Archive for January, 2013

“Remember” 6V6 “Slat Board” Oscillator Crystal Chirp

January 7, 2013

The original “A Single Tube Transmitter” article the December 1946 QST magazine author Bryan Goodman, and reprinted in the 1948 ARRL Radio Amateur’s Handbook was the inspiration for Pastime Project’s “Remember When” 6V6 transmitter kit which has been available for about six years.

The original was designed to use 80 meter crystals on both 80 and 40 meters.  For several reasons – including reduced output – today’s amateur would prefer to use 40 meter crystals.

Our manual has suggested several simple modifications to improve the chances of  success with reduced drift and chirp.  Sometimes these ideas worked, and sometimes they did not.

Pastime Projects went back and looked at the engineering of the original “Tri-tet” oscillator and modified the cathode LC circuit to improve performance.  As a result of early tests,  Page 17 of the Pastime Projects Assembly Manual has been updated.  Here you will find further detail on the fix.

If you have purchased the “Remember When” 6V6 kit from www.pastimeprojects.com  in the past,  simply email for a copy of the revised page 17 “Crystal Selection”  for your manual.  

Very best regards   Glenn  pastimeprojects(at)yahoo(dot)com