[Milsurplus] Newly acquired RT-46/TRC-10

[Hubert Miller]

I like to think the set was used for what it was intended for, the Philippine coast-watchers and observers,
but…I have some Pilot Radio Co. docs from the same date as the manual, from a meeting with government
officials, where they were calling for several modifications to the design. One thing I thought was cute was
that one spec that was "failed" was the selectivity spec – the radio was more selective than the military
contract spec called for. In this particular item, the spec was relaxed and the tighter selectivity was accepted.
I assume the wider spec was called for, because unlike us on contest weekend, the mil operator might be
monitoring a frequency and either his or the distant equipment might be slightly off frequency, and you
wouldn't want him to miss a call. But this was already intro springtime 1945, when the Army was taking over
from the Navy in building networks in the Philippines and supplying them, and providing , mostly – I think –
BC-1306 radios for this use. So I don't know if this radio got off the ground, so to speak. I actually think the
trans-receivers with the 1.5 filamentary tubes were preferable for this mission type radio, as you could
monitor a frequency for a spell, using only battery power, while radios such as the TRC-10, PRC-1, and MBM
required an AC hookup, a heavy wetcell lead-acid battery, or someone sweating away at your handcrank generator.
For some reason, it seems some of them were given to C.A.P. units after the war, which is kind of odd, as C.A.P.
I think was using  only voice comms on MARS freqs above 80 meters. I base this on a photo in an old Radio News
and also a comment from an OT ham.
You'll notice that with the AC supply, the 2E22 has AC on the filament. I replaced this tube with an 807, just
changing the plate cap. If and when you get yours working, I'd like you to measure the receiver plate voltage.
On mine, this receiver voltage seemed insanely high. I have not gone farther to check actual set resistances
or see if it's a design flaw. That's kind of where I left it, some years back; no progress since then. I have the
antenna and the AC supply.
-Hue
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