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

[Kenneth G. Gordon]

On 9 Nov 2015 at 13:36, jmfranke at cox.net wrote:

> The RBA does not have a regenerative detector. It has "a triode biased near
> cutoff with a large cathode resistor and uses plate rectification." Hence, there
> is no regeneration control.

True, but I understood it as a regenerative detector which has been fixed at a 
regeneration point just short of oscillation. In such a case, there would be no 
need, or desire, for a regeneration control.

Page 16 of the manual: "The detector is of the plate rectification type." Then 
goes on to describe the circuit in detail.

I have two RBAs, and an original manual, and that is what the manual 
"suggests" to me. I may be reading it differently, and maybe incorrectly, or 
my memory may be faulty (most likely) from you, but that is my 
understanding of it.

The RBA has several very interesting design features: one of which is that 
the third RF amp is set up as a limiter. Another is that the audio output stage 
is set up to be able to feed from "one to twenty 600 ohm" headphones with 
"less than 40% change" in audio level. 

20 headphones,...?????? Why?

Supposedly, the RBA is the "last word" in VLF TRF receivers. I 
dunno...maybe...it sure weighs enough...

Ken W7EKB