[Elecraft] Puzzled...

[Eric Swartz WA6HHQ - Elecraft]

It is a 5 kHz loop notch filter that further reduces the leakage of the 5 kHz 
PLL phase comparator frequency into the VCO's output.

73, Eric  WA6HHQ
----

Paul Bartlett wrote:

> I think I've just answered my own question. It's not on the ouput, it's in
> the loop. Part of the PLL loop filter?
> 
> ----- Original Message -----
> From: "Paul Bartlett" <paul@fulking.freeserve.co.uk>

>>Can somebody explain to me the purpose of C96 and RFC10 on the K2
>>synthesiser output.
>>
>>It provides no DC path and is high impedance at HF. It's series resonant
>>at about 5 kHz but that doesn't appear to provide any useful function.