[time-nuts] EFC Input pin impedance for the HP 10544Aand10811-6011

[Bruce Griffiths]

Don Collie wrote:
> So, what *is* the input impedance?
> Cheers,...............................................Don.
>
>   
It depends on the frequency.

Network is complex 20k in series with 100-200pF plus another 20K to
signal ground plus a few pF shunt C from the varicap to ground (a few
pF) for the 10544A as a first approximation.
For the 10811 100K in series with the 100pF varicap plus a few pF in
paralle with 100K to signal ground.

Bruce