On 2005-07-21, Samuel Hunt wrote:
I'm planning to build a AFC system for SSB, which has a 1khz pilot tone that
will be used to lock the frequency correct.

If you are going to lock onto it so that that signal is exactly 1khz,
why not just cancel it with a 1khz signal 180 degrees out of phase?
This is essentially how an FIR filter would remove it digitally, but
you don't really need to generate the tone FROM the signal since you
know what it is already.

--
Ben Jackson

http://www.ben.com/