[Milsurplus] BC-348R

[Glen Zook via Milsurplus]

Remember, when attaching an AC power supply to the BC-348 series, the B- does NOT go to the chassis!  The B- connection is above ground which provides, among other things, the bias for the audio output.  Connecting the B- to the chassis can cause problems including greatly reduced life of the audio output tube. Glen, K9STH

Website: http://k9sth.net
      From: "k2cby at optonline.net" <k2cby at optonline.net>
 To: milsurplus at mailman.qth.net 
 Sent: Saturday, July 11, 2015 2:01 PM
 Subject: [Milsurplus] BC-348R
   
Although I've been a ham since (good grief!) 1957, I've never owned a
BC-348.

I found a bargain on ebay and picked up a BC-348R just to see (hear) what
the WWII Air Corps operators used.

I downloaded the tech manual T.O. 12R2-3BC-112 and was appalled by the
schematic. Not only is it small scale, but it uses 1920s-style symbols and
drafting conventions. The bandswitch diagram, in particular, looks like a
spaghetti factory after an explosion.

Does anybody know whether a print is available that is easier to decipher.
The scale isn't too important so long as it is clear enough to enlarge.

 

The unit I bought had neither a dynamotor nor power supply. Does anyone have
a suitable (220 v B plus at 70 mils) power supply or transformer for sale?
Fair Radio's transformer prices are beyond belief, and most of the stuff on
the internet either has no specs at all or way too much voltage.