Hello I wander if the guts from the dismantled cesium are available for a "transplant" in order to save a non working fe5440 with good tube. Thanks Emmanouil sv1bke
------ Original Message ------ Received: Tue, 21 Apr 2020 06:50:49 AM EEST From: Skip Withrow <skip.with...@gmail.com> To: time-nuts@lists.febo.com Subject: [time-nuts] What to do with your dead cesium Hello Time-Nuts, Well, with the COVID-19 stay at home order I have been working on a couple of projects (at home). This post shows what I have done with an old FEI FE-5440A cesium standard. The tube was dead, so I decided to turn it into a GPSDO. I ripped out the tube, HV supplies, modulator, and OCXO. The battery was already missing, so it was replaced with a couple of SLA units. I decided to use a TruePosition GPSDO since it was small (I just wish it had a LOCK indicator). An SMA antenna connector was added to the rear panel. Basically, the 10MHz from the GPSDO feeds the distribution system in the FE-5440A. The TruePosition 1pps was brought out to the front panel, and can be used to synchronize the clock in the unit. An RS-232 DB-9 was put in place of the C-field control so Lady Heather can monitor. Some of the nice features are: 10MHz, 1Mhz, 100kHz, 1pps, and 1ppm front panel BNC outputs. Front panel clock display (that is easily set from the front panel) 1pps (FE-5440A) can be offset from 0-1 sec in 100ns steps from the TruePosition 1pps Battery backup (greater than 2 hours) and DC input, as well as AC input I don't know about the phase noise performance, but ADEV is probably better than the original standard (as long as there is a GPS antenna connected). I have attached a couple of pictures of the unit plus a 5-day TimeLab plot. Regards, Skip Withrow > --------------------------------------------- > Attachment: FE-5440A-1.jpg > MIME Type: image/jpeg > --------------------------------------------- > --------------------------------------------- > Attachment: FE-5440A-2.jpg > MIME Type: image/jpeg > --------------------------------------------- > --------------------------------------------- > Attachment: FE-5440A.jpg > MIME Type: image/jpeg > --------------------------------------------- _______________________________________________ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.