[Milsurplus] U.S. Army TRF LF receiver 1934

[Kenneth G. Gordon]

On 10 Nov 2015 at 9:28, C.Whitaker wrote:

> de WB2CPN
> TRF receivers did not have a local oscillator, and were avoided
> where the LO could be picked up.  Such as Navy at sea.
> WWII trivia, but factual.
> 73  Clete

Not completely true: the RAK/RAL were TRF and used extensively by the 
Navy all during WWII. The RBL was a TRF also, and I am sure there were 
others. One of my RALs had been the main HF receiver for the USS Pintado 
a fleet sub.

The Navy specified a very low radiation level at the antenna, something like 
a few micro-micro-watts of radiation at the antenna connection, and the 
TRFs that the Navy used all met that specification.

National had to add a second RF amp stage to one of their superhets before 
the Navy would accept it for use on ships.

In fact, from my reading, many of the old Navy radio ops preferred the 
RAK/RAL over the newer RBB/RBC since they insisted that the earlier 
receivers were less susceptible to overload by nearby transmitters due to 
their more extensive shielding.

Ken W7EKB