[time-nuts] Thunderbolt? (re simple gpsdo.) >> capacitors

[Chris Albertson]

On Tue, Jan 3, 2012 at 9:14 AM, Bob Camp <lists at rtty.us> wrote:

> Hi
>
> Using electrolytic caps in timing applications is a bit exciting. Their
> leakage current changes each time you change the voltage on them. It's
> enough of a change to significantly impact long time constants. In some
> cases the capacitance changes with voltage as well......
>

In general you are right.  But in this case the electrolytic cap is inside
a closed loop so as the temperature changes and the voltage in the cap
changes, the loop will correct it, as long the temperature changes slowly
compared to how frequently we measure the phase of the PPS signal.


You could always place the entire system inside box and control it to a
constant temperature.

-- 

Chris Albertson
Redondo Beach, California