Selectivity enhancements

[Jim Berry]

One of the best means of simple and cheap selectivity improvements I
have found is a simple audio filter.  The things are variable from
several hundred Hz, down to say 100 Hz or less.  The only hitch is
they are not in the IF.  A big signal can still swamp your old
receiver.  Another problem with these filters are they are solid
state.  You get caught with one, you may loose your BA friends.
Thing is, they just go in line with your audio and are rather easy to
hide.  A really good one can be bought new, in kit form, for less
then 20 bux, and picked up at a swap for a couple of bux.

73 Jim K7SLI

>
> I'd like to see some views on "selectivity" in these old tube