On Wed, 06 Dec 2006 02:21:26 GMT, "Richard Knoppow" wrote:

I had always heard that PTOs would drift if the seal was
broken. Evidently they were filled with dry air. Some at
least have dessicators in them. Evidently low humidity is
important to their operation.

How would that cause drift? Couldn't it just be to prevent
corrosion, especially on the pickups of a roller inductor
inside?

I picked up the NPO caps yesterday, and I'm looking
forward to seeing if the cure the drift.

Dale