[Milsurplus] Re: Beginning of use of UHF aero radios

[gfdubois at juno.com]

> Does anyone know the aprox year that UHF (225-400) was adopted for
military

In Docket 6651 (1945), the FCC still had three proposals for the "lower"
frequencies, including the FM Broadcast band at 50 to 68 MC. But the band
225 - 328.6 and 335.4 - 400 MC was allocated for Fixed and Mobile
service, with the US allocation showing "Government (military) with
adequate channels to be reserved for civil aviation."  In a follow-up
Order in the same docket, the US allocation was listed as "Government, 75
Aero channels for Non-Gov."  
Well, that part never happened, did it?


> The AN/ GRC-27 ground station - 100 watts uhf  which  I have here,
> shows its manual to be April 1951. The R-278 rx  is  S/N 8. and works
fine..

>  The RAAF pensioned these off some time back but only went to the
> crusher a  couple of years back. claim apparently to let  them loose
> was not in the  national interest.


Even though you can buy scanners that cover that same band??

The R-278 is a neat old receiver. A mechanical marvel, but a bitch to
align. 
Standard installation was one multi-channel GRC-27 for every four
GRR-7/GRT-3's in an Air/Ground site. There were also usually one or two
in the control tower for a local backup.

S/N 8 ???
Mine are Delco - s/n 1045 and 2147. One came from PDX, the other a 25th
AD RCO.

I'm going to fire up one of them again here one of these days, to use
with the CRD-6 I've been sitting on for ten or fifteen years. 
Course, I can always use my AOR 5000, since the AGC can be turned off in
the 5K - a requirement for the CRD-6 (and the reason for the AVC switch
behind the lower front cover on the R-278).


> I have a complete system that was Collins built that was obtained in
about 1990 unused never fielded

Wow!
How'd you come by that?


George