Hi again James

Should have read your original post more carefully - sorry !

On Tue, 25 Apr 2006 23:06:39 GMT, biascomms
wrote:

James Thompson wrote:

Has anyone got a good but cheap circuit to eliminate or surpress feedback.
Im making my son some low power fm mikes to use in his church, but they
get feedback real easy. Is there a simple notch filter per say that I can
add
the the mike section of this. My pcb is only 1.5 by 2" right now.
Thanks.

I guess that you could build a speicific notch into the mic pcb - but
that'll only work if the feedback is at one specific (resonant)
frequency. I think the best filtering systems are 'adaptive' - in
that they can spot feedback happening and can drop a tunable notch on
top of it in real time. Complicated though - and tends to be done at
the amp, rather than at the mic.

All the stuff in the other post applies though - look at the system
first......

Adrian
Suffolk UK
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