WWII BC221-M WAVEMETER

Used for Calibrating wireless transceivers. 125KHz to 20MHz heterodyne frequency meter with individual calibration book and internal Xtal calibrator.
Basic accuracy better than 0.034% over temperature range. HS-30 type headset or similar required for operation.
Supplied with one spare set of vacuum tubes inside unit, some units in 1942 were supplied with two spare sets.
Manufactured by Bendix Radio Corporation. Suffix M

Your comments:

• I have all three models covering HF VHF and UHF.
  Plus a mains power unit on one of them.Very high build quality and as stated used in later years to meet GPO regulations for an amateur license.
  
  David G8JET
  
  .......... David, S.Humberside UK, 14th of August 2017
  
  
• Known as "Wobbulator" to be used to tune R1155 and STR 18 HF receivers.
  .......... David Lloyd, United Kingdom Petersfield Hampshire, 11th of May 2016
  
  
• I have a photo, from a private museum in Tengchong; a BC221 from WWII, probably supplied to Chinese Army by allies via Burma Road; photo taken by bribing guards and aid of a torch. It seems to be an early version BC221
  .......... john seddon, London, UK, 24th of January 2016
  
  
• Manual - TM 11-300
  .......... Gary Oprendek, Marlton, NJ USA, 22nd of October 2014
  
  
• One of the truly great signal generators and receivers and still useful today. I would say probably the greatest creation of all time they swept all before them as workshop repairs devices. It is essential the setting manual serial number matches the unit number as they were individually calibrated. They came as your commenter said in many revisions and many forms and some went even higher in frequency than 20mHz (mC's). Unfortunately they have to some degree fallen by the wayside as solid state lightweight devices with convenient read-outs have been created but none of them has the majesty in your shack of the 221 in all its guises. This piece of equipment joins the BC 348, BC342 and ART-13 and "Command" sets as the 'quintessential' perfection in manufacture and progress as usable today as then (electricity bills to one side!!)
  
  These 221 and similar sig gens. are sometimes modified into receivers!...LOL..or QRP transmitters..though not exactly hand portable considering the power supply has to have car battery or mains supply ..but fun anyway though for me desecration LOL! .
  .......... Tony Clancy, Sydney Australia, 18th of November 2013
  
  
• There are quite a few versions of the BC-221. There is also a Russian made copy. Most amateur radio stations had one after WW2 as it was a requirement of the amateur radio licence that the operator should know his own frequency of transmission.
  .......... Ben Nock, Military Wireless Museum., Kidderminster, Worcestershire., 25th of February 2012
  
  

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