On Dec 16, 12:32*am, Ian wrote:

Try a new battery. I had the same symptoms with a Becker + Ameriking
encoder. A new battery made them go away.

Thanks for the tip but this is a PA28-180 with an alternator. Problem
was intermittent last winter, gone in the summer, and back again now
winter is here. I'm in the middle of some cold soak testing but
results so far point to the encoder (ACK A-30).

Andy