MORE TRC-77 INFO;
Ed) The below is a response sent to Tony Grogan from Tom Babb as a result
of his inquiry stemming from my statements on the TRC-77/LRRP use in the
Tony, I will address the above questions as
well as I can. The original design was from Fort Monmoth and the first
contractor was Sylvania The second and only other contracts were
made by Arvin Military Systems Division in Columbia Indiana.I was
a young technican at Arvin in the middle sixties. I worked on the
contract prototype and contract acceptance units which had to go
to Ft Monmoth for final acceptance. This is when the engineers said
that they saw the original unit that was built by the Signal Corp
engineers and turned into the TRC-77 as we knew it in the Slyvania
design. The TRC-77 was indeed built to xmit at 300 wpm. There is a
special keyer board to make this possible. During the final testing
of the TRC-77 we used a square wave generator to key the transmitter,
looked at the output on a scope and had to put a
picture of the high speed keying trace in the final test book for the sig corps. As a side note, this was one of the last contracts that we dealt directly with the signal corps. Sometime after we started dealing with the DECS which if memory serves me right stood for the Defence Electronic contracts services. My memory is a bit
foggy after fourty years, but I think that is what it stood for.
During this same time we also were building
the GRA-71. My main envolvement was primarily with the cordwood modules
that were used in the GRA-71.Talk about a bear to build and then
repair, I think this was when I started my gray hair. We did indeed
use the TRC-77 as a test bed to test out the GRA-71 in the same manner
as we tested the TRC-77 and this was to use the GRA-71 to drive the
TRC-77 and take a photo with a scope camera of the keying wave shape
of the output of the TRC-77 at 300 wpm.
As to the cable pin outs that was to be used with the GRA-71, I cannot remember, but the cable that we shipped with the units is in the bag of accessories that you got from me.
As a final note the TRC-77 was capabale of cw transmisson only but did have am recieve capabilities and I can assure you that It was meant to be used with the GRA-71. I hope that this has been of some help
Tom Babb kk4bu
Ed) While the above information does not add much weight to the TRC-77/LRRP
use/question, it does give us some new information & valuable insight
into the origins of the TRC-77.
The first is the statement that the TRC-77 was originally designed by the Signal Corps themselves(though it would not have been the last such project as the PRR-9/PRT-4 dates several years later than the TRC-77).
Second, the Signal Corps was restructured(ceased to exist as a separate entity) in 1962 and in effect became just another department of the Army. I/E their work on the TRC-77 would have been taking place before this date(as noted by Mr Babb with their subsequent dealings with the DECS). On a side note, the RS-1 was adopted by the army as the GRC-109 at almost the exact same time. Also, the first official manuals for the TRC-77 were printed in 1962.
As noted in TM11-5820-47312(1965) & with Mr Babb's testimony above, the TRC-77 was indeed capable of operation with code burst keying(using special purpose cable CX-11389/TRC-77A).
Though the use of the TRC-77 by Army LRRP's is still in question, this radio would have represented a fairly attractive package to those tasked with it's carry & use(when compared to the only other radio in existence as of 1962, the GRC-109). But by 1965 and the entrance into the battlefield of the PRC-64 & PRC-74, any advantage to the TRC-77 would have very quickly faded.
For more information on the above subjects see the below:
MCGP Backmail #29;
TRC-77,Good Radio,Wrong Time. by Dennis Starks
ANOTHER CLUE TO THE TRC-77's USE; From Steve Hill
MCGP Backmail #43:
GRC-109/RS-1; What, Why, When, Where
Part I, An Interveiw With Bob Olsen,
by Pete McCollum
Part II, Descriptions, & Observations of the RS-1,
GRC-109, & GRA-71 By Pete McCollum
with Further Comments by Dennis Starks
Part's III, History ? by Pete McCollum
Dispelling The Myths, Part I, by Dennis Starks
Part IV; Dispelling The Myths, Part II, by Dennis Starks
Part V; Dispelling The Myths, Part III, by Dennis Starks
RS-1/RS-6/GRC-109; Serial Number Info, By Pete McCollum
additional data on the all the above & similar topics may be seen on Pete McCullum's we site at:
MCGP Backmail #58,
DATING EQUIPMENT; Input From Tom Norris, & Pete McCollum.
(RS-1, GRC-109 Examples)
Dennis Starks; Collector/Historian
Midwest Military Communications Museum
Cross Timbers Mo.
Editor & Sponsor of the "Military Collector Group Post"
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