Problems receiving P25

mr.syntrx · Post by **mr.syntrx** » Sat Aug 14, 2004 4:27 am

I'm currently helping a guy get his XTS3000 set up to receive conventional P25. The problem is as below. We've got the RX Unmute Rule is set to digital CSQ, and the RX Signalling Type is set to ASTRO. The RX and TX Network IDs (even though these are receive-only channels) are set to 293 (default). He can hear the dispatcher, but he can't hear the other units on the channel. Any pointers would be appreciated.

I have set the Rx Unmute Rule to Digital CSQ. The Network ID for TX and RX is then grayed out and defaults to the value 293.

I can now receive the AFP in Canberra but at this stage only the Radio opperator. The cars and portables are not coming through. I get the ID: display come up on RX as well which looks neat.

The other thing I have observed is when the operator is talking the RX indicator light flashes only once constantly and when the cars or portables tx the RX indicator double flashes between each flash.

Need to figure out this one now.

Post by Pj » Sat Aug 14, 2004 7:23 am

It is possible that its encypted on the inbound side. I would try to find a Uniden Digital scanner and see if the scanner show ENC.

ScannerDan · Post by **ScannerDan** » Sat Aug 14, 2004 8:04 am

Maybe it's a simplex system and they don't use a repeater ? If it's simplex then you would only hear the dispatcher and not the units unless they are close to you.

Just a thought,

Dan..

2wayfreq · Post by **2wayfreq** » Sat Aug 14, 2004 11:33 am

Hi,
Check to see if the RX light blinks twice rapidly and then over and over. That is encryption. If you set up a button to unsquelch the signal, you will hear it.

mr.syntrx · Post by **mr.syntrx** » Mon Aug 16, 2004 3:09 am

Yep, it's encryption (according to an associate in Canberra).

I was told that the dispatcher's traffic is clear so if an officer's radio loses the key for some reason (smacking a prisoner hard enought to knock the battery off his Astro Saber for example), he can get on in the clear and ask to be rekeyed over the air.