[time-nuts] PLL/GPSDO/etc learning resources for mere mortals

Jim Harman j99harman at gmail.com
Tue Sep 4 12:39:12 EDT 2018

To be clearer, I should have said that it helps to stabilize the
temperature of the whole system, to make the thermal time constant longer
than the response time of the loop.

I have found that putting the GPSDO in a picnic cooler with several large
water bottles reduces the impact of daily temperature fluctuations. Some
people recommend more extreme measures, such as burying the system several
feet underground.

On Tue, Sep 4, 2018 at 12:28 PM Jim Harman <j99harman at gmail.com> wrote:

> The challenge seems to me to be
> how to temperature stabilize the entire DAC chain without putting it all in
> an oven
> Hi Forrest,
> Generally you don't have to temperature stabilize the DAC because it is
> inside the phase-locked control loop and the loop will adjust for
> temperature dependencies, just as it adjusts for drift and temperature
> dependencies in the oscillator. You will want your phase detector to be
> reasonably temperature stable however.
> In the time-nuts archives you will find posts from Lars Walenius and
> myself with schematics and code for Arduino-based GPSDOs which you might
> want to study.


--Jim Harman

More information about the time-nuts mailing list