The xtal oven went bad and I sent the O VI into TT to have a TCXO put in,
and a realignment done.. Now it's about 50hz low.. I can adjust for this,
but, that just doesn't set right with me.. I'm assuming the problem is
ageing of the Master Oscillator (TCXO)..
Ten Tec's TCXO is actually quite good. You may only need to re-adjust it
one last time after initial aging. I also retrofited mine and its frequrncy
did not vary more than about 10-20 Hz over time.
My setup is a "Closet Kilowatt", and it's a (PITA) to take apart and
readjust the MO.. There are some more conveniet and long term options..
1. Move the TCXO/Xstal Oven outside the cabinet..
2. Install a better MO unit..
3. GPS timing system..
4. Bottom line a remote MO..
I would be apprehensive about moving the TCXO too far from its present
location. I do not recall the TCXO's frequency, but if it's 10 MHz, you can
use a GPS-locked disciplined oscillator, like the HP Z3801A.
Another option is an ultra-high-stability, low phase-noise OCXO like this
one from Wenzel:
http://www.wenzel.com/catalog/4to24.html#onyx
Either of these options is going to be a bit pricey with the OCXO probably
requiring the least amount of modifying to the rig.
Paul, W9AC
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