[Milsurplus] is that an oscillator I hear whining?!

[William Donzelli]

> The URR-13 and URR-27 (UHF and VHF) were designed to minimize the radiation
> of RF from the LO.  These radios were extensively used on US submarines
> during and after WW II.

I do not think these were available until the late 1940s. For VHF on 
subs, I think they used AN/ARC-4s and SCR-624s. By 1950, however, the 
URRs were all over the place.

Speaking of which...

In the stack of '-13s, '-27s, and '-35s here, I have one oddball - a 
National set called AN/URR-28(XN-3). I suspect this was perhaps a 
competitor to the '-27, and lost the fight. I know this may be a long 
shot, but does anyone have any information about this set?

William Donzelli
aw288@osfn.org