Programmable alarm system

The invention involves a programmable alarm system including a local communicator having one or more sensors responsive to problem situations such as illegal intrusion, fire, panic or the like, which can be installed in a residence, office or other premises to sense a problem situation, and after conversion to a digital format transmit the information through a telephone line to a central receiver for temporary and permanent display of the location of the residence or other premise and the particular problem encountered. The communicator operation and sensor characteristics can be programmed for each location by temporary attachment of a programmer unit, thus to provide flexibility. In addition, in the event that the integrity of the system is interrupted (e.g., line severance), a separate redundant system is rendered operative to indicate the problem situation.

FIELD OF THE INVENTION 
The present invention relates generally to communication systems and more 
particularly to a programmable alarm system which includes a local 
communicator that can be installed in a residence, shop, office building, 
or on other premises to sense various problem situations (fire, burglary, 
panic or the like) and to transmit correlated digital information through 
existing dial-switched telephone lines or separate private lines to a 
central receiver station so that appropriate agencies (e.g. police, fire, 
hospital or the like) can be immediately informed of the type and location 
of the sensed problem. 
BACKGROUND OF THE INVENTION 
A rather large number of alarm systems are presently manufactured to 
provide protection against various problem situations which may be 
experienced in a residence, an office or shop building, or any other 
premises. Fire, burglary, panic, or any other unique situation can be 
sensed locally and the information then transmitted by a local 
communicator through appropriate connection to the local telephone lines 
for transmission to a receiver located at a suitable central location, so 
that the information can in turn be relayed to the appropriate agency 
(e.g. fire department, police department) or other desired recipient. 
While all these systems are generally effective, there are certain 
problems, the most significant of which is the lack of flexibility of the 
units. For example, most existing communicators include "hard wiring" to 
meet the particular requirements of a given installation. This 
"customization" not only increases initial cost but also presents a 
problem if the protective circuits are to be changed or modified. 
Typically again, a practical problem is encountered at the central 
receiving station because of the time involved in communication of a given 
alarm so that a limited number of local communicators can be connected to 
a single central receiver, thus further increasing not only initial cost 
but subsequent maintenance. 
Furthermore, since the alarm reporting is dependent upon the integrity of 
the telephone line, if, for example, a burglar were to cut the telephone 
line prior to his entry, no information would thereafter be transmitted to 
the central location so that the entire security system would break down. 
SUMMARY OF THE PRESENT INVENTION 
Accordingly, it is the general objective of the present application to 
provide a programmable alarm system, including a digital communicator at 
each local station containing a memory which can be programmed by a 
detachable programmer unit to meet a wide variety of user requirements, 
and can moreover be modified at any time when such requirements change. 
While such a communicator is compatible through appropriate phone line 
connection to any one of a number of central station receivers, when 
conjoined with a particular receiver at the central station embodying the 
present invention, a more rapid rate of information delivery is provided. 
In the event that the integrity of the digital communicator-central 
station system is interrupted, in accordance with an additional objective 
of the invention, a separate, redundant transmission from a multiplexer 
transmitter associated with the digital communicator is established to a 
central receiver through a separate private line. 
To achieve such objectives, the communicator unit can be readily connected 
to a plurality of alarm sensors, typical examples being a simple panic 
button, a fire sensor, a motion detector, window foils, door switches and 
the like. The sensed information from any of the sensors is processed by 
the communicator into digital format and then delivered through suitable 
connection to the local telephone line for transmission to a central 
receiver which generally provides for a temporary visual display of the 
received information, together with a printed output providing a permanent 
record of the information received. 
In addition to reports of an alarm, the communicator unit is arranged to 
also report any trouble such as a sensor malfunction or discontinuity of 
sensor wiring, and a restoral report when such malfunction has been 
corrected, or the alarm condition returned to normal. 
In accordance with a significant aspect of the present invention, the 
communicator unit is adapted for temporary connection to a programmer unit 
enabling the installer to quickly insert variable information into the 
memory portion of the communicator, such as, for example, the phone number 
to be dialed, the user account number, and the appropriate trouble and 
restoral reports, together with the character of the communicator 
operation related to activation of each particular alarm sensor. Once the 
memory portion of the communicator has been so programmed, the programmer 
unit can be removed and utilized for other installations, each of which 
can accordingly be customized in accordance with the needs and 
requirements of the particular user without any rewiring or other 
modification of the communicator unit itself. 
Furthermore, as will be obvious, if any changes are to be made, the 
programmer can once again be connected to the communicator and the entire 
operational program can be changed, or the program of an individual sensor 
or other specific data can be modified as required. 
Additionally, if any problems arise in the communicator, the programmer 
unit can be temporarily connected thereto with the capability of providing 
a test operation which will display the status of any selected data, thus 
allowing modification, if indeed an undesired situation appears. In 
particular, the status of each sensor, and more particularly its sensing 
loop circuit, can be immediately checked as to its condition of being 
normal, open or shorted, thus facilitating any necessary trouble shooting 
and/or repair. 
In accordance with an additional important aspect of the present invention, 
the communicator unit, and more particularly the individual sensors, can 
be selectively activated or armed. For example, if a residence is 
occupied, perimeter zones such as doors and windows can be selectively 
armed while other internal zones (motion detectors or mats) within the 
residence can be inactive, thus precluding false reports resultant from 
the activities of the occupants of the residence. 
