Re: Blues Blaster Mic - Capacitor

[Bruce Steinberg <bruces@xxxxxxx>]

        From: timm@xxxxxxxxxx (Tim Moody)
        Subject: Re: Blues Blaster Mic - Capacitor
        
                                <...>

        Someone mentioned that since that cap was a small value it must only
        be good for RF frequencies that might stray by.  I don't think so
        because if they were RF you're Audio band amplifier would ignore them
        anyway.
        
////////////////

If that were only true.  Unfortunately, anyone who has ever heard
a strong local radio station coming through a poorly shielded
audio amp or telephone (or even some folks' fillings) is
listening to an RF signal being demodulated for its AF component
by some poor device that was never meant to be overdriven into
non-linearity.  Under the "right" conditions, any low-level audio
amp can effectively become a big overloaded diode detector for
that powerful AM station right down the road.

Again, I'm not saying that the primary purpose of that capacitor
is shunting stray RF picked up by the mike element from going
down the shielded mike lead to the amp, but just that it might
still play that role in part.  (Similarly, when the phone company
tries to kill RF interference on incoming house lines, they
install these little RF chokes -- inductors -- in ~series~ with
the lines, right out at the junction box.  Same idea.)  B*