Technical Radio Corp T-350XM xmtr???

[W6SSP]

Picked up one of these monsters last year. Hoping to find someone
else that has one to compare notes during restoration. I'd also
like to find out something about this company (located in
San Francisco). Have found nothing so far. I do have a manual
in case someone needs a copy.

A few details; The T-350XM is an AM/CW transmitter covering
2-20 MC using either crystals or a master oscillator. Final
amp uses two 813's and modulator uses a pair of 805's.
350 watts CW, 275 watts AM. Weighs 690 pounds, about
5 feet tall. Appears to be WWII vintage but is not military.
Steve

[WA7KKP]

Never heard of this particular model -- I was thinking it was the SSB exciter with the 2-4cx250's PA deck . . .

TMC did build mil-spec gear, but this one sounds like a commercial replacement for the venerable BC-610. The nice thing about TMC is that the build quality is impeccable -- IMHO even better than Collins. I consider the TMC GPR-90 a well-built Hammarlund . . . I'd like to own a GPT-750, with both the SSB exciter and modulator decks, so I could do high-level modulated AM. Only seen one of them though.

Gary WA7KKP

[W6SSP]

Hi Gary,
This transmitter is made by the Technical RADIO Corp, not
the Technical Materials Corp (TMC). Thats why I' having such
a difficult getting any info about the transmitter or the company.
I did see a receiver made by TRC on fleabay a while ago but
thats it. Here's a link to one that lives in France. Its identical
to mine except it used 814's for the modulator;

www.qsl.net/f5maf/f6hsba.htm (http://www.qsl.net/f5maf/f6hsba.htm)

Steve

[W5HTW]

Never heard of this particular model -- I was thinking it was the SSB exciter with the 2-4cx250's PA deck . . .

TMC did build mil-spec gear, but this one sounds like a commercial replacement for the venerable BC-610. The nice thing about TMC is that the build quality is impeccable -- IMHO even better than Collins. I consider the TMC GPR-90 a well-built Hammarlund . . . I'd like to own a GPT-750, with both the SSB exciter and modulator decks, so I could do high-level modulated AM. Only seen one of them though.

Gary WA7KKP

Yeah I read what I thought I was reading, rather than what I was reading! I thought it was a TMC PAL-350. Which was a very nice table-top rack 350 watt amplifier.

Never heard of the Technical Radio Corp here, either. That sounds like a very healthy transmitter, perhaps a mil-spec unit to compete with the T368. Power output, though, as you mention, is similar to the BC610 series. So is weight, actually, though the T368 is no lightweight!

I had opportunity to use a GPT750 many times, in various configurations, and a few hams have them. They are not really frequency agile, but are built to last forever plus 500 years. We used them mostly with the SBE exciter module, for AFSK.

I'm out of "big" so this T350 would not be something I'd want on my bookshelf. But I bet it would be fun to play with!

Ed

[KD2WW]

Steve,
I just completed a restoration of a T-350XM sn 593 and am working on another sn 600. Both have contract numbers and Signal Corps. acceptance stamps so I assume they are military units. The two transmitters were disassembled when I received them and incomplete. Someone removed the 805's and 813's along with the speech amplifiers and a modulation transformer. They were probably idle for a couple decades.
I found an operating manual on ebay that had enough info to get 593 operational. The biggest problem I found was most of the wirewound resistors were open. I had to fabricate some different mounts for the replacement resistors and replace some paper capacitors . That was followed by a general clean up and lubrication of the various gears , counters and switches. I did not have the proper speech amplifier so I substituted a Bogen C20B PA amplifier along with an EV 638 microphone. Reports indicate excellent audio and the internal VFO seems to be quite stable. I run the line voltage a bit on the low side and get 275w out on 75 meters. 73, Merrill KD2WW

[W6SSP]

Merrill,
Glad to hear there are some of these out there being restored!
I sent you a private e-mail but got a wierd error message. If
you don't get it, could you contact me at zarco at sonic dot net?
Thanks!
Steve