[Milsurplus] Question

[howard holden]

The USS Ling SS-297 at the NJ Naval Museum in Hackensack NJ, where I did volunteer work for many years, has 2 RBS. It was originally outfitted with two of them although the two aboard are not the originals. Both have the power supply.

Not really wonderful receivers, and both had a weakness in which the springs on RF deck trimmer caps weakened or moved enough to short out the caps. Required "open heart" surgery to remove the three RF modules (RF, osc, and mixer) and effect repairs. The RAL, also standard on the Balao boats, was a far better receiver. But the RBS could be used in a pinch. Never could figure out why they were aboard. A single RAL as a spare would have made more sense.

Howie WB2AWQ

Sent from my iPhone

On Aug 22, 2016, at 11:32 PM, Hubert Miller <kargo_cult at msn.com<mailto:kargo_cult at msn.com>> wrote:


That's what immediately came to mind, and i believe i saw the same in Bowfin at Honolulu.
The RBS and practically identical RBM-hf   ( 46277 ) are neat looking and very nicely assembled, as they should be for the approx $1000 Uncle Sam paid for them.

The downside is the fast tuning rate and selectivity with the 1240 kHz IF. Selectivity is two step, wide and wider. Both tuning rate and selectivity are worse than

with the BC-348.

I think it's a shame the tuning rate is so high. I admire that use of a 6SJ7 mixer instead of the noisier 6SA7 that the BC-348 uses.

The selectivity can possibly be handled with a Q-mulitiplier, possibly using the dial dimmer light hole, altho once

you have played with the dial dimmer, it's a real fun accessory to have, and you can dial in just the most pleasing dial illumination.

I didn't know the "big power supply" with the audio amp in it is rare, but that may be true. I have seen two out here. I think when John Nelson and i shopped at the

ship conversion place at Lake Union, Seattle, i chose the small RBM supply and he took the big RBS supply. All the RBM/RBS/ and power supplies worked

perfectly, 50 years after their last use.

-H M



Sent: Monday, August 22, 2016 11:19 PM

Subject: Re: [Milsurplus] Question



Floyd,



Class 42 was not specified or used.  Most likely, the receiver was a CCT-46217, part of Model RBS and RBS-1.  Covers 2-20 MC A1/A2/A3.  In the photo, it should have been mounted vertically to a bulkhead in a CCT-10227 rack and cabinet, with a CCT-20235 or 20235-A Rectifier Power-Amplifier hanging from the bottom of the cabinet.  If it was a 10227-B, it should have been mounted on a shelf or open bench with CCT-20235-B hanging below.



Electrically and mechanically the same as CCT-46077 or 46077-A (HF receivers of RBM through RBM-5) except that four of the control knobs have large white-filled letters engraved on them.



Performance wise, it was pretty good for its day, roughly equivalent to BC-342 or BC-348 performance wise.  Two RF, two IF, AVC, ANL, three AF stages.



Today, I would class it as "Uncommon".  The Rectifier Power-Amplifier is probably Rare.  I've heard of two or three but never saw one.



Robert Downs - Houston

wa5cab dot com (Web Store)

MVPA 9480





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