Cannot get trunking priority scan to work.

[Anderegg]

I enabled priority on the system as well as a specific talkgroup, but when I am scanning, the priorty never works. I remember giving up on figuring this out on my 996's, I have Motorola for priority scan, but I am replacing a Motorola with an SDS200, so I need to figure this out now.

Paul

 

[GTR8000]

What is the system type? If P25, are these exclusively TDMA talkgroups you're having trouble with? If yes, then you're out of luck. Uniden never properly implemented Priority ID Scan with P25 TDMA talkgroups on any of their Phase II capable scanners.

 

[Anderegg]

3600 baud analog Smartzone, as well as 9600 baud Phase 1...both programmed single site. They continue to listen to other things while I hear the Pri talkgroup on another scanner. The P is displayed on the talkgroup whenever it does randomly scan to it.

Paul

 

[GTR8000]

To be clear, Priority ID Scan on trunked systems only applies within the same system while scanning. In other words, if the scanner is stopped for activity on a talkgroup of the 3600 system, it will not preempt for a talkgroup flagged as priority on the 9600 system, and vice versa.

 

[Anderegg]

Understood, both systems are the old and new SD City Fire Dept systems, both set to Pi on the dispatch talkgroup, so whatever it is hearing, it will always have a same system priority that it is not reverting to.

Paul

 

[ofd8001]

Saying what GTR8000 differently, Uniden scanners do NOT pre-empt ongoing transmissions to check for activity on a priority talkgroup. Only when the scanner is monitoring/listening to the control channel does the priority ID "thing" work.

(Only certain types of systems is there "true" priority scanning on trunked systems and those are few and far between. Then some other things are needed. I mention this only to keep from getting "dinged" by the purists).

Priority scanning on a trunked system is a whole different thing than priority scanning on a conventional system. You aren't doing anything wrong, this is just how the scanners work. (Yeah I wish it was different too).

 

[Anderegg]

I can litterally HEAR the subaudible control channel during voice traffic on the 3600 analog system. I was under the impression that trunked systems spat out subaudible or encoded data (for digital talkgroups) on the voice channels that are used to signal things such as priority among other features. I seem to remember reading an explaination of how the hex system works and why talkgroups only come in certain numbers and that is used to reduce CC data for priority and such.

Paul

 

[GTR8000]

Yes, 3600 and 9600 systems both broadcast low speed data on the traffic channels. This is precisely how subscriber radios monitoring an active voice transmission on a traffic channel are able to be aware of other voice transmissions on the system, and can switch to those talkgroups if they are setup as priority talkgroups.

PS - Having priority function only when the scanner is on the control channel makes absolutely no sense, as it is seeing all of the grants anyway and would switch to the first talkgroup that becomes active, regardless of priority. The entire point of having priority setup is so that the scanner would be able to switch to that priority talkgroup while it's monitoring an active voice transmission on a non-priority talkgroup.

 

[ofd8001]

PS - Having priority function only when the scanner is on the control channel makes absolutely no sense, as it is seeing all of the grants anyway and would switch to the first talkgroup that becomes active, regardless of priority. The entire point of having priority setup is so that the scanner would be able to switch to that priority talkgroup while it's monitoring an active voice transmission on a non-priority talkgroup.

You would think/hope so, but the way Uniden scanners work is that checking for traffic on priority talkgroups only happens when the scanner is "idle" (monitoring control channel). This concept is common to all recent (at least) Uniden scanners. The only sort of helpful priority is in this scenario: You are holding on Channel A, a non-priority talkgroup and there are no conversations on this TG. You have Channel X set as a priority talkgroup. Should Channel X become active, the scanner will jump from Channel A to Channel X and begin hearing the conversation.

I'm not defending this method - I really wish it was a "true priority" type scanning method. Most likely there is a very good reason why the situation is what it is, but it might be either engineering or business based and Uniden might not be offering up trade secrets.

 

[GTR8000]

Most likely there is a very good reason why the situation is what it is.

Doubtful, as the current iteration of Priority ID Scan is mostly pointless given the inherent limitation, and certainly nowhere on par with how a subscriber radio works. Pretty silly, given that the low speed data announcing active calls on the traffic channels is readily available for P25 systems. If the Uniden engineers were able to figure out how to get the subscriber ID from that traffic channel data, they could certainly figure out how to get the call grants and updates from the same data stream; they simply chose not to for whatever asinine reason, thus rendering "Priority" nearly useless on trunked systems.

 

[Anderegg]

Oh well...I remembered there was a reason I gave up on 996 trunked priority...I believe this was it.

