VHF Patch Traffic

[gg750]

In Michigan here, with a question about the digital P25 statewide system. This may get a little confusing, so I'll try to keep it as simple as possible.

Here in Grand Traverse county, Central dispatch has a VHF patch and a talkgroup ID on the MPSCS, Michigan's statewide TRS. The county I am in has not joined the statewide system yet, but all MSP are on the system, and we have an MSP post in the county that often communicates with Central Dispatch.

Several months ago, I used to be able to hear all VHF-patched traffic from central on the GT county talkgroup (this included dispatchers, sheriff's department mobile and portable radios, and of course, MSP using the VHF patch to talk back to central).

Now, things have gotten a little weird. I'll try to explain...

If I'm listening to central on the countys analog frequency, I can hear all radio traffic EXCEPT MSP units talking to central using the VHF patch.

If I'm listening to central on the digital system, I can hear central and MSP, but I CANNOT hear any sheriff mobile/portable radios talking back.

Does anyone know what would have caused the traffic to be cut out in this way? It's really odd. Even Deps. on the road say they cannot hear MSP, and MSP say they cannot hear Deps.

Hope this makes sense to anyone reading it! And thanks for any input.

G

 

[greenthumb]

Does this describe what you are hearing:

*800 MHz portable and mobiles do not go through to VHF.
*VHF portable and mobiles do not go through to 800 MHz.
*Consoles make it through on 800 MHz and VHF all of the time (you hear VHF dispatching on 800 MHz all of the time).

If this is the case, I would say that the talk groups probably aren't patched anymore, rather they are multi-selected by the console, hence the reason you can hear the dispatch console on both bands, but portable and mobile radios stay on their own respective band.

 

[gg750]

Thats it exactly.

I would think that they would have kept the patch. The county deps and local state troopers work together so often that not being able to talk to each other without having to relay through central would be a safty problem during a major emergency.

G

 

[wavetar]

Thats it exactly.

I would think that they would have kept the patch. The county deps and local state troopers work together so often that not being able to talk to each other without having to relay through central would be a safty problem during a major emergency.

G

They likely will set-up a patch during any emergencies...just that for the regular day-to-day stuff, the departments really don't need to hear each other's business. It's a quick drag & drop change for Centracom Elite dispatching systems & I'm assuming just as easy for Zetron/Orbacomm based systems. This is the way I've seen it done many times.

Todd