PRO 106 and Encryption

[W4EMS]

Monitoring TN State Capital site. The recently rebanded and went digital. TG have been clear but this AM hearing 57712 but only dispatch. I am guessing that means the portable/mobile is encrypted and thus the PRO-106 ignores it?

Thx
Doc

 

[zerg901]

My Pro106 gets some messages that sound like Daffy Duck on speed - I believe this is encrypted traffic. Info / listings from the Internet pretty much confirms this. Therefore, I dont think you are dealing with an encryption problem. Peter Sz

 

[bama9999]

Are you sure you have all the control channel frequencies programmed? As zerg901 said, you can hear encrypted P25 traffic on a Pro106, you just can't understand it.

 

[W4EMS]

Thanks. All of the cc's are programmed and 99% scale. I agree that you usually hear them as garbled that is waht puzzles me. I am considering that perhaps the dispatcher is simulcasting on two TG's and I am missing the reply as the mobile is on another. Brought a second scanner in today to try and track it down work allowing.

 

[zerg901]

Maybe rebanding is not totally completed yet, and they are doing some sort of funky dual system operation. Or maybe they turned off the "repeat" function on that channel or talkgroup - for whatever reason. Peter Sz

 

[GTR8000]

doctree - You have the scanner setup for a rebanded system, correct? And it's set to CC Only mode? If you have a second scanner handy, I suggest programming in all the system frequencies in conventional mode, lock out the active CC, and scan the others for activity while listening on the PRO-106 having the issues. If you start hearing conversations directly on the repeaters in conventional mode, but the 106 is not trunking, then something is clearly not right with the programming. If you're getting the same results in trunked and conventional mode, hearing only one side of the conversation, then it sounds like a much bigger issue beyond your control!

Are you sure you have all the control channel frequencies programmed?

A Motorola Type II system can have up to four CC's, only one of which can be active at any given time. Theoretically, a system can stay on the same CC forever, never switching to the other 3, but that's usually not the case. Anyways the point being, you really only need to have the active CC programmed at any given time, the other three are irrelevant. You would know right away if you didn't have the active CC programmed, because the scanner would simply not trunk track at all. Since the OP has indicated that he's getting TG activity, the problem is not the CC's but rather something else.

 

[W4EMS]

Well listening today the dispatch side is broadcasting on two separate TG's, primary and a "secondary" while mobiles are on the primary only. Not sure if intentional or a key is stuck or just something funky.

 

[W4EMS]

As for cc's I checked them all and this system pretty consistently uses one for the cc. Nothing on the pre-band frequencies. They may be using the secondary TG to crossslink to a non-TRS repeater. As I look thru the frequencies TSU has a separate repeater for the downtown unit. Need to see if the other TG is linking dispatch to that machine and then listening back on the conv repeater output.