MPSCS Question

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First of all, it's good to be back! I recently moved to the west side north of Grand Rapids and I finally broke out my old BC796D for the first time in a LONG TIME. I am working on programming it up for my new area.

This is probably a stupid question, but here it goes -- Regarding the statewide MPSCS system. Since it is a statewide system, we have all these hundreds and hundreds of talk groups for the entire system broken down by county, organizations or whatever. We also have many towers all over the state. My question is, what decides which tower gets to transmit what talkgroups?

For example, I am living in Rockford and am monitoring the Cannonsburg tower pretty well. I have been getting crosstalk tonight from MSP region 5 and region 6 which makes sense. My question is, since it is a system that spans the entire state, what decides that the towers local to me do not transmit talk groups not in my geographical area?

With so many hundreds of talk groups how do you really know which ones you could potentially get? It seems like with a statewide system, what talk groups go out which towers has to be decided somehow right? Is there a way to know what talkgroups are authorized to go out what towers? Thanks!
 

krokus

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For a TG to be carried on a specific tower, that TG has to be authorized on that tower, and there has to be a valid user affiliated with that tower and TG.

For instance, a Washtenaw County user, that has a regular county TG selected, and is in Alpena, will not get any traffic, nor be able to transmit on that TG. (Most of Washtenaw's TGs are only authorized on the towers in the county, and one ring of towers around the county. That allows for affiliation with towers outside of the county, when they are closer and/or have stronger signal, while maintaining communications.)

Another example, Detroit has moved over to MPSCS for police, fire and EMS, but most of their TGs are only authorized on the Detroit towers. (They might be authorized on the Wayne County towers, I have not heard a definitive answer on that topic.)

[begin added text]

Just for clarification: A scanner user can scan any TG they want, but will not hear any traffic that is not for an authorized user. That means that a scanner in Marquette, that is listening for Monroe County's fire dispatch, will probably never hear it.

I have set up someone's scanner, who lives in Livingston County, but within the service area of a Washtenaw tower, and they want to scan both counties. I set up two separate entries for MPSCS, one for each county. I then set up a scan list for each county, and each of those scan lists calls up the MPSCS system entry for that county. This will seem redundant, but was the only way to be sure to receive all radio traffic in the respective county.
 
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Thank you much! Maybe it is just the new area, but it seems like the MPSCS has definitely improved dramatically since the last time I was actively monitoring it!! Having a lot of fun with MSP Region 6 dispatch up here and comes in real clear!

I did notice that if I leave it on ID Search, I get some "interesting" talk groups that are designated for counties nowhere near here though. Normal?
 

rdale

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Just means someone from that county happens to be driving through your area with his radio on.
 
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Just means someone from that county happens to be driving through your area with his radio on.

I don't understand that. The first response to the thread indicated that talk groups were only permitted on the towers that were local to their geographical area in general.

So, if the guy is from 6 counties north of here and is driving through town, his local talk group shouldn't work. Am I misunderstanding something?
 

mikey60

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Joey,

Some talkgroups are restricted to specific tower sites, others are not. I've heard talkgroups from all over the state in the Detroit area. It all depends on where the radio users are and if the talkgroup they have on is allowed in that area.

Mike
 

SCPD

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Well

I don't understand that. The first response to the thread indicated that talk groups were only permitted on the towers that were local to their geographical area in general.

So, if the guy is from 6 counties north of here and is driving through town, his local talk group shouldn't work. Am I misunderstanding something?

There IS something in the statewide system that will let a user that's far from home talk back to his "home" towers. I have noticed that when Downriver or Detroit goes up north or to the west side of the state, peope will post on here that they were on their towers while passing thru.. I don't know if this is something set up ahead of time, or if the system just recognizes the radio, automatically knows what system that radio needs to be listening to, and route the calls thru the backbone back to and from that radio and it's home system.
 

rdale

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Many talkgroups like local fireground, police TAC, etc are NOT statewide. Others allow their dispatch TG to go everywhere. I go on vacation to Otsego Lake every summer, and every time I'm there the first few days I can hear Livingston PD dispatch. When a firefighter from Monroe County comes to Lansing for training, I hear their FD dispatch only on the local tower.
 

Skud

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I read in one of the papers and i think it was in the training manual that when they leave their area they are suppose to use statewide talkgroups and not scan. I know most don't. Look what happened when everyone came to GR and the site when down because so many people were still scanning :)
 

ffexpCP

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MPSCS radios set to scan will not cause system issues. A scanlist on a MPSCS radio will not turn on talkgroups on a tower. The radio will only 'turn on' one TG on a tower.

But all those individual TGs on individual radios can add up, overwhelming the trunk.
 
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Many talkgroups like local fireground, police TAC, etc are NOT statewide. Others allow their dispatch TG to go everywhere. I go on vacation to Otsego Lake every summer, and every time I'm there the first few days I can hear Livingston PD dispatch. When a firefighter from Monroe County comes to Lansing for training, I hear their FD dispatch only on the local tower.
Agreed I can hear Livingston very well here sometimes.
 

drdispatch

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When we took our MPSCS training in 2006, our instructor told us that officially, local talkgroups were only valid within your county or in the immediate vicinity, depending on where the nearest towers were located. Otherwise, if somebody took their radio on vacation up north, & turned on their home TG, the system would deliver all traffic on that TG to the site to which that radio was affiliated, thereby taxing MPSCS resources unneccesarily, & possibly causing local users to get "bonked". But, "unofficially", that particular restriction had been disabled, so it was possible to listen to your home talkgroup on the other side of the state (One of our officers reported listening to our traffic while on vacation in the U.P.). The powers-that-be at MPSCS had threatened to turn that restriction on again, & have been saying that for years, but I don't think they ever made good on that threat. If the police chief''s convention in Grand Rapids a while back didn't drive home the point, I don't know what would.

And remember that if you are just monitoring 1 tower, you may miss traffic on TG's that you have programmed if there is no radio on that TG affilliated with the tower you are listening to, particularly if your county's towers are at opposite ends of the county.
 

rdale

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And by "home" it means primary... If the Monroe Co firefighter in Lansing turns his radio to a fireground channel he won't hear it.
 
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