Knight B10506 "Candid," 1940
Tube complement: 1R5 mixer/oscillator, 1T4 IF, 1S5 detector/1st audio, 1S4 audio output.
Approximately 8-3/8 inches / 213 mm tall, not including handle.
In late 1939 RCA introduced the first four tubes (the ones listed above) in its new series of miniature tubes. Together they formed a tube set suitable for making a complete battery powered superheterodyne radio. More commonly seen under the Sonora brand, this radio was introduced in April 1940. It was the first to use these new miniature tubes that were to become so common after WWII.
Truly portable, with efficient battery powered circuit and built-in loop antenna, this radio was ahead of its time.