While the communicator can be entirely armed (activated) or disarmed at a 
point interior or exterior to the premises, for example by a simple key 
switch, in accordance with another aspect of the invention, the 
communicator can be programmed to accept arming or disarming from a 
digital key-pad which can be placed at any convenient location and enables 
the arming or disarming to occur only when numerical digit keys with a 
combination of up to eight digits, known of course only to the owners or 
occupants of the residence or other establishment, are depressed or 
punched in appropriate sequence. This key-pad data can also be checked by 
the test function of the programmer. 
While the programmed communicator can be arranged to transmit information 
to any of a number of existent central receivers, it is particularly 
useful when utilized in connection with a central receiver embodying the 
present invention. In the first place, when the communicator is programmed 
for use with such receiver, it automatically sends or transmits the 
information at more than twice the rate of other communicators, and also 
allows a five digit report wherein the first four digits provide the 
requisite information and the final digit provides parity information that 
is an automatic check on the proper transmission, thus obviating the 
necessity for a double or multiple transmission of a report, as is 
customary with most existent alarm systems. 
As the information is received at the central receiver, it is displayed to 
indicate the line number, the particular account number, the reporting 
zone, and the nature of the transmission. In addition, the receiver 
incorporates a printer which automatically records in chronological 
sequence the reports received from all of the local communicators 
connected thereto, including the data, time, line number, account number, 
and the message by zone in an easy-to-read alpha-numeric printout. More 
particularly, it will distinguish between alarms, openings, closings, 
trouble and restoral reports. If the particular account communicator 
incorporated a local listen-in arrangement, the audio information will 
also be heard at the receiver. 
An accessory unit is arranged for optional releasable connection to each 
communicator unit after the programmer unit has been disconnected through 
the same connection arrangement, and in accordance with the additional 
security objective of the invention, establishes connection and one-way 
transmission through a separate private line to a central multiplex 
receiver capable of receiving inputs from a number of communicator 
accessory units (e.g. 24 units). Normally, a unique frequency tone is 
transmitted, but if any alarm condition occurs the frequency changes, thus 
to indicate the existence of the "alarm" condition at the receiver. 
Furthermore, if a trouble condition occurs (e.g. telephone line break, 
communicator unit malfunction or the like), the normal frequency tone will 
not exist and its absense will be suitably indicated at the receiver. 
Thus, a redundant double-check and foolproof system is provided. 
While this accessory unit was designed as a complementary unit to the 
digital communicator system, it will be immediately understood by those 
skilled in the art that the unit can be appropriately connected directly 
to alarm sensing units and thus used as an alarm system by itself.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENT OF THE INVENTION 
With initial reference to FIG. 1, the programmable alarm system, as 
generally illustrated, includes a communicator unit 10 which can be 
physically installed at any convenient location within a residence, 
office, shop building, or any other premises that are to be protected. A 
plurality of sensor inputs 12 are connected to the communicator 10 to 
initiate various alarm reports such as fire, burglary, panic, motion 
detection or the like, and to also provide trouble and restoral inputs 
indicating a malfunction and its correction. 
A control key-pad unit 14 which can be located interiorly or exteriorly of 
the premises includes a plurality of digit keys which can be programmed to 
provide a sequential combination for arming (activating) or disarming the 
communicator unit with appropriate time delays for entry or exit from the 
premises by its normal occupants without instigating an alarm. 
When activated, the communicator unit 10 will convert the sensed data into 
a digital format for transmission through appropriate connection to a 
local telephone line L1, which can also be connected to a telephone T at 
the premises, for ultimate delivery to a central receiver 16, whereat the 
place and character of the reported alarm is displayed both on a temporary 
visual display and a permanent printed record, as will be described in 
more detail hereinafter. Also, any alarm signal can be utilized to 
activate a bell or other local audio or visual indicator 18, if desired 
and so programmed. 
In the event that the telephone line is cut or the communicator unit 10 
itself malfunctions, additional security can be provided by a separate and 
economical multiplex system which includes a multiplex transmitter 11 that 
can be easily connected to the communicator unit 10 by a suitable plug-in 
arrangement indicated at 13 in FIG. 1. The transmitter 11 delivers a 
predetermined frequency tone through a separate private line L2 to a 
multiplex receiver 15 under normal conditions, but the frequency will 
change if an alarm condition occurs and the normal tone will cease if the 
communicator unit 10, in some fashion, is disabled. Thus, a separate, 
redundant indication of the general security situation at the local 
premises is provided. 
The communicator unit 10 includes a memory which can be programmed by a 
programmer unit 20, which preferably is one that can be temporarily 
connected to the communicator unit 10 at the plug-in arrangement 13, to 
control the precise nature of the outputs to the central receiver 16 and 
can thereafter be disconnected from the communicator unit 10 so that the 
same will thereafter function in accordance with the programmed data. At 
any time, the programmer unit 20 can be reconnected if any changes or 
modifications in the reported information and its character are desired, 
and it will also be noted that the same programmer unit 20 can also be 
utilized to program any other communicator units 10 of the same type, thus 
reducing the installation or modification equipment requirement to a very 
large degree while at the same time providing for full flexibility of the 
local alarm reporting characteristics. 
Physically, the communicator unit 10, as shown in FIG. 2, can constitute a 
rather small housing 30, no more than one foot square and three inches in 
depth. It can be mounted on a wall or any other similar location where 
convenient, and preferably is closed at the front by a pivoted door 32 
with a key lock 34, so that no tampering with the unit is possible without 
key access. The electronic circuitry is mounted within the housing 30 
behind a face plate 36 provided with appropriate indicia for simplifying 
the appropriate connections to the communicator unit 10. More 
particularly, two terminals 38, 40 are provided at the lower left for 
connection with a small standby battery 42 in the event of power failure, 
power in the form of a 12-VAC input being normally supplied through 
connecting screw-terminals 44, 46 at the upper left of the unit. Also at 
the upper left are additional screw-terminals 48, 50, 52 for providing an 
auxiliary power output or 6 VDC for a local bell connection. Below these 
screw-terminals are several terminals 54 for connection to a standard 
telephone jack 55, enabling the output of the communicator 10 to be 
established with the telephone line L1. Across the bottom of the unit are 
twelve screw-terminals 56 for appropriate connection of the input sensors 
in the form of circuit loops, as diagrammatically indicated on the face 
plate and as will be described hereinafter, and on the right of the unit 
are a number of screw-terminals 58, as indicated on the face plate, for 
connection of control units as the digital key-pad previously mentioned 
and other arming or activating connections. 
While not shown in FIG. 2, a plurality of connecting sockets are provided 
at the top of the communicator unit 10, enabling the mentioned plug-in 
connection 13 of the programmer unit 20, illustrated in FIGS. 3 and 4, and 
the separate multiplex transmitter 11 shown in FIG. 7. 
The electrical circuits of both the communicator unit 10 and the programmer 
unit 20 which can be temporarily connected thereto are shown in the block 
diagram of FIGS. 4A and 4B. More particularly, the communicator unit 10 is 
connected by the previously described screw-terminals 56 to one or more 
particular sensors. As shown in FIG. 4A specifically, one connection is 
made to a fire sensor 62 which takes the form of a loop circuit that can 
be shorted by any standard fire detection unit such as a thermostat, an 
ionization detector, or any other available sensing mechanism, to 
instigate an alarm report. More particularly, as shown, the loop circuit 
of the fire sensor 62 is terminated by a 1,000 ohm resistor 64, and is 
electrically arranged to report a short if the total resistance across the 
loop is less than 500 ohms, or to indicate an "open" circuit if a 
resistance higher than 1,500 ohms exists. The second sensor 66 illustrated 
is a "panic" sensor in the form of another resistance-terminated loop 
circuit with two buttons 68 located at various desired positions within a 
residence, enabling the occupant to manually instigate an alarm whenever 
it is desired by the mere pushing of any button 68. A third sensor loop 
circuit 70 provides a perimeter intrusion sensor such as a window foil 72, 
and a fourth sensor 76 provides an interior intrusion sensor which could 
be, for example, in the form of an electrified floor mat 78. 
All of the sensors are connected to multiple protective networks 80 which 
electrically take the form of resistance-capacity circuits (time 
constants) which will suppress transients on the inputs from the sensors 
to preclude false alarms. Master (full) or partial arming or activating of 
the communicator from a key switch 81 or the like at some internal or 
external perimeter location and connected to the protective networks 80 by 
two of the terminals 58 provides additional control signals. The arming 
signals are connected though an indicator driver 83 which constitutes a 
current-limited switch to a control processing unit 86 and to arming 
status indicators 85 in the form of light-emitting diodes on the panel. 
All of these input signals are delivered to an analog multiplexer 82 which 
routes any one of the input signals to a comparator 84. More particularly, 
the signals delivered to the analog multiplexer 82 include the voltage on 
each of the multiple sensor loops, the voltage on the master arming input 
or on the perimeter arming input, the battery voltage status, audio input, 
and forced arming input. The comparator 84 sets thresholds or limits, both 
high and low, on the output of the analog multiplexer 82 and delivers its 
signal outputs, uniquely correlated with the various input signals, to the 
control processing unit 86, which controls delivery of data from memory 
units 88, 90, 92 in a manner to be described hereinafter, to a data output 
latch 94 (FIG. 4B). The memory units include a read-only memory 88 
containing program instructions in integrated circuits allowing the unit 
to provide the general alarm operation, a random access memory 90 which 
provides temporary storage for data generated by the control processor, 
and a variable random access memory 92 which stores variable program 
parameters introduced from the programmer unit 20 including: 
1. Frequency and timing table addresses for parameters to be used in 
communicating with various central station receivers. 
2. Phone number to be dialed. 
3. Subscriber account number. 
4. Digits to be sent on the occasion of: trouble, restoral, opening, 
closing. 
5. Time delays for entry and exit. 
6. Entry delay prewarning enable. 
7. Bell cutoff time. Bell test enable. 
8. Listen in timer. 
9. Miscellaneous options: Arming light blink, Phone callout try limit, 
Battery report suppression, Trouble and restoral report expansion, Fault 
list with closing report. 
10. Combination for digital key-pad arm/disarm. 
11. Delays for the key-pad entry and penalty. 
12. Sensor loop operation codes. 
In the event of power failure, a back-up battery 96 preserves the 
programmed data in this memory unit 92. 
The information from the data output latch 94 is delivered to a plurality 
of current amplifiers 98 which constitute transistor relay drivers which 
supply the current necessary to activate various relays, such as a dial 
pulse relay 100, which, under control of the processor 86, opens or closes 
a dial telephone line in a manner simulating the dialing of a telephone. 
The current amplifiers 98, under control of the processor 86, also 
activate a line seize relay 102 which isolates the telephone L1 on a 
protected premise while a report is being made, and a bell control circuit 
103 for the mentioned alarm bell 18. Audio signals, including an input 
from a local microphone 105, are delivered through an audio amplifier 107 
and a coupling transformer 97 to the phone line L1, and data are delivered 
by the data latch 94 through a transmit amplifier shaper 95 which 
suppresses harmonics to the coupling transformer 97. Input audio signals 
from the telephone line L1 such as the dial tone are, in turn, delivered 
by the transformer 97 to a receive audio amplifier 99 which receives and 
amplifies audio signals for delivery to the analog multiplexer 82, and 
ultimately to the processor unit 86. 
The control processing unit 86 also is provided with an input from a clock 
crystal 104 which constitutes an oscillator that essentially determines 
the timing and frequency functions of the entire communicator; for 
example, the timing of any entry delay, exit delay, bell cutoff, phone 
dialing make and break, etc., as well as the message transmission tone 
(frequency) and frequency discrimination enabling detection of the dial 
tone and acknowledge tone, as will be explained in more detail 
hereinafter. 
The entire communicator unit is energized by 12 VAC which is delivered from 
a transformer 106 connected to a standard 110-VAC source through a battery 
charger 108 which constitutes a current-limited voltage regulator, which 
provides the power for normal system operation and also is connected to 
the mentioned standby battery 42 to provide power to operate the system 
whenever a temporary power outage occurs. 
If, for any reason, the system supply voltage drops below the minimum 
necessary for proper operation, a low voltage cutoff sensor 112 is 
activated to disable the data output latch 94, the variable random access 
memory 92, and also the bell control circuit 103. This bell control 
circuit 103 is normally arranged to inhibit bell operation if the 
initiating signal occurs within about 30 seconds of a power-on reset, and 
such inhibition continues until the bell initiating signal from the 
processor has been removed for about 30 seconds. This prevents a defective 
battery which will not support bell operation from disabling the operation 
of the entire communicator. A battery voltage sensor 114 is also connected 
to determine the system voltage and delivers such sensed information to 
the analog multiplexer 82, and ultimately to the control processing unit 
86. The data output latch 94 also delivers processed data to an amplifier 
116 which supplies current to an indicator buzzer 118 on the circuit board 
of the communicator unit and any other externally located indicators, for 
example, on the key-pad control unit 14, its output being current limited 
to preclude damage by any short circuits. 
In order to program the communicator unit 10, and more particularly the 
variable random access memory unit 92 therein, the mentioned programmer 
unit 20 as physically shown in FIG. 3 is detachably connected by the 
mentioned plug-in arrangement 13 to the communicator unit 10 to establish 
the electrical connections as diagrammatically illustrated in FIG. 4B. The 
front of the programmer unit 20 mounts a plurality of data entry keys or 
buttons, including 15 keys 120 designated by the single digit numerals 0-9 
and letters b, C, d, E and F, and five control keys 122, arranged upon 
sequential depression to close various circuits, whose functions will be 
explained in detail hereinafter, and the data so entered is displayed in a 
nine-digit visual display window 124 located immediately thereabove. The 
face of the programmer unit also is provided with printed indicia 
indicating briefly the character of the data which should be entered 
during programming operation so as to remind the installer of the 
necessary sequence in the programming steps. 
Basically, for each sequential entry, appropriate control and digit keys 
120, 122 are designated so that the data related to a program code 
pre-established in a read-only memory unit 126 is delivered through 
interconnections 128, 130 with the alarm unit to the control processing 
unit 86 therein, which enables introduction of the programmed data to be 
stored into the variable random access memory unit 92 in the alarm system 
itself. The control data is delivered through additional connections 131, 
132 between the programmer and communicator units to a data output latch 
134 which energizes a standard seven-segment display for each digit in the 
nine-digit display window 124. The digits are sequentially illuminated by 
a counter decoder 136 which controls a digit cathode driver 137. Each time 
an output instruction is issued to the output data latch 134, the counter 
decoder 136 is incremented. The counter is reset by the last (seventh) 
output line of the processor. Additionally, the outputs of the counter 
decoder 136 apply a voltage to one side of each key switch 120, 122. When 
a key is depressed, this voltage is applied to control a sense input of 
the processor 86. 
The control keys 122, as indicated on the front of the programmer unit 20, 
have the following functions: 
SEL (Select) 
Depression of this key will display "SELEC" in the window. A number or 
letter key may now be pressed on the digital keyboard which will display 
the corresponding line of information. For example, pressing the "SEL" key 
and then the "3" will effect display of the selected phone number. When 
the programmer unit 20 is first connected to the communicator unit 10, 
"SELEC" should appear. 
TST (Test) 
Depression of this key displays the loop status of the individual sensed 
zone or area. If normal, a "-" will appear; if open, an "O", and if 
shorted, an "S". 
CLR (Clear) 
Depression of this key clears all data from a line and must be pressed 
before reprogramming that line. When "CLR" and "SEL" are pressed at the 
same time, the entire program will be erased in the random access memory 
unit 92. 
ENT (Enter) 
Depression of this key will display the next line of data, and a flashing 
cursor will indicate where further key input data will be entered. 
.fwdarw. (Advance) 
Depression of this key advances the cursor across the particular line. 
While the keys G, d, b, E and F supplement the digit keys numbered 0-9 so 
that a selection of 15 digit keys is enabled, these lettered keys also 
allow the introduction of certain specific data as follows: 
C (pause) 
This key may be depressed at any position to provide for a three-second 
pause. For example, it may be depressed when a noisy telephone line exists 
and would otherwise cause premature dialing. 
d (dial tone wait) 
This key may be depressed at any position to provide for a second dial tone 
wait. For example, nine-d-two-one-two (9d212) dials a nine, waits for a 
dial tone, then dials area code 212. 
b (bell cutoff time) 
Anywhere from two to ninety-nine minutes can be entered by pressing the 
appropriate digits. This key can be used also to provide for a bell test. 
If a small "b" is entered and a momentary arming station is held in the 
activated position for three seconds, the bell will ring until the switch 
is released. 
E (pre-warning-expanded report) 
This key constitutes a pre-warning enable switch which activates the buzzer 
during any entry delayed time, thus to function as a reminder to the 
occupant to disarm the system, and also provides, after a trouble or 
restoral report, designation of the zone. 
F (fault) 
The fault key will cause an inventory of all faulted zones to be 
transmitted with a closing report. 
A typical residential program would be programmed as follows, utilizing the 
fire, panic, exterior and interior intrusion loops as indicated 
diagrammatically in FIG. 4A. The identifying letters shown in parentheses 
will appear upon sequential depression of the "ENT" key and the other data 
then entered by selective key depression. 
__________________________________________________________________________ 
LINE 
DISPLAY 
MEANING 
__________________________________________________________________________ 
1 (CS) 55 
Set up for one round superspeed transmission 
in accordance with the present invention 
2 (P) 1C800 
Dial 1; pause 3 seconds; dial 800. 
3 (Ph)6367285 
Dial 6367285; the central station number. 
4 (ACC) 123 
Account number 123. 
5 (t)F (r)E E 
Send code F (15 pulses) for a trouble report; 
send code E (14 pulses); use the expanded reporting 
format to specify which zone has troubled or restored. 
Send no opening or closing reports. 
6 (OP) (CL) 
No opening or closing reports are transmitted. 
7 (di)40 (do)20 
Give an entry delay of 40 seconds; give an exit 
delay of 20 seconds. 
8 (PrE) E 
Sound the pre-warning during the entry delay. 
9 (bELL) 10 
Turn the bell off after 10 minutes of ringing. 
0 (LIS) No entry; no listening device in use. 
b (A) (P) (L) 
No entries on this line unless a limit of eight tries on 
a callout is desired. Enter 8 after the P. 
C (C)E05 dL 
The combination must be entered in five seconds. 
(LOOP 1)314 
A fire loop to be used in conjuction with the fire 
module for approval. Gives a zone 1 alarm with 
pulsed bell any time the loop is shorted. Gives 
a zone 1 trouble report any time the loop opens or 
either side is grounded. The buzzer will sound as 
long as the loop is in either the trouble or alarm 
state. No restoral reports are generated. 
(LOOP 2)311 
A panic button loop. Shorting the loop with a panic 
button gives an instant silent alarm. An open in the 
loop gives a trouble report. 
(LOOP 3)583 
A perimeter intrusion loop. Armed by either the 
key-pad, MA terminal or the PA terminal. Gives 
an entry delay on an open or short. Sends an alarm 
and gives a steady bell ring after the entry delay if 
the user does not disarm the system. Buzzer sounds 
during the entry delay. Exit delay on master arm; 
no exit delay on perimeter arm. 
(LOOP 4)513 
An interior intrusion loop. Armed only by the key-pad 
or MA terminal. Exit delay on arming; no entry delay. 
Instant alarm on open or short when armed. Bell rings 
on alarm. 
__________________________________________________________________________ 
By way of explanation, before the new program is to be entered, momentarily 
the SEL and CLR buttons are depressed, which erases all of the old 
information previously in the unit and displays "SELEC" on the visual 
display. The ENT button is then depressed, which will open the system for 
the display on line one and enter CS on the display. If the receiver 
embodying the present invention is used, the numeral keys 5 and 5 are 
pushed to automatically set up a system for the superspeed transmission 
permitted by this receiver. More particularly, the initial "5" entry 
establishes the pulse frequency requisite for the receiver of the present 
invention, which is twice that of other systems, and the second "5" entry 
sets the five-digit transmission format wherein the first four digits 
provide the information and the fifth digit provides the parity check, 
obviating the necessity for repeat transmission and thus reducing 
transmission time. Briefly, a transmission rate better than four times 
other systems is enabled. 
The operation of the fifth parity digit briefly is as follows. Each of the 
first four digits requires between one and fifteen pulses. The fifth digit 
is programmed so that the sum of all five is a multiple of fifteen, and if 
such fifteen multiple is delivered to the receiver, it automatically 
acknowledges a correct receipt of information, signalling to the 
communicator unit 10 that no further transmission is required. Otherwise, 
a repeat message will be transmitted. 
After this has been entered, the phone prefix entry is entered by first 
depressing the entry "ENT" key to display the "P", then the numeral "1", 
followed by depressing the "C" key to provide a three-second pause, and 
then depressing the digit keys in turn, 800, which constitutes the area 
code desired. The "ENT" key is again depressed, which allows line 3 to be 
entered, which in this residential program constitutes the phone number of 
the central station and includes a sequential depression of the following 
digit keys: 636 7285. 
