The BC348 Series of receivers were part of the “Liaison” radios aboard numerous WW II era aircraft including the B-17 Flying Fortress and the B-29 Superfortress. Unlike the SCR-274N “Command” radios which were used for short distance air-to-air and air-to-ground communications, the “Liaison” radios were used for long range communication

And, one of these days, when I have some time, I’ll expound upon that. But for now, here are some pictures of my BC-348Q.

By the way, if you plan on actually using your BC-348 on the air….

Take the time to replace all the paper caps and check the resistors. You can check a lot of the resistors in circuit, and quite a few others by unsoldering either the resistor itself or a nearby component.

In particular (and this is for the Q model, but it should be similar to other models):

-- be sure to replace the audio plate bypass capacitor 24-2. If it goes it will take out the primary of the audio transformer (see pictures below).
-- check the filament dropping resistors 84 and 85. Mine were discolored and way out of tolerance.

Rebuild the dynamotor if you have one. It's straight forward and can be done in a few hours.

Antenna / RF / Detector / Oscillator (sub)Assembly Photos

Bypass Capacitor Locations 1

Bypass Capacitor Locations 2

Copyright (c) Mark S. Bell 2013 - 2019