SDS200 - Priority channel

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ansky

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I need clarification on how the priority channels work. Let's say I'm scanning through 3 favorites lists (FL1, FL2, FL3). If I set one of the channels in FL1 as a priority channel, and I'm stopped on a channel in FL2, will the system switch over to that priority channel even though it's assigned in a different favorites list?
 

osiris

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HI ansky, the only way it will switch to a priority channel is if you are holding on a channel in one favorites list and the priority channel is an analog channel in another favorites list. The radio won't switch from one trunked system to another trunked system too access a priority channel in that favorites list. Hope that answers your question. At least that's what I have found.
Bob
 

ofd8001

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Let me explain this a different way. Trunked priority scanning is different from conventional priority scanning. It doesn't matter whether it is analog or digital.

With a conventional system, this is called "Priority Scan Mode". When the scanner is stopped on a non-priority channel, it will briefly look at all channels marked as Priority to see if there is traffic. If so, then the scanner remains on the priority channel. (This is called "Pre-emptive"). It does not matter where the priority channel is - it could be in the current Favorites List or another Favorites List. (I think that all active Favorites Lists are loaded in the active memory).

On a trunked system, this would be called "Priority ID Scan". When the scanned is monitoring the control channel, it will give priority to a talkgroup that is marked as a priority channel. By that I mean two channel grants happen at once - the scanner would choose the one that is marked as priority. For most trunked systems, there is no such thing as pre-emption of ongoing communications to check for traffic on a priority talkgroup. Not exactly what we would think as priority scanning, then but that's the way these scanners have been for years, going back to the x96 models at least.

An interesting quirk I've seen - depending on which Priority Scan Mode is chosen, I've seen the scanner pre-empt an on going trunked system conversation to check for a priority transmission on a conventional system. However, the reverse is not true, since there is no trunked pre-emption generally.

(As always there are exceptions. Motorola Type 2 trunked systems do allow for pre-emption, but only as designed by the system administrator and not by the scanner. The priority talkgroups are those identified as such by the system managers and not the scanner programmer.)
 
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