PSR-600 Missing Transmissions?

[fmulder13]

Hi all,

At the moment my PSR-600 is set up to scan two lists, each containing primary dispatch and a couple special car-car channels for one agency each, each agency tied to the same site of a statewide multi-site Motorola analog system. (It's the Oklahoma DPS system, Norman site, and I'm scanning OU PD and Norman PD in their own respective lists.) I'm finding that, while in scan mode, transmissions from Norman PD are being missed. Norman PD's dispatch channel is set as a PRI channel, PRI is enabled, but during scanning I'll either hear only a reply to a question I never heard, or I'll hear one side of a conversation. This phenomenon disappears completely when I put the scanner into MAN mode on Norman PD, or when I have OUPD and Norman PD as my only two favorites. I'm also pretty sure that this never occurs on the OUPD channel, that the scanner will fail to interrupt OUPD for Norman PD while in scan mode, and that this is a new phenomenon since Norman PD recently began using a new talkgroup for their dispatch channel. Any suggestions?

 

[SkipSanders]

Unless this scanner is something very unique, no trunking scanner can 'interrupt' a currently active voice talkgroup to switch to another talk group that's become active... because it's not listening to the control channel while it monitors the 'active' talk group.

One receiver. It sits on the control channel, till it picks up an 'I want to hear this' talkgroup active. It then switches the receiver to that talkgroup's designated current frequency, and sits there till carrier drops, or a 'close channel' type of short digital message is received there.

It's not listening to the control channel, so it doesn't know another group has become active till it drops off the active talkgroup for a moment.

The only way you can do this 'talkgroup priority' game is two receivers, one monitoring the control channel, and one being directed by the software monitoring the control channel to follow talkgroup channels. (Unitrunker can do this)

'Priority' for a single receiver trunking scanner means that when it drops off a talkgroup, it will THEN go to the 'priority' talkgroup if it's active, in favor of picking up the next transmission on the previous talkgroup.

 

[fmulder13]

I see your point, but I can assure you that I have seen PRI interrupts on this system. When I have the two channels I mentioned in my FAV list, I had Norman PD repeatedly interrupt OUPD. A screen message that basically says "PRI Interrupt" flashes briefly, and the scanner switches to the PRI channel.

 

[ibagli]

Unless this scanner is something very unique, no trunking scanner can 'interrupt' a currently active voice talkgroup to switch to another talk group that's become active... because it's not listening to the control channel while it monitors the 'active' talk group.

Several scanners do it through listening to the subaudible data on voice channels to monitor for other talkgroups, if it's enabled on the system (it's only done on Type II systems, as far as I know).

 

[DonS]

Unless this scanner is something very unique, no trunking scanner can 'interrupt' a currently active voice talkgroup to switch to another talk group that's become active... because it's not listening to the control channel while it monitors the 'active' talk group.

One receiver. It sits on the control channel, till it picks up an 'I want to hear this' talkgroup active. It then switches the receiver to that talkgroup's designated current frequency, and sits there till carrier drops, or a 'close channel' type of short digital message is received there.

It's not listening to the control channel, so it doesn't know another group has become active till it drops off the active talkgroup for a moment.

The only way you can do this 'talkgroup priority' game is two receivers, one monitoring the control channel, and one being directed by the software monitoring the control channel to follow talkgroup channels. (Unitrunker can do this)

'Priority' for a single receiver trunking scanner means that when it drops off a talkgroup, it will THEN go to the 'priority' talkgroup if it's active, in favor of picking up the next transmission on the previous talkgroup.

Of course, if the voice channel carries the info, and if the scanner can decode it, then such "priority talkgroups" are surely possible.

The PSR-500 family (which includes the PSR-600) can get priority talkgroup info from "voice channels" on Motorola (EDIT: analog voice) and LTR systems. Actual performance will vary depending on the specific systems and talkgroups programmed into the scanner... Mot systems must be configured to send the TG info out on the voice channels. LTR needs no such configuration, but the possible "priority" talkgroups are limited to those "homed" to the current repeater.

 

[fmulder13]

That having been said, any idea where my problem lies? Too many objects scanning at once? Adjustments needed on the SQ Int. Time? Something I've done wrong in programming? Thanks much!

 

[DaveIN]

I see your point, but I can assure you that I have seen PRI interrupts on this system. When I have the two channels I mentioned in my FAV list, I had Norman PD repeatedly interrupt OUPD. A screen message that basically says "PRI Interrupt" flashes briefly, and the scanner switches to the PRI channel.

Interesting and good to hear that it works in PRI Interrupt mode. I had not seen a Motorola system with this feature yet.

I wonder if you put the two agencies in different but copied TSYS, and then in two different scanlists, to separate them if it would still occur? You could do this with the software.