[time-nuts] Z3801A OCXO manual trimming

Tom Van Baak tvb at LeapSecond.com
Sat Mar 3 22:25:23 EST 2018


> Interesting point about the heater not working vs. the XTAL having drifted too far.

Any logs you made of EFC percent over the past few months or years will help verify the off-the-rail theory.

Another thing to try -- turn-off the Z3801A for a couple of hours to let it cool. Disconnect the GPS antenna. Then power it up and monitor the frequency, say every 10 s or a minute, until it stabilizes. The shape of this warm-up curve will give you a hint if the oven(s) are working. Repeat the test with the outer oven disconnected to test the inner oven by itself.

/tvb



More information about the time-nuts mailing list