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The discriminator IC in the Uniden Bearcat 100XLT and 200XLT is a
TK10421. Pin 11 contains the unfiltered audio.
This IC can be found on a vertically mounted PCB, called 'IF Unit'.
Test point 3 (TP3) contains a signal coming rather straight from the
discriminator, but it is filtered too much to be of use.
A limiter resistor of 10k is fixated to the IC with a drop of glue from
a glue gun. As the discriminator output contains a slight IF component,
a simple RC-filter is created by adding a 2.2 n capacitor. The cutoff
frequency of this filter is about 7 kHz. The capacitor is connected to
the metal frame of the scanner.
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