[time-nuts] Aging rate of crystals

[Jason Rabel]

> Did you look into /why/ the 10811 was humidity sensitive? The
> resonator and most individual board components are sealed, so
> that doesn't leave too much. Maybe the coarse tuning variable
> capacitor, which is exposed to air through its 2 mm hole?

When I was reading Rick's post, I immediately thought of the coarse
adjustment hole / cap too. I wonder if plugging it up and taping over the
hole would help any?

> Do you know if most modern high-end OCXO, which are solder
> sealed, and which have no screwdriver tuning access hole, are
> immune from all humidity variations?

MTI-Milliren has some specials right now, someone could get one of their 250
or 260 series sealed oscillators for < $150 and run some tests...