WWII BC 453 B SIGNAL CORPS RECEIVER

Part of a group of equipment known as 'Command' fitted in aircraft for general crew use.
Although the radio operator and pilot could use the communication equipment on board, the general crew could not, but they were allowed to to use 'Command' Equipment.
This particular portion of the system ( SCR1305A ) , was a beacon receiver for tracking a fixed course by following a beam from a distant transmitter, (similar to 'get you home' beams).
Other equipment of similar size and weight would be Transmitters and Receivers for R/T communication ( voice ) . The aircraft's normal Transceiver would be CW ( Morse ). Frequency 190kcs to 550 kcs

Your comments:

• The 946 is one of the rarest...you can tell by its nomenclature it was a later series. I have one, they are quite sought-after although the current generations have pretty much lost interest in using WW11 gear.
  
  I will not go long into the massive information available about the "Command" sets....which were not only this series but a designation of communication covering a system...and the AN/ARC-5 SCR and similar designs were similar in looks to the one shown. These were lightweight, compact, stable and as far as hams were concerned brilliant.
  
  The BC453 was used by us as a "Q5" for narrowing Intermediate Frequency bandwidth to 50KHz for paring off the noise accompanying CW (Morse) in poor conditions though the sets were and still are used on AM transmission by traditionalist Hams.They were used as a glide path receiver and still much transmission goes on at those lower frequencies.For at least 50 years 500kHz (kCycles before that) was the international emergency frequency and for example my ART-13 transmitter, used by Panam for many years after WW11 and with the comparatively rare USA "Communications Company" conversion of the Very Low Frequency section to more extensive crystal control for ease of airline use still has its 500kHz (kC's) crystal in there amongst the others.
  
  Command sets were used commonly with in-aircraft communication as well as inter-aircraft and Command communications (remember the term "bomber-command"..? . Photos of this gear and the BC348/ART-13 are readily seen on internet as installed in aircraft and much of the WW11 gear was still in use in commercial air planes into the 1970's....WW11 produced some brilliant design and incredibly good construction particularly from USA.
  
  Today highly skilled in design, solid-state design factory pop-outs from Japan might have far better specifications but have no character whatsoever, they are virtually a telephone set. For real Ham fun and the challenge to experiment..which was a Ham essence...these traditional developments in am and cw which we see in famed military radios are unbeatable, specifications are not the be-all and end -all of self entertainment and the skill in making good equipment do great job.
  
  Single Side-band, the energy and frequency space saving development of AM (which is what you hear on your 530-1500kHz 'am radio' can be clearly received on any set with a stable beat frequency oscillator but SSB transmission with these wartime sets requires a rebuild.
  
  It may be hard to believe for later generations for whom it's 'buy plug in and start talking but in Basil Fawlty intonation..."don't mention CW"...' that these fabulous radios saw their actual design in the early 1930's...the BC 1206, the BC348 and its allies, the 'command' series, the National HRO...one of the WW11 most used surveillance receivers and still almost a status symbol....and so many others...
  
  The Collins ART-13 is the epitome of wartime design but these little "command" set (the transmitters of the series) still can and still do as they are still used by traditionalist Hams...easily perform world wide communication on cw.
  
  Thank heavens with the peculiar decision to scrap cw as a communication a lot of Hams still use it.
  
  The dynamotor at the rear were commonly removed and a small mains power supply built there in its place...the little lower front panel 'cover" with the knob was in fact an alloy box and was used by hams to include signal level controls and a switch. All the tubes are still available.."new old stock" (NOS) from WW11 and later.... The outside view here hides the brilliant interior design and workmanship.
  
  The demand for tubes...50 years after the advent of transistors....is still very strong world wide and Russia turns out large numbers of extremely good tubes.
  
  Though mocked by people who claim to be audiophile experts these Russian tubes are very well made and perform very well. You may be surprised that a market still exists particularly in "the west" for valves/tubes and radios themselves...and crystal sets...going back into the 1920's when radios were a work of art and continued to be so until late 1950's when much of that art went over to transistor sets.
  
  Even then replicas of the great tube era art have long been used with transistor-set insides.
  
  If you don't know much about this military gear...search the internet...you may find it very interesting and give some thanks, literally, to the Museum if you find it so.Your life could take on a fascinating new journey.
  .......... Tony Clancy, Sydney NSW, 18th of November 2013
  
  
• The cylindrical item at the rear is a dynamotor for raising the aircraft's low voltage to a level capable of operating the receiver's valves.
  .......... Laurie Booth, Emsworth, Hampshire. U.K, 25th of June 2011
  
  
• BC 453 190 - 550 KHz
  BC 946 520 - 1500 Khz
  BC 454 3-6 Mhz
  BC 455 6-9 Mhz
  All use the same basic platform. my 60 year old BC 455 works just fine!
  .......... Nick Wilson, Solvang, California, USA, 24th of January 2011
  
  

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