I have what may be a few-of-a-kind (or one-of-a-kind) R-392 receiver.
Its 99% the same as a standard R-392 but has a Collins/Navy contract
number. Its s/n 2. The color is also the darker Marine Corps OD paint
and the front panel is held with twist-dogs instead of hex head screws.
The case appears a bit more massive that the others I have.. but same
overall size. Its all factory, though. The set works fine. I've never
heard of the Navy/USMC buying/using the GRC-19, but maybe they did. Or,
maybe they just bought receivers to replace the GRC-14? If anyone's has
add'l info and/or interested in the unit, please let me know. I already
have sufficient R-392's for my GRC-19 setups.
de K3HVG