[Heathkit] Phase networks tone frequencies.

[Kenneth G. Gordon]

On 22 Sep 2007 at 13:44, Peter Markavage wrote:

> The bottom line is that it really doesn't make much difference if the
> output tone frequency has shifted due to component aging.

Well, as with a lot of things, "that depends...". 

In the case of the HW/SB transceivers, that tone frequency must be 
fairly accurate since matching that tone to a received CW signal gets 
you pretty close to zero-beat with the other fellow. If the tone is too far 
off (mine is at least 300 Hz high in my HW-101 right now) it makes it 
darned difficult to get on the NCS' frequency on the CW nets.

Of course, in those rigs, the various "BFO" crystals have to be 
properly placed in the filter passband too.

Ken W7EKB