Pro-106 Discriminator Tap
From The RadioReference Wiki
With thanks to fourthhorseman for the photos. The Discriminator output is available at Test Point 4 (TP4). This tap can be used to feed applications such as UniTrunker (although with UniTrunker, it's not really necessary, since the PC/IF datastream will also work). See our Trunked Radio Decoders article for more information.
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