On Wednesday, April 15, 2015 at 9:52:17 AM UTC-7, Ron Gleason wrote:
Thanks Burt. We will see what the club wants to do.

If it's a simple switch + potentiometer you may be able to measure resistance at several points and find a replacement at Mouser or somewhere like that. If it's just a dirty pot, you may be able to use some cleaner on it and get a few more years out of the existing one.

Good luck,
Craig