[time-nuts] What to do with your dead cesium

[Dave Mallery]

beautiful.

we should create a compendium:  '101 uses for a dead cesium'

On Mon, Apr 20, 2020 at 9:50 PM Skip Withrow <skip.withrow at gmail.com> wrote:

> 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
> _______________________________________________
> time-nuts mailing list -- time-nuts at lists.febo.com
> To unsubscribe, go to
> http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com
> and follow the instructions there.
>


-- 
Dave Mallery, K5EN                 (ubuntu linux 19-04)
80018 Lobo CP                             Grants,  NM  87020

      linux counter #64628 (since 1997)