The 11BY was a five tube, single band, AC/DC powered series-string superheterodyne.

The tubes used in the 11AB, a set known as the All-Americal five, are:
12SQ7 Detector, AVC, 1^st. A.F.
12SA7   Oscillator/Modulator
12SK7   I.F. Amplifier
50L6   Output
35Z5   Rectifier