Need Digital Scanner???

[Fiveo]

I'd like to use Unitrunker or similar program to monitor a APCO P-25 Digital System (MI Statewide MPSCS system). Does the radio I tap need to be a digital scanner or does the software take care of decoding the digital signal? I'm hoping a plain jane 800mhz scanner will do the trick, as I'm not real comfortable getting into the guts of my $500 digital. Also, does Unitrunker cover this type of system or is other software needed?

 

[SCPD]

Does the radio I tap need to be a digital scanner or does the software take care of decoding the digital signal?

No - the radio providing the discriminator audio does not need to support digital voice or trunking. It just needs to be able to tune to a control channel.

I'm hoping a plain jane 800mhz scanner will do the trick, as I'm not real comfortable getting into the guts of my $500 digital. Also, does Unitrunker cover this type of system or is other software needed?

Yes it does. I've used a PRO-83, PRO-91, BC245XLT, BC780XLT, and WinRadio for discriminator audio. The signal from the PRO-83 is very low level and needs a buffer amp (otherwise the squelch stops working and it won't scan) to isolate the radio from the computer. I've also found that a buffer amp improves P25 decoding in radios that otherwise provide solid decoding of Motorola and EDACS.

Tip: start with the Uniscope utility to verify a decent signal into the computer.

-rick

 

[polo_762]

Do you need to do a tap?
or is it possible to monitor the digital system with control channel audio from a headphone jack?

 

[SCPD]

Do you need to do a tap?

For Unitrunker - yes.

is it possible to monitor the digital system with control channel audio from a headphone jack?

The audio is filtered for noise and hiss which also destroys the waveform. For purposes of decoding a digital signal - this makes speaker / headphone audio useless.

For P25, the PRO-96 and PRO-2096 can do so without a discriminator tap. They'll pass the control data over the serial port to a computer. Look for a program called Pro96Com.

-rick