Boeing B-29 Commuications Flight Deck
http://aafradio.org/flightdeck/b29.htmThe BC-224-A, -B, -C, and -D; and the BC-348-B, and -C, tuned 1.5-18 MHz in six bands.
The Signal Corps had the receiver design modified to add a 200-500 kHz band and compress the 1.5-18 MHz coverage into the remaining five bands.
This modified design became the BC-224-E and the BC-348-E.
The 200–500 kHz and 1.5-18 MHz tuning range remained constant for subsequent production of all models.
http://en.wikipedia.org/wiki/BC-348BC348 receiver page -- James A. Moorer
http://www.nonstopsystems.com/radio/bc224-bc348-page.pdfBC-348 receivers were copied and manufactured by the U.S.S.R. following War II by the Russian Vefon Works and labeled УС-9 (US-9 in English, US as Universal Superheterodyne, not United States.)
The УС-9 continued to be produced in the Soviet Union through the 1970s, with such improvements as a solid state inverter to replace the dynamotor.