Paul

 

[palmerjrusa]

Am I mistaken here?
I monitor a P25 system on my SDS100/200, have enabled priority scanning for the system and have tagged priority channels.
When I'm listening to a non-P tagged channel, if one of my tagged P channels becomes active it switches to that channel even though there's still conversation on the non-P channel.
At least I'm assuming that's what it does.

 

[Anderegg]

I am performing a system search on my P25 system with a 255 second hold time set...I will give it an hour of FD dispatches to see if Prio works in any way...the garbage trucks here tie up the 700MHz P25 system like they are bored HAM radio operators.

Paul

 

[ofd8001]

Am I mistaken here?
I monitor a P25 system on my SDS100/200, have enabled priority scanning for the system and have tagged priority channels.
When I'm listening to a non-P tagged channel, if one of my tagged P channels becomes active it switches to that channel even though there's still conversation on the non-P channel.
At least I'm assuming that's what it does.

Is that a conventional or trunked system? What you mention is correct on Conventional systems, but not Trunked.

Here is what the manual says on trunked Priority ID scanning:

Priority ID Scan – This function is similar to conventional priority although there is no interruption
during the transmission. Priority is checked in between transmissions, when the scanner is
receiving the control channel, and during the channel delay period. The scanner can only look for
priority IDs in the trunked system it is currently scanning.

 

[Anderegg]

Yeah, I only want it to revert to the priorty talkgroup, if it never receives the priority talkgroup unless it is not receiving anything else, that is just normal sacnning...am I wrong? If the scanner is not receing other active talkgroups, meaning they are not active, then if the priority talkgroup talks, it will be received, not because of any priority, but simply due to lack of any other transmissions taking place at that tiume, indicated by the fact the scanner was scanning.

Paul

 

[palmerjrusa]

Is that a conventional or trunked system? What you mention is correct on Conventional systems, but not Trunked.

Here is what the manual says on trunked Priority ID scanning:

Priority ID Scan – This function is similar to conventional priority although there is no interruption
during the transmission. Priority is checked in between transmissions, when the scanner is
receiving the control channel, and during the channel delay period. The scanner can only look for
priority IDs in the trunked system it is currently scanning.

I checked this again.
It's a P25 trunked system.
Yep, I thought it was going to a P-tagged channel while I was holding on a channel but it appears it's going to the P-tagged channel during a break in the transmission on the channel I'm holding on.

 

[ofd8001]

The priority "thing" is kind of wild. You can be on an idle talkgroup in a trunked system and have a priority frequency set for a conventional system. The scanner will jump from the trunked TG to check for traffic on the conventional system priority frequency, but not vice versa.

Again I'm sure there is a method to Uniden's madness on this.

 

[Ubbe]

You can be on an idle talkgroup in a trunked system and have a priority frequency set for a conventional system.

Is that still working? It could have been part of the "house keeping" that dropped the control channel for a brief moment but "house keeping" have now been removed from the firmware?

/Ubbe

 

[buddrousa]

Doubtful, as the current iteration of Priority ID Scan is mostly pointless given the inherent limitation, and certainly nowhere on par with how a subscriber radio works. Pretty silly, given that the low speed data announcing active calls on the traffic channels is readily available for P25 systems. If the Uniden engineers were able to figure out how to get the subscriber ID from that traffic channel data, they could certainly figure out how to get the call grants and updates from the same data stream; they simply chose not to for whatever asinine reason, thus rendering "Priority" nearly useless on trunked systems.

Yes but a subscriber radio will not scan conventional channels and trunking channels at the same time.

 

[GTR8000]

Yes but a subscriber radio will not scan conventional channels and trunking channels at the same time.

Where did you get that idea? It's not correct. Motorola radios have allowed mixing conventional and trunking in the same scan list for many years.

XTS/XTL Scan Type - Talkgroup

• Both Conventional and Trunking Scan List member channels may be selected.

APX Scan Type - Multi-System Talkgroup

• Both Conventional and Trunking channels may be selected for this Scan List type.
• Per Scan List, Multi-System Talkgroup Scan is limited to five (5) Trunking Systems, with up to fifty (50) Scan List Member channels per Trunking System, and may include up to ten (10) Conventional Scan List Member channels. However, the maximum per Scan List is 250 Scan List Member channels.

APX Scan Type - Intelligent Priority

• Both Conventional and Trunking channels may be selected for this Scan List type..
• This scan type is based upon Multi-system Talkgroup Scan, supporting the limits of that scan type. This scan type provides the ability to configure a Priority 1 and Priority 2 scan member.