The W8EXI Wingfoot VFO Exciter
High Technology In The 1950's
by Greg Latta, AA8V

Block Diagram

exciter top

Wingfoot VFO Exciter Pages:
Introduction and Front and Side View Photos

Power Supply, Interior, and Rear View Photos

Schematic Diagrams and Circuit Descriptions

Special Features

Block Diagram

Chassis Layout

General Information: The Wingfoot VFO Exciter is a CW transmitter of the frequency multiplying type. The VFO operates on 3500kHz and is run straight through on 80m, doubled for the 40m band, and quadrupled for the 20m band. For 30m band the VFO operates on 3367kHz and is tripled. A final amplifier featuring variable regulated screen voltage operates straight through on all bands with an output continuously variable from 3W to 27W. A clamper tube protects the final amplifier in case of loss of bias for any reason. The transmitter features differential or timed sequence keying to provide clean, chirp free keying.

Block Diagram
Click On A Section of the Block Diagram
Below for Information on That Part of the Circuit:

Block Diagram Clamper/Screen Regulator Circuit Final Amplifier Circuit 2nd. Buffer/Multiplier Circuit 1st. Buffer/Multiplier Circuit Cathode Follower Circuit Oscillator Circuit Differential Keying Circuit

Or click on one of the links below:

Block Diagram
 Cathode Follower
 1st. Buffer/Multiplier
 2nd. Buffer/Multiplier
 Final Amplifier
 Clamper/Screen Regulator
 Differential Keying

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