[Milsurplus] RU-16/CW46051A

[Hue Miller]

I do not have an RU schematic around here at present, but i would think 
that you could dispense with the AGC feature and its required high negative
voltage, and just rely on the manual RF gain via the control box. However, the
main problem, unless you are only going to use it on the AM-broadcast band,
is selectivity - the thing being TRF, is actually unusable on HF. Imagine trying
to separate SW broadcast stations near 10 MHz with 3 tuned stages of HF
selectivity! I am thinking the only way to actually use the receiver on HF in 
AM/ A3 mode is to build in a 2-terminal Q-multiplier using FETs, on the first
tuned circuit, and control it via a separate pot outside the radio in its own little
additional "control box".  Regenerative RF stages themselves - i mean like
providing feedback in one of the 39/44 amplifiers itself - doesn't work all that
comfortable because the gain varies so much with the selectivity adjustment.
Apparently as a direct-conversion receiver on CW the RU does function well
enuff, anyway so i was told by a ham fellow up in Seattle who actually used one
in the PBY.  He was a post-war radio op, but flew PBYs being ferried over to
the Philippines where they were donated to the Filipino military. Altho post-war
the PBYs still had the RU - GO-9 setup. Whereas at least some PBYs doing
anti-submarine patrols off the USA and perhaps? all other PBYs on Pacific
War combat duty had been changed out to BC-348 / ART-13.  -Hue Miller