[Milsurplus] WWII receivers

[Al Klase]

OK, I'll weigh in on this one.

Super-Pro - RBB/RBC - AR-88:  These are all excellent receivers, and 
which is best is probably dependent upon the particular operating 
circumstances and personal preference.  Like Rob said, you'd have to sit 
down with the radios side-by-side with good antennas and test equipment 
to come to a really solid conclusion.

That said, these sets were designed in an era when the state of the art 
was advancing at a significant rate.  Clear improvements are evident 
when we examine the designs from the Super-Pro in 1935 through the 
RBB/RBC in about 1938 to the AR-88 in 1941.

For one thing, tube technology was marching forward.  The Super-Pro uses 
6K7's with a transconductance of 1700, the RBC uses mostly 6SK7's at 
2300 plus a hot 6AB7 (5000) "TV Pentode" in the 1st RF, while the AR-88 
used the latest 6SG7's throughout with a transconductance of 4700.  The 
higher values result in better noise figures, perhaps only significant 
at the higher frequencies.  There's also a clear progression in the 
mixers used.

Some shortcomings in the Hammarlund:  Separate band-spread control makes 
it difficult to return to a particular frequency.  Unsophisticated 
crystal filter.  Non-regulated power supply.  Not-so-great S-meter.  Is 
the LO temperature compensated?

RCA was the 700-pound gorilla of receiver (and vacuum tube) design, plus 
the RBB/RBC has a secret ingredient:  MONEY.  They cost something like 
two grand each.

The AR-88 enjoys the advantage of being the last to be designed, and it 
shows.  It's not so well know because the US military had already picked 
it's communications receivers and most of the production went to the 
Brits and Russians.  The bulk of the military general coverage 
short-wave receivers we did use were RCA designs or at least heavily RCA 
influenced:  RAB, RAL, RBB/RBC. BC-348, ARB, BC-312/342, etc.

I choose the AR-88,
Al

C.Whitaker wrote:
> de WB2CPN
> I thought the BC-779 was superior to the AR-88, and there were
> so many of them in service with Air Force fixed-plant.  The AR-88's
> did do 10 Mtrs.  It appears the BC-779 had a certain amount of
> permanency when the number of power supplies that were developed
> for it is considered.   And like some of the Navy equipment, the BC-779
> uses a terminal strip for conection to the power supply. 
> 73  Clete
>
>
>
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-- 
Al Klase - N3FRQ
Jersey City, NJ
http://www.skywaves.ar88.net/