohm-mile (ohm-km) value for the shield or armor ground resistance
shall be computed by multiplying the actual scale reading in ohms on the
test set by the length in miles (km) of the cable or wire under test.

**6.4.4** The objective shield or armor ground resistance may be
determined by dividing 100,000 by the length in miles (161,000 by the
length in km) of the cable or wire under test. The resulting value is
the minimum acceptable meter scale reading in ohms. Examples for
Paragraphs 6.4.3 and 6.4.4 of this bulletin are as follows:

Equation 1. Test Set

Scale Reading \* Length = Resistance-Length

75,000 ohms \* 3 miles = 225,000 ohm-mile

(75,000 ohms \* 4.9 km = 367,000 ohm-km)

Equation 2. 100,000 ohm-mile ÷ Length = Minimum Acceptable

Meter Scale Reading

100,000 ohm-mile ÷ 3 miles = 33,333 ohms

(161,000 ohm-km ÷ 4.9 km = 32,857 ohms)

**6.4.5** Since the 33,333 ohms (32,857 ohms) is the minimum acceptable
meter scale reading and the meter scale reading was 75,000 ohms, the
cable is considered to have met the 100,000

ohm-mile (161,000 ohm-km) requirement.

**6.4.6** Due to the differences between various jacketing materials
used in manufacturing cable or wire and to varying soil conditions, it
is impractical to provide simple factors to predict the magnitude of
variation in shield or armor to ground resistance due to temperature.
The variations can, however, be substantial for wide excursions in
temperature from the ambient temperature of 68°F (20°C).

**6.5 [Data Record]{.underline}:** The data shall be corrected to the
length requirement of ohm-mile (ohm-km) and a temperature of 68°F (20°C)
and shall be recorded on a form specified in the applicable construction
contract.

**6.6 [Probable Causes for Nonconformance]{.underline}:**

**6.6.1** When results of resistance measurements are below the 100,000
ohm-mile (161,000 ohm-km) requirement at 68°F (20°C), the jacket
temperature, soil conditions, test equipment and method shall be
reviewed before the cable or wire is considered a failure. If the
temperature is approximately 68°F (20°C) and soil conditions are
acceptable, and a reading of less than 100,000 ohm-mile (161,000 ohm-km)
is indicated, check the calibration of the equipment; as well as, the
test method. If the equipment was found to be out of calibration,
recalibrate the equipment and remeasure the cable or wire. If the
temperature was 86°F (30°C) or higher, the cable or wire shall be
remeasured at a time when the temperature is approximately 68°F (20°C).
If the test was performed in unusually wet soil, the cable or wire shall
be retested after the soil has reached normal conditions. If after
completion of the above steps, the resistance value of 100,000 ohm-mile
(161,000 ohm-km) or greater is obtained, the cable or wire shall be
considered acceptable.

**6.6.2** When the resistance value of the cable or wire is still found
to be below 100,000 ohm-mile (161,000 ohm-km) requirement after
completion of the steps listed in Paragraph 6.6.1 of this bulletin, the
fault shall be isolated by performing shield or armor ground resistance
measurements on individual cable or wire sections.

**6.6.3** Once the fault or faults have been isolated, the cable or wire
jacket shall be repaired in accordance with RUS Bulletin
1753F-401(PC-2), "RUS Standard for Splicing Copper and Fiber Optic
Cables," or the entire cable or wire section may be replaced at the
request of the borrower.

**7. DATA FORMATS**

**7.1** The following suggested formats listed in this section may be
used for recording the test data: