From: estey@skyler.mavd.honeywell.com
Subject: ARRL DIGITAL COMMITTE REVISED REPORT 9/26/92
Organization: Honeywell Systems & Research Center
Date: Fri, 9 Oct 1992 17:37:42 GMT


                        Report and Recommendation 
                 to the ARRL Board of Directors, from the 
        ARRL Committee on Amateur Radio Digital Communications
                            September 26, 1992
 
     At the request of the ARRL Board of Directors, the ARRL Digital 
Committee met today with five elected representatives from the group of 
amateurs operating automatic HF message forwarding stations under 
FCC Special Temporary Authority originally dated July 7, 1987. What 
follows supersedes and replaces the Committee's June 13 report.   
 
     Additional data, not available at the time of the Committee's June 13 
meeting, included:
 
A.      Revised IARU Region 2 band plan resulting from the September 
        4, 1992 meeting in Curacao.
 
B.      Additional feedback from amateurs at large, and the STA 
        community, received since the June 13 meeting.
 
     The committee is revising its previous recommendation to include 
fully-automatic, unattended operation on the IARU "packet priority" sub-
bands and semiautomatic operation in all digital sub-bands.
 
IARU Band Plan
 
     The Digital Committee, at its June 13 meeting, was concerned 
about frequency usage and allocation in the US. and other countries, in 
effect at that time.
 
     The September 4, 1992 IARU Region 2 meeting in Curacao 
produced a substantially revised band plan for digital modes.  The new 
plan includes segments on all amateur bands between 80 and 10 meters 
for "digital modes," defined as including RTTY, AMTOR and packet 
(including new systems like PACTOR and CLOVER), but not FAX and 
SSTV.  Within those segments, "packet priority" sub-bands were defined 
(except on 40 meters) in which digital modes other than packet are 
permitted, but may not claim protection from packet.  It was agreed that 
CW remains a permitted mode throughout all amateur bands.
 
     The Digital Committee and STA representatives believe strongly 
that no distinction should be drawn -- in terms of spectrum usage -- 
between digital modes.  Technology development is advancing quickly.  
Any mode could be outdated and replaced with better, more efficient 
technologies at any time.  Mode-specific plans will limit spectrum for 
development, and may reserve spectrum for modes soon to be obsolete.  
     
     For that reason, and in light of what follows, the Committee prefers the 
term, "automatic priority," instead of the IARU's term, "packet priority."
The Committee believes the following recommendations will better 
align the US. band plan to the IARU Region 2 agreement.
 
Additional Feedback Received
 
     There is reason to believe that many  VHF and UHF operators 
overlooked the QST survey, assuming a "below 50 MHz" issue had little 
effect on them.  The impact on message traffic between widely separated 
VHF and UHF packet bulletin boards was not immediately understood.  
 
     As mentioned in the Committee's June 13 report, every Committee 
member read every written comment submitted by the respondents. 
Those comments emphasized areas of great concern by many amateurs, 
and significantly influenced the Committee's previous recommendation.  
The concerns remain quite valid.  The Committee believes new means are 
now available to address them, while, at the same time, enabling 
additional activities and developments that will benefit amateurs and the 
public interest.
 
     A primary concern, among many amateurs is interference to 
stations under human control by stations under computer control. 
Except for a very few special situations, by tradition (and rule), one 
amateur station must not willingly or knowingly interfere with a contact 
already in progress, regardless of mode or the perceived importance of 
the communication in progress. 
 
     Semiautomatic operation has been defined by the Committee as 
requiring a local control operator at the calling station, to guard against 
interference to existing communications.  The station being called 
operates automatically, but on a "speak only when spoken to" basis.  
Semiautomatic operation received a 2:1 majority (those favoring vs. those 
opposed) in the QST survey.  The Committee interprets that response as 
a strong vote in favor of automated message handling, provided it can be 
a "good neighbor" to other spectrum users.  
 
     Initial survey respondents, while not favoring automatic operation, 
said (if automatic operation is permitted) they preferred sub-bands by a 
4:1 ratio over any other proposed scheme.  They did not favor the idea of 
exclusive sub-bands for specific modes.
 
     The STA participants point to their commendable record in creating 
a nationwide network for moving hundreds of thousands of messages 
efficiently and without technical difficulties. Their efforts have lived up to 
Part 97.1 (a), Basis and Purpose of the Amateur Service, "Recognition 
and enhancement of the value of the amateur service to the public as a 
voluntary noncommercial communications service, particularly with 
respect to providing emergency communications."  
 
      Countless pieces of traffic have been transported in national and 
worldwide emergency situations.  Messages of a "hobby" nature have 
been an important vehicle allowing the network to be developed and 
maintained in a state of readiness. 
 
     The technical effort required to construct this network, both in 
hardware and software technology has been considerable, and certainly 
meets 97.1(b), "Continuation and extension of the amateur's proven 
ability to contribute to the advancement of the radio art."  
 
     Thousands of bulletin board operators (sysops) and tens or 
hundreds of thousands of digital operators have learned to originate, 
relay and deliver message traffic by means not previously available.  Part 
97.1(d), "Expansion of the existing reservoir within the amateur radio 
service of trained operators, technicians and electronics experts," has 
also been served.
 
     There is no question of the value provided by this message network 
to other amateurs and to the public at large. The Committee 
acknowledges the success, both technically and functionally, of the STA 
experiment.  There have been a few reports of interference to foreign 
phone stations where international band plans conflict.  There are few if 
any reports of problems with other US stations.  The IARU accord 
minimizes or eliminates the concern for interference to foreign stations.
 
     A major concern had remained, however, that unrestricted HF 
automatic operation permitted to all General, Advanced or Amateur Extra 
class licensees, could easily result in interference to other stations on a 
completely unacceptable level. Subdivision of bands by rule was 
previously rejected, in part because, "it will not work on a world wide 
basis because of the differences in the rules between regions and 
between individual administrations."  The IARU has now provided a 
subdivision plan which has already met with international approval.
 
 
 
RECOMMENDATIONS
 
I.      The Committee wishes to enable as many amateur licensees as 
possible to contribute to, and enjoy, our service. The previous 
recommendation stands, to permit semiautomatic operation in any 
digital portion of any band.  This privilege will permit a variety of 
experimentation and operations such as personal mailboxes and 
MSOs to co-exist with "live" users, on a non-interference basis.
 
II.     By using the IARU Region 2 band plan, US operation will be in 
compliance with international agreement.  Since the sub-bands 
designated by the IARU as "packet priority" will offer no protection 
from interference to other users of that space, including US 
amateurs, the Committee proposes fully-automatic operation by US 
amateurs within those segments of the band, using any approved 
digital data mode.  It is recommended that those segments be 
dubbed "automatic priority," as a more accurate, descriptive term.
 
III     No packet priority segment was specified by the IARU on 40 
meters, yet automatic networks have been operating there since the 
beginning of the STA.  As we approach the sunspot minimum, and 
the MUF lowers, 40 meters will be badly needed for many 
propagation paths.  The Committee therefor urges approval of a 
small automatic priority segment from 7.100  to 7.110 MHz.  
 
        Similarly, no digital segment was specified by the IARU for 160 
meters. While there is little or no digital activity on this band, 
developing modes show promise of improving operation in this 
somewhat hostile (digitally) environment.  The Committee feels it 
would be a valuable testing ground, and requests an automatic 
priority segment from 1810 to 1820 KHz.  Specific frequencies 
recommended for automatic priority are listed in Appendix B
 
IV.     The Committee cannot overemphasize our concern for protecting    
other spectrum users from the potential interference of automatic    
stations.  To this end, the recommendation for automatic operation 
is made on the basis that protection by rule will be provided in the 
form of specific sub-bands to which fully automatic operation is 
restricted.  
 
        There is precedent for special use, by-rule sub-bands, as in 
97.203(d) for beacon stations.  Any other usage plans, within digital 
segments, should be by voluntary plan, not by rule.
 
        The requested sub-bands should not place an additional 
enforcement burden on the FCC.  Amateurs have always been 
largely self-regulating.  The committee views the requested rules not 
as something else the FCC must spend time monitoring, but rather 
tools to enforce reported infractions. 
 