The "ENT" button is again depressed and the account number can be entered 
by sequential depression of the digits 1, 2 and 3. In certain cases, 
instead of numerical digits for the account number (e.g. 1, 2, 3) the 
first digit can constitute one of the letters b, C, d, E or F, in which 
case the particular subscriber can utilize the mentioned microphone 105 
and the central receiver can incorporate a "listen-in" feature. It is to 
be particularly noted that since 15 keys can be utilized in three digit 
combinations, a theoretical limit of 15.sup.3 or 3,375 accounts can be 
accommodated. 
After a successive depression of the "ENT" key, the key "F" can be 
depressed for a trouble report, key "E" for a restoral report, and "E" 
again for an expanded report. The "ENT" key is again depressed, but 
because no opening or closing reports are required, no additional digits 
need be depressed. If, for example, such reports were required, key "b" 
could be depressed as an opening report and key "C" for a closing report, 
and if required, the "F" key can be depressed to indicate that all faulted 
zones would be reported at the closing. The "ENT" key is again depressed, 
and after a delay of 40 seconds and an exit delay of 20 seconds similarly 
entered by depression of the numerical keys. 
Thereafter, again, depression of the "ENT" key pre-warn entry can be 
achieved by depressing the "E" key, and in turn by depression of the "ENT" 
and "b" keys and a double digit entry from 2 to 99 minutes can be entered, 
and in the present case has been entered as 10 minutes of ringing. 
After repeated depression of the "ENT" key, a listening time between two 
and nine minutes, if used, can be entered. No entries are usually made on 
the subsequent line unless a limit of eight tries on a callout is desired, 
in which case "8" would be entered. 
The next entry line enables the particular key-pad combination up to eight 
digits to be entered, and on the following line the time allowed for the 
combination to be entered, and the permitted delay after a wrong digit 
(e.g. 5 seconds). 
When the "ENT" key is again depressed, the programming of the sensors (or 
sensing loops) can be instigated, and in accordance with a particularly 
advantageous aspect of the present invention, a three-digit code can be 
set up for each sensor. In the fire sensor (Loop I), the "3" key indicates 
that any opening in the fire circuit loop indicates trouble, the master 
arming or second digit is established by depressing the "1" key which 
provides for an instant alarm, and the numeral "4" key subsequently 
depressed provides for a pulsed bell. 
In turn, depression of the "ENT" key allows Loop 2 to be programmed. In 
this case, it is a panic button loop and depression of the "3" key 
provides for a trouble report if the circuit has been opened, the "1" key 
depression provides a short in the loop which provides an instant alarm, 
which, however, in accordance with the depression of the third digit, as 
the "1" key, provides for a silent alarm. Similarly, the Loop 3 and Loop 4 
are programmed and the system is then ready for operation. It is to be 
particularly noted that the operation and character of each loop sensor 
can be reprogrammed whenever desired so that great flexibility in the loop 
programming is enabled for all installations. 
Any output signals from the digital communicator 10 are delivered through 
the phone line L1 to the central receiver 16 whose physical appearance is 
substantially as shown in FIG. 5, providing certain display and control 
functions. More particularly, a visual display 140 at the top of the unit 
presents information as to the line number, the account number, and the 
particular zone to the operator. Four incoming lines can be processed 
simultaneously. At the right of the receiver are a plurality of 
light-emitting diodes 142, indicating whether the incoming signal 
constitutes an alarm, listen, trouble, restoral, opening, or closing 
report. The received information is permanently applied to an associated 
printer 144 that supplies a tape 146 which records the date, time, the 
line, the account, the nature of the report, and its zone location. Thus a 
permanent and easy-to-read record is provided. By way of example, 
sequential entries as listed may appear on the tape: 
______________________________________ 
81/18 13:85 L1 ACCT 739 ALARM ZONE 8 
81/18 13:84 L1 ACCT 739 TROUBLE ZONE 9 
81/18 13:84 L1 ACCT 739 TROUBLE REPORT 
81/18 12:56 L1 ACCT 739 RESTORAL ZONE 2 
81/18 12:56 L1 ACCT 739 RESTORAL REPORT 
81/18 12:55 L1 ACCT 739 OPENING REPORT 
81/18 12:54 L1 ACCT 739 RESTORAL ZONE 5 
81/18 12:54 ACCT 739 RESTORAL REPORT 
81/18 12:51 L1 ACCT 195 ALARM ZONE 1 
______________________________________ 
Centrally on the front panel of the receiver are a plurality of 
light-emitting diodes 148 in a row-column arrangement indicative of the 
status of the four incoming lines. More particularly, the diodes indicate 
for each line whether it has a trouble, on-line or listen-in status. The 
line trouble diode will be activated if the phone line continuity is lost, 
and will energize the printer, print out the line trouble and line number. 
Each on-line diode will flash when a call is being received, and the diode 
thereunder will indicate which line is connected to the receiver speaker 
150, located physically to the left of the receiver. 
A volume control 152 for the speaker 150 is located therebelow, as well as 
a jack 154, allowing connection of an external headset. If one of the 
previously mentioned listen-in subscriber communicator units 10 is 
transmitting, the audio output will be heard. 
Additionally, below each of the line indicators, a push button 156 exists, 
and if depressed will transfer the call to the speaker 150, or if the line 
is inactive, depression of one button 156 will activate that line, 
bringing up the dial tone from the exchange and routing it to the speaker 
150. 
