[time-nuts] Trimble Thunderbolt setup optimizationand addinga10811 OCXO

[John Miles]

>
> I put in as K0 what I measured several times with the 10811
> as 'gain' with -0.74 Hz/V. Is that not the right way?

Yes, that's fine.  Because the varactor is nonlinear and a small part of the
overall tank circuit C, the tuning gain depends on the adjustment-screw
setting to some extent.  Specifying it within a factor of 2x is reasonably
OK, but it's always better to measure the actual gain by adjusting the
tuning-DAC parameter manually with the output centered at 10.000... MHz.

> I tried to
> use several times also higher values. The result was not impressiv,
> did not give clear signs either.
>
> A factory reset I did not perform yet, but I am trying at the moment
> the proposed 0.2 or even a bit lower values. Tomorrow I will
> check the result, but up to now I do not have a good feeling.

I just pulled my 10811-equipped TBolt out of storage after several months,
and it powered up in a rather confused state.  Before I did a factory reset
on mine, the reported PPS/10 MHz deviations were entirely fictional.  It was
reporting reasonable values, but in reality, it wasn't steering the
oscillator closer than a few parts in 1E-8.  The factory reset cycle fixed
the odd behavior (note that you have to re-enter the tuning-sensitivity
parameter after doing that).

-- john, KE5FX