PSR-500 settings issue?

[darrylcn]

Thought I would check here in case anyone knows a solution. It may be the system's fault, not my scanner's but here goes:

Periodically (less than 1-3 times per day on avg I think) my scanner will play audio from a talkgroup which is not programmed or at least not being scanned.. For instance I'll be scanning and it will stop on a police talkgroup and I'll hear audio from say EHS or a garbage company. To put it more simply, I don't even need to be scanning for this to happen, I could be paused/stopped on a talkgroup, and I'll hear someone else on our trunking system key up and transmit. This always coincides with traffic on the talkgroup I have scanned to and stopped on. It's like two users are keying up at the same time, and my scanner is choosing the wrong voice channel to play out the speaker. I've never heard a user comment when this happens so it may be on my end. Does this make sense, and if so, does anyone have any thoughts on a fix? Thanks.

 

[ScannerSK]

I experience this once in a while on my PSR-500; this occurred even more frequently on the PRO-96. It typically occurs only when a system is very busy and has to do with the scanner continuing to decode conversation on a specific voice frequency in error after the conversation has ended or moved to another voice channel. When voice frequencies are being rapidly reassigned to new conversations due to system load is when this typically begins to be noticed.

There may be an "advanced" setting in the PSR-500 for some systems which relates to how quickly the scanner checks the control channel after a conversation has ended on a voice channel?

Shawn

 

[darrylcn]

Ahh ok. Thanks! It's more typical on the busier towers here so I bet that's it. Thank you.

 

[ScannerSK]

You're welcome...

For P-25 systems you could try lowering the value of the following:
96VC SQ TO
96VC XF TO

For Motorola systems you could try lowering the value of the following:
EndtoneMot

For EDACS systems you could try lowering the value of the following:
EndtoneEDACS
EDACS ET HO

Shawn

 

[darrylcn]

I'll do that. We're (for a little longer) on Moto 800. Should have mentioned that before. Appreciate the fast help.

 

[RKG]

As a guess, the issue in question involves the two ways in which Motorola SmartNet/SmartZone sysems handle what happens when a subscriber unkeys, which is a question of system programming.

For "Message Trunking," the system keeps the voice channel assignment up for a hang time, so that prompt responders can access without a new ISW/OSW sequence. This also allows one subscriber to key up and talk over another subscriber who is already talking (called "barge in").

"PTT-ID Trunking" works the same way, except that each time a successive subscriber keys, his radio briefly switches to the control channel to send his ID, then reverts back to the original voice channel. This enables the system to keep track of who is talking after the first guy.


For "Transmission Trunking," the system takes down the voice channel assignment immediately upon receipt of the turn-off tone by a subscriber, and sucessors have to make a new ISW/OSW sequence in order to gain access to a voice channel, which may not be the same as the one in use a second ago. Barge ins don't work, because any time a subscriber keys his radio programmed for Transmission Trunking, it sends an ISW on the control channel.

While I've never pursued the issue with the PSR-500 or Win500, I did notice early on that there was no user programmable parameter for trunking format. So how these radios handle the difference between the formats is a bit of a mystery (to me at least).

I suspect (really a guess) that your PSR is hanging on to the voice channel while you are listening to a system programmed for Transmission Trunking, and what you are hearing is some other talkgroup using that voice channel under a new OSW assignment.

All of this is limited to SmartNet/SmartZone systems. Astro25 systems use PTT-ID Trunking by unalterable default.

 

[Daleb49]

I have a question also on a PSR-500.
What would be a recommended Dwell setting on TSYS objects tab.
Thanks

 

[SCPD]

I have a question also on a PSR-500.
What would be a recommended Dwell setting on TSYS objects tab.
Thanks

If that is CC Dwell time, all my systems are set at 0 and I have never had issues with my PSR500.

 

[Daleb49]

It's the setting on win 500 on the TSYS tab under your trunk group settings lists.

 

[kscott]

I have a question also on a PSR-500.
What would be a recommended Dwell setting on TSYS objects tab.
Thanks

I have found "3" to work well. Quick scanning in multisite mode, but long enough not to miss transmissions.

 

[Daleb49]

Thanks I'll try that.