easiest thing for some p25 finding is to set search/clocall opt --- tone code search to p25 nac search then let your radio search and store in the freq ranges you want in search ,,, finds some of the voice stuff but not all , you look through the no nac found stuff to find ones with control signals
As discussed there are some work arounds that can provide some digital only frequencies, with Proscan there is another option. If you go to custom search, select a custom search button, then select contral channel only. Mant p25 systems are trunking so they would have a control channel. This will locate control scannels. Now single p25, this won't work but this should provide some answers. As has been reported, there is no real way to get digital only, but there are a few ways that digital "some" can be recorded.