160M 1930s MOPA

1930s style MOPA running a 89Y Clapp ECO (oscillates around 900 kHz), 802 buffer, and 811 final.  Output is about 80-100W.

160m-mopa

Schematic of exciter (oscillator/buffer) section from which this transmitter is based.  89 circuit changed to a ECO VFO in actual rig vs. crystal control as illustrated in schematic from QST.

89-802-exciter-schematic

89 ECO schematic as actually built.  For 160M, oscillates around 900 kHz:

89-clapp-eco-2