[Milsurplus] Power Supply Requirments for the RBM HF Receiver

[WA5CAB--- via Milsurplus]

Terry,

Besides the 11 tube filaments @ 150 mA there are also two dial lamps.  I 
didn't look them up but certainly no more than 150 mA.  So 2 A @ 12.6 V is 
still adequate.

The odds of ID-ing the RBM model number  are fairly slim.  There were six 
"models" (RBM through RBM-5) but the Navy SOP was that additional orders 
usually got the model number incremented.  Externally, RBM through RBM-4 look 
the same.  The HF receivers are all NT-46077.and all have a small box on front 
with a calibration roll chart inside.  Some were made by Westinghouse (CAY) 
and some by Stromberg-Carlson (CCT).  The RBM-5 HF receiver is CAY-46077A 
and has a thinner box with calibration cards.  So the cal chart or cards 
(assuming someone didn't remove them) would determine RBM-5 or RBM through 
RBM-4.  There were a few minor circuit changes to reduce RF oscillator radiation 
but as they were supposed to have been made to all sets RBM through RBM-3 
and were standard on RBM-4 probably wouldn't help any.  The only way to 
possibly pin it down a little closer would be if you can find evidence inside as 
to whether the receiver was built by CAY or CCT.

I do sell a reprint of the final NAVSHIPS manual if you decide that you 
need it.

Robert Downs - Houston
wa5cab dot com (Web Store)
MVPA 9480

 
> On Tue, Aug 19, 2014 at 3:15 PM, T. Comstock via Milsurplus <
> milsurplus at mailman.qth.net> wrote:
> 
> >I picked up what I believe is a RBM HF Receiver this past weekend, 
> someone
> >along the way removed the nameplate
> >and installed a meter.  Because the knobs don’t include the large 
> letters,
> >I believe that I have a RBM unit, is there a
> >way to tell which flavor or model I ended up with?
> >
> >Using the info from the RBS documentation found on line (no luck with 
> more
> >than a schematic for the RBM), I found
> >the power connector pin out and the need for 12.5V and 215V but not sure
> >on the current requirements for
> >both voltages.
> >
> >Any help would be appreciated, and if someone might know where I can find
> >a nameplate when I make an effort to
> >attempt a restoration (there is a fear that the hole is too large to 
> cover
> >with the original nameplate).
> >
> >Thanks,
> >Terry
> >W7CJ