Note
QST Nov 1940 p. 9.
QST, Jul 1941, p. 92.
QST, Feb 1946, p. 142.
Radio News, Apr 1946, p. 12.
Lafayette catalog number 88 (1947), p. 106.
Millen catalog "Communications Receivers and Transmitters" 1947-1948
Lafayette catalog number 89, p 170.
Walter Ashe catalog, 1954, p. 9.
Based on a project appearing in the 18th edition (1941) of the Radio Amateur's Handbook, pages 149–152.
Uses a 6L6 crystal oscillator-doubler or beam tetrode crystal oscillator, driving an 807 amplifier or doubler. The 6L6 may also be used as a frequency doubler driven by a VFO.
The transmitter can deliver at least 50 watts on 80, 40, and 20 meters, and by doubling thje frequency in the 807, can deliver about 20 watts on 10 and 11 meters.
Because it is possible to double or quadruple the frequency in the plate circuit of the oscillator, and to double the frequency in the plate circuit of the 807 as well, there are several possible combinations of coils and crystals that will provide the same output frequency. Out of the box, the 90800 was supplied only with a 10 meter coil for use with 40 meter crystals, less tubes.
The five-pin front panel socket is for the crystal or VFO. The toggle sqitch above the socket is used to switch the cathode coil in or out.
Meter reads to 200 mA and may be switched to the the plate current in either stage.
Power requirements:
Up to 750 VDC @ 250 mA (807 max rating)
45 VDC fixed bias for the 807
6.3 volts at 1.8 amps
Tubes: (1) 6L6, (1) 807
Modifications. CQ, Oct 1963, p. 41.
