M. J. Powell wrote:
In message . edu,
William Mutch writes

The anonymous homebrew xmtr I picked up at the AWA meet last
spring has finally make its first QSO, heard 589 in Texas by KE5HQ on 40
CW, but he reports what I sort of knew anyway...the rig has a chirp. The
oscillator is an electron coupled 12BY7, crystal controlled. What are
the cures for chirp ?? Slightly detune the buffer ?? add caps to the
power supply. Trying the easiest things first, how should I proceed ??

My DX100 had a bad chirp. Cured by cleaning the key contacts with fine
emery paper.

If it ever comes to that again, don't use emery, or any abrasive paper, to
clean up electrical contacts.

The abrasive tends to embed into the soft contact material, and make for
contact problems.

The recommended repair is to burnish the contacts. That can be done by taking
an old hacksaw blade, and grinding the flat sides on a coarse grinding
wheel. The grinding wheel will put fine scratches in the saw blade's sides,
and these scratches make a pretty nice, very fine file... perfect for burnishing
key and relay contacts.

'Chuck