Corby, Nice detective work. Keep us posted. I had a case some years ago where my IF level was sputtering around. It turned out to be the dissociator. It was a pretty easy fix after a fax / email or two from Russia.
If you suspect the L.O. you can always free-run it for a week and see if similar symptoms occur. That would eliminate 99% of the complexity of the maser as the source of the problem. /tvb ----- Original Message ----- From: <[email protected]> To: <[email protected]> Sent: Monday, August 13, 2018 1:07 PM Subject: [time-nuts] EFOS2 Maser acting up :( > Hi, > > The EFOS2 Maser is having an "issue", the I.F.level is intermittently > fluctuating and sometimes drops all the way to zero. I've always wanted > to see the "raw" output from the cavity so now was my chance! Installed > two SMA cables bringing the output of the circulator and the input to > the LNA out to where I can get at them. Managed to catch it at zero and > hooked a Spec-A to the output of the circulator. Hooray, The Maser cavity > output is good, so the problem lies downstream. Installed a directional > coupler between the two lines looking back into the LNA. Can see a > healthy 1440 Mhz L.O. leakage and logged a reference level. Now just > waiting for it to drop again and see if it's the L.O. If not I'll have to > dive in again and move my monitor SMAs to look at the 19.6...Mhz I.F. > signal. Pix shows the cavity signal on the spec-A. > > Cheers, > > Corby -------------------------------------------------------------------------------- > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