V.      By current standards, AX.25 is considered the least efficient protocol 
in use for digital modes.  The STA representatives request, and the 
Committee wholeheartedly agrees, that AX.25 protocol be struck 
from 97.109(e) as a requirement, and replaced with the ability to use 
any accepted digital protocol.  
 
        Because the investment in technology development is large, 
developers hesitate to widely publish details (competitive 
disadvantage) in the early stages.  To address this issue, it is 
proposed that developers be allowed the latitude to use new 
protocols, during the development phases, so long as they file details 
of the protocol, privately, with the ARRL.
 
VI.     Because digital technologies are developing rapidly, the Committee 
proposes to compile, and provide to the Board, a proposal for any 
desirable adjustments to Region 2 band planning, prior to future 
IARU Region 2 conferences.  
 
VII.    The Committee reinforces its previous suggestion that the League 
undertake publication of a tutorial-style operator's guide for HF 
digital operations clearly defining acceptable operating practices, 
voluntary-use band plans, DX windows and beacon frequencies.
 
 
 
 
 
 
                          Appendix A
 
 
     The following is suggested wording for an addition to Part 97 
authorizing automatic and semiautomatic digital mode operation.  Note 
that RTTY, AMTOR, packet, CLOVER, PACTOR and future digital data 
modes are treated equally as "digital modes."
 
97.3  Definitions
 
( ) Unattended Digital Station - A station in the amateur service, using 
any accepted digital mode protocol for data or message transmission, 
and  operated without a local control operator present.
 
( ) Semiautomatic operation - A two-way communication in which the 
control operator of a locally controlled amateur station manually 
initiates, monitors and controls communication between that station and 
an unattended digital station.  
 
97.109 (e) No station may be automatically controlled while transmitting 
third-party communications, except a station retransmitting digital radio 
communications using an accepted protocol on the 6m and shorter 
wavelength bands, or on 10m and longer wavelength bands in sub-bands 
where automatic control is specifically authorized.  The retransmitted 
messages must originate at a station that is being locally or remotely 
controlled.
 
97.216 Unattended Digital Station
 
(a) Any amateur station licensed to a holder of a General, Advanced or 
Amateur Extra Class license may be an unattended digital station.
 
(b) An unattended digital station may operate on any frequency 
authorized for digital transmission modes.
  
(c) No unattended digital station may initiate contact with
another station or broadcast any undirected signal unless operating in a 
band or band segment where fully-automatic operation is authorized. 
 
(d) The transmitter of an unattended digital station must be equipped 
with a functioning time-out timer that will insure no signal is transmitted 
for longer than five minutes in the event of the malfunction of control 
equipment or loss of contact with another station.
 
(e) Unless operating in a band segment where fully-automatic operation 
is authorized, the control operator initiating contact with an unattended 
digital station must be present at the local control point.  The control 
operator must first ascertain that no interference will be caused to 
existing communications, must remain present for the duration of the 
contact, and must discontinue the contact if it becomes evident that 
communications with the unattended digital station is interfering with 
other amateur communications.
 
 
 
 
 
 
 
                          Appendix B
 
     It is recommended that all stations under automatic control be 
restricted to the following Sub-bands...  
 
 
        10  M:  28.120  -       28.189  MHz
 
        12  M:  24.925  -       24.930  MHz
 
        15  M:  21.090  -       21.125  MHz
 
        17  M:  18.105  -       18.110  MHz
 
        20  M:  14.095  -       14.0995 MHz
                14.1005 -       14.112  MHz
 
        30  M:  10.140  -       10.150  MHz
 
        40  M:  7.100   -       7.110   MHz
        80  M:  3.620   -       3.635   MHz
 
        160M:   1.810   -       1.820   MH
                                 
                                 ###
 
______________________________________________________________________________
Carl Estey                  |  Home Mail Address: 276 Walnut Lane
Amateur Callsign:    WA0CQG |                     Apple Valley, MN 55124
                            |  Business Address:  Honeywell Inc.
Phone: Work (612) 542-5136  |  Flight Systems & Test Operations M/S MN15-2370
       FAX  (612) 542-6003  |  1625 Zarthan Ave. S., St. Louis Park, MN 55416
       Home (612) 432-0699  |  Packet: WA0CQG @ WA0CQG.#SOMSP.MN.USA.NA   
The nonsense here is of my own making - no one else would want credit!