[time-nuts] GPSDO simulation tool

[Magnus Danielson]

On 24/03/14 07:12, Hal Murray wrote:
>
> magnus at rubidium.dyndns.org said:
>> I did a temporary hack on the PID code to convert the D-term into I^2  term,
>> by integrating the integrator output. First attempt was indeed  quite
>> resonant just to show that I was in the unsafe region. Backing  down on the
>> strength of the component sure did remove much of the  resonance, but I did
>> not see any appreciable improvement in filtering  performance, so quick and
>> dirty hacking isn't sufficient, darn.
>
> Maybe it isn't sufficient to make a great GPSDO, but it's more than
> sufficient to point out the advantages of Tom's simulation setup.
>
> Thanks Tom.

Did some home-work on third-degree PLL parameters, so now I know why I 
failed, as I never tried to do it right.

One thing that Tom's simulator isn't doing is calculating the parameters 
for the PID for you, or backwards what characteristics you will get.

Cheers,
Magnus