A manual "Print" button or key 158 on the receiver 16 can be depressed to 
test the printer 144 by printing the date and time. In turn, a "Silence" 
button 160 silences a buzzer 162 (not shown) which is activated when a 
report is received, and if depressed a second time, the "Silence" button 
will bring forth any additional received information or clear the visual 
display and permit the processing of other incoming information. 
If paper in the printer needs replacement, an ON-OFF switch 164 can be 
temporarily moved to its "OFF" position to allow such replacement. 
Electrically, the unit is arranged as shown in block diagram in FIG. 6. The 
receiver 16 is capable of receiving up to four different line cards 166, 
each of which includes an electronic interface port indicated at 168 
through which communication is established between the communicator 10 and 
the appropriate elements of the central receiver. More particularly, each 
line card 166 is arranged to direct the appropriate incoming audio signals 
to an audio frequency amplifier 170, which in turn delivers the audio 
message to the described speaker 150. While providing isolation of the 
adjacent circuitry from the incoming telephone line L1, the line cards 166 
are arranged electrically to direct the incoming signals to a tone 
receiver 174 which amplifies, filters, and digitally detects those signals 
received from the communicator unit and converts those tone bursts to 
binary signals for delivery to a processor unit generally indicated at 
176. Each line card 166 also includes a tone sender 178 which accepts a 
continuous square wave signal from a frequency divider 180 connected to a 
crystal oscillator 182 for gated delivery to the phone line L1 and 
ultimately to the communicator unit 10 under control of the processor 176. 
Low pass filtering is incorporated in the tone sender 178 to modify the 
square wave signal into an approximation of a sine wave output signal. The 
processor unit includes an input and output section 181 which receives 
information from and supplies control signals to each of the line cards 
166. Each of the line cards 166 communicates the following input 
information at appropriate times: ring down, presence of the incoming tone 
burst, failure of the incoming central office battery; and each line card, 
in turn, receives and transmits an off hook signal, a tone burst for 
delivery to the communicator unit 10, and a listen state which connects 
the incoming audio signals to the previously described amplifier 170 and 
the speaker 150. The previously described front panel switches, generally 
indicated at 182 in FIG. 6, are connected to a control input section 184 
of the processor to set the clock and calendar, select fully automatic 
printing or manual operation, provide for test printing, audible signal 
silence in the particular operating mode, as previously mentioned. It also 
contains an output control section 186 that delivers incoming signals both 
to the visual display 140 and also to a control electronics unit 187, 
arranged to energize the printer 144 for printing the received 
information. The output of the control section 186 also activates an 
audible signal unit 188 when a print request has been issued or the visual 
display unit 140 has been active for 20 seconds. 
The processor also contains a read-only memory section 190 which contains 
the general program and a random access memory section 192 which stores 
incoming information for display and printing, clock and calendar, and 
provides subroutine stack for storage of information generated by the 
processor. 
The central receiver is generally powered from a 110 volt AC line which is 
connected to a 12 volt transformer 194 and a voltage regulator 196 to 
supply suitable DC voltage for powering of the unit. A standby battery 198 
is connected into the system to supply temporary power therefor in the 
event of line failure, and a low battery sensor 200 will energize the 
audible signal 188 if the battery voltage approaches a critical low level. 
The described crystal oscillator 182 also, through the frequency divider 
180, is arranged to deliver eight millisecond pulses to the processor unit 
for timing the received tone bursts, and also supplies one-second pulses 
for the clock calendar functions. 
In summary, the central receiver enables visual display as well as a 
permanent record of any alarm, trouble, restoral, opening or closing 
reports from a number of the local communicator units in a rapid and 
effective fashion so that appropriate corrective action can be taken. 
As previously mentioned, while the type of communication using existing 
dial telephone circuits is extremely economical, in the event that a 
telephone line is cut, it would be impossible to transmit the information 
to the central receiving station, and as a consequence, in accordance with 
an additional aspect of the present invention, the mentioned separate 
multiplex transmitter 11 is arranged for connection to the digital 
communicator 10 so that information can be transmitted through a separate 
private line L2 running to the separate receiver 15 so as to indicate not 
only the report of an alarm condition but an immediate indication that a 
trouble situation exists, such as a break in the connecting line due to a 
phone company problem, equipment trouble, or a line compromise attempt. 
More particularly, the local multiplex transmitter 11, as shown in FIG. 7, 
is arranged for plug-in connection to the previously described digital 
communicator 10 after the programming unit 20 has been removed from such 
connection, and essentially is arranged to provide for generation of a 
normal supervisory tone at a particular frequency when normal operation 
exists. In the event that the supervisory tone is missing, the operator at 
a central receiving station to be described hereinafter will know there 
has been a break in this line. On the other hand, when an alarm condition 
exists, the frequency or tone will change to a new and unique frequency 
for that particular subscriber, and at the receiving end the change in 
tone will alert the operator that there is indeed an alarm condition 
present. 
With particular reference to FIG. 7, when this accessory multiplex 
transmitter 11 is connected to the communicator unit 10, a predetermined 
frequency (e.g. 2.09 MHz clock frequency) is delivered to the connected 
transmitter 11 and is first divided by a fixed factor of four by a 
conventional frequency divider 202. This divided frequency is further 
divided by a programmed binary-coded decimal divider 204 in a fashion to 
be described hereinafter, in a range that varies from a division factor of 
51 to a division factor 99. After such frequency division, a further 
division by a factor of four at a fixed divider 206 of the frequency 
routes the signal through a low pass filter 208 and then through an output 
transformer 210 to the private line L2 previously mentioned. 
