copied from the internet:
Newsgroups: alt.radio.scanner
Subject: squelch mod for Pro-2002

You won't be able to receive 800 MHz on the Radio Shack
PRO-2002  without  a  converter, but you can tighten up
the squelch action by replacing resistor  R197,  a  47K
ohm resistor, with a 220K ohm resistor.
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