Note
QST, Dec 1946, p. 123.
Lafayette catalog number 88 (1947), p. 99.
QST, Feb 1947, p. 158.
Millen catalog, 1948
Millen 90881 operating manual
Walter Ashe catalog, 1954, p. 9.
The 90881 comes out of the box wired for use with 812 tubes, but includes instructions for rewiring for use with Taylor TZ40, Eimac 35T, T55, HK154, RK35, and others, providing an output approximately 380 watts.
Used 42000 series plug-in inductors with "swinging link" antenna coupling for the plate circuit, and 43000 series inductors for the grid circuit.
One set of coils provided (customer's choice).
Individual meters for grid (100 mA) and plate current (500 mA). Plate tuning capacitor (Millen type 16060) has constant low impedance and multi-finger high current rotor contactor, and is rated at 6000 volts. Disc-type neutralizing capacitors (Millen type 15011) have a stop to prevent shorting, and a rotor lock.
Ideal for use with the Millen 90800 or 90810 transmitters. Use with the Millen 90281 (or equivalent) high voltage power supply.
Frequency range: 1.8 to 30 MHz with plug-in coils
Excitation power: about 18 watts
Power input:
AM – 350 watts max
CW – 520 watts max
Power requirements:
Normal: 1000 VDC @ 230 mA
Maximum rated power input: 1500 VDC @ 346 mA (520 watts)
6.3 volts at 8 amps (for 812-A tubes)
Tubes: (2) 812-A