Under normal conditions, the division factor of 51 produces a 2570 Hz tone 
which is the normal supervisory tone for the lowest number to count, and 
will indicate that normal operation of that communicator unit exists. 
Generally, if an alarm condition occurs at the local residence or other 
installation point, the unit is arranged to change the division factor in 
the programmed divider 204 to 52, thus decreasing the frequency which will 
change the frequency received at a central location and indicate the alarm 
condition, again as will be explained in detail hereinafter. 
To control the frequency division in the programmable divider 204, input 
data from the communicator unit 10 is delivered to a data latch 212 
providing eight lines 214 which differentiate between the alarm and normal 
condition. One line 214 is routed through a hold-in circuit 218 that 
causes the frequency shift to persist for a certain amount of time (e.g. 
one minute) to assure that the alarm signal is detected by the receiver. 
A failure detector 220 is also connected between the communicator unit 10 
and the data latch 212 so as to apply a reset signal to the data latch 
212, driving its output lines to all zero condition, resulting in no 
output signal, and the failure detector is arranged to produce this reset 
signal if either of two conditions occurs: (1) if a reset signal from the 
communicator unit comes into the failure detector, or (2) if the multiplex 
address line remains stable in any state for over one second. At the 
receiving end, this would be interpreted as a failure of the communicator 
unit 10 and, in effect, reports a trouble signal to the multiplex receiver 
15. 
It may be mentioned that the multiplex transmitter 11 draws its power 
connections from the main communicator unit 10 so as to require no 
separate power source. 
The multiplex receiver 15 which is illustrated in block diagram in FIG. 8 
is arranged to receive signals from up to 24 different transmitters 11 of 
the type just described, and to produce a display on a light matrix 
display unit 222 which represents the information carried by the input 
signals. More particularly, the display unit 222 includes, in this 
instance, 24 light emitting diodes arranged in three rows and eight 
columns, which will indicate the status of any of the particular 
transmitters providing input signals to this multiplex receiver. 
Incoming signals from all receivers are delivered to a coupling transformer 
224 that provides high voltage isolation and lateral balance from the 
incoming telephone line, and delivers each signal to a low pass filter 226 
at 2600 Hz to filter out any high frequency noise or signal harmonics 
which could interfere with proper signal detection. Each signal from the 
filter 226 is delivered to a phase-splitter 228 which provides two equal 
and opposite outputs (180.degree. out of phase) for delivery to detectors 
230, 232 connected in parallel for combination with two local oscillator 
signals to provide, in a conventional fashion, outputs consisting of the 
sum and difference products between the frequency of the local oscillators 
and the incoming signals. 
The local oscillator signal is derived from a 2.09 MHz clock 234 forming 
part of a signal processor 236. This signal is first divided by four in a 
pre-scaler 238 and then is further divided by a factor between 51 and 99 
in a programmable divider 240. This division factor is determined by the 
processor 236 to allow it to "tune in" on different frequencies in the 
composite received signal. In other words, the processor 236 programs the 
divider 240 so that it scans the entire frequency band of the 24 incoming 
signals. The local oscillator signal is next further divided by four in a 
digital phase shifter 242 in such a manner as to produce two outputs 90 
degrees apart in phase (in quadrature). One output goes to each detector 
230, 232. 
The two detector outputs are delivered to low pass filters 244, 246 with a 
cutoff frequency of 4 Hz, and provide an output which, if zero at one of 
the channels, would be maximum at the other, so that the incoming signals 
would be detected regardless of any incoming phase relationship. Signals 
from these low pass filters 244, 246 are delivered to voltage comparators 
248, 250, 252, 254 which compare the output voltage with that from a 
standard voltage reference 256. Ultimately, if no incoming signal is 
present which is within 4 Hz of the local oscillator signals, the outputs 
of both the in phase and quadrature low pass filters 244, 246 will average 
to zero and none of the voltage comparators will produce a voltage 
presence output. If, however, an incoming signal lies within plus or minus 
4 Hz of the local oscillator signals, this difference frequency component 
will pass through the low pass filters and one of the voltage comparators 
will produce a presence output so as to be delivered to the processor 236 
and ultimately displayed by the light emitting diode representative of the 
particular channel signal. 
As has been previously indicated, the redundant accessory system just 
described is of particular value to indicate an interference with the 
integrity of the main system, and can be particularly useful in 
combination therewith. However, it is to be understood, as previously 
mentioned, that it can be used separately as an indicator of conditions 
resultant from certain alarm trouble or system restoral operations, and 
moreover can be utilized with the central station receiver previously 
described and utilized with the communicator unit itself. 
The communicator unit 10 can, of course, be used with other central 
receivers with appropriate programming, and thus can be added to existing 
systems as a replacement for the local alarm unit to achieve its inherent 
advantages. 
These and other variations and/or alterations as described can be 
envisioned within the general spirit of the invention, and accordingly the 
foregoing description of one system and accessories thereto is to be 
considered as purely exemplary and not in a limiting sense, and the actual 
scope of the invention is to be indicated only by reference to the 
appended claims.