W0BVT Pictures JANUARY 2014

W0BVT's HOMEBREW CX RIG


Attached is a picture of my Classic Exchange station used during the event today. The transmitter is a H.B. 807 oscillator modulated by a 6L6 Heising modulator. Output power was 5 watts. I use a regulated D.C. power supply for B+ and monitor the output with a bench scope. Channel 1 of the scope feeds a frequency counter. The Receiver is a Drake 2A and the antenna is a 75 meter dipole on a 75 foot tower.

Plate voltage to the 807 was 250 volts at 50 ma., or 12.5 watts input. Given 5 watts output that computes to 40% efficiency. Not bad for a modulated oscillator transmitter.