[GPS_Standard] HP oscillator slowly moving

[Graham]

Likely just the crystal aging.
Most crystals will age at about 1E-7 per year

The spec on the HP10811 oscillator I use is 5 x E-10 per day.
You can see the normal aging of the crystal in the control voltage.

Calculate the equivalent frequency change for the control
voltage change you are seeing, and see if it falls in the normal
aging range.  If so, not much you can do about it.  Very normal.

--- Graham / KE9H

==

On 9/6/2012 3:15 PM, Chris Howard w0ep wrote:
> I've been running my GPSDO since May.
> It seems to work well.  We have had a couple of power
> outages and it gets sync'ed up again and continues on.
>
> After some initial fiddling around to get the control
> voltage near zero, I have just let it do it's thing.
>
> The control number is now 00710, steadily sinking over
> the weeks.
>
> I'm wondering if this slow movement is a normal pattern?
> My oscillator is an HP from an old frequency counter.
>
> I have log files from most of the period this thing
> has been in operation.  I put a local-computer time stamp
> on each line, so in theory I could graph the
> control voltage change if that would be of any use or interest.
>
> I guess I'm kind of concerned about the oscillator and
> wonder if I should try to acquire another.
>
> Any comments?
>
> Thanks!
>
> Chris
> w0ep
>
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