CSP Multi Site Links

[dimab]

How is the CSP multi site system linked?

If I listen to the Litchfiel County (N or S) site(s), I can still hear Troop H and others from those control channels. This is vice versa also with the Bristol Site, I can hear other Troops that aren't part of that site coverage.
So, are the sites linked via DSL lines, or some type of microwave signals?

Maybe I'm not understanding the whole scope of how multi site system works, but I thought that what ever site you're in, your radio is programmed for those control channels only, and thats the site you can only TX/RX on. This is why my question came up about RX signals from other sites coverage areas.

 

[seamusg]

How is the CSP multi site system linked?

If I listen to the Litchfiel County (N or S) site(s), I can still hear Troop H and others from those control channels. This is vice versa also with the Bristol Site, I can hear other Troops that aren't part of that site coverage.
So, are the sites linked via DSL lines, or some type of microwave signals?

Maybe I'm not understanding the whole scope of how multi site system works, but I thought that what ever site you're in, your radio is programmed for those control channels only, and thats the site you can only TX/RX on. This is why my question came up about RX signals from other sites coverage areas.

Most system like this are linked by Microwave, but can be linked by T1's. Each tower advertises it's neighbors and their control channel. When a radio loses the control channel it looks for another one based on the information it has (system ID has to match). The control channel tells the radio what freq to transmit and receive on. Also DLS would be too slow to carry the traffic between sites, T1 would be the slowest to use that would work. When Motorola Demoed the Macomb simulcast system to the Macomb Co., MI people they linked it to the MPSCS system with a T4. Michigan uses all microwave to link their towers and link back to the central control center.

 

[cg]

When the smartzone system was set up, someone in CSP decided which talkgroups needed to be heard where. For example, Statewide 1 needs to be available everywhere whereas Eastern District Traffic pertains only to a limited part of the state. The main computer is then programmed as to where to allow which talkgroups. So, why then do you not hear all the allowed talkgroups on all the allowed sites 24/7?? ...

Affiliating is a process where a radio automatically attempts to "sign on" with a certain zone. It could be because the operator changed talkgroups or he entered another area. If the talkgroup that the radio is on is allowed to be broadcast in that zone, the system will then rebroadcast that talkgroup on the zone. Essentially, it is like walking through a house with motion detectors on the lights. As you go from room to room, the lights go on. When you leave the lights go off. If there are other people in other rooms, the lights will be on there as well.

Many talkgroups are heard all the time on some zones just because there are always at least one radio affiliated to it.

I think the first reply (or I) misunderstood the question. The method for getting the signals to the remote sites has nothing to do with what talkgroups are being rebroadcast on each site.

cg

 

[PJH]

The system itself is pretty much all microwave thru the Connecticut CTS backbone.

Systemwide talkgroups are rarely "always on" and that's primarly for system/site loading. Why statewide one is left open, I am not sure. Unless something changed not too long ago, CSP radios were not setup to scan talkgroups (both portable and mobile) so it pretty much makes systemwide use, well, useless.

I am sure there was a good reason on Day 1, but things change all the time.

But to over simplify the system, any and all talkgroups that a radio has affliated to any site or zone will be heard. For instance...if all the Troop A troopers are in troop A terriorty, and one of them goes to troop C land, and keeps the radio on the Troop A channel, you will hear Troop A radio traffic in the Troop C zone. This traffic will follow the radio as they move around. Pretty much it works like a cell phone as sites/zones hand traffic off to each other.

 

[PJH]

Also, try this site. It may or may not help

http://www.thebriarpatch.org/trunking/system_types.html

 

[KB1JHU]

But to over simplify the system, any and all talkgroups that a radio has affliated to any site or zone will be heard. For instance...if all the Troop A troopers are in troop A terriorty, and one of them goes to troop C land, and keeps the radio on the Troop A channel, you will hear Troop A radio traffic in the Troop C zone. This traffic will follow the radio as they move around. Pretty much it works like a cell phone as sites/zones hand traffic off to each other.

Just to add a bit to that. Most, if not all, DEP Environmental Conservation Police Officers have a CSP radio in their vehicle. If they are driving around and playing with the radio, you may get the same effect, hearing troops from one side of the state in a zone at the other. Not absolutely sure on that, I guess it depends how the CSP radios the EnCon Officers have are set up. On a side note, has anyone ever heard an EnCon officer talk on the CSP system? I have yet to spend the money on a digital scanner, so I can't listen yet. Then again, if I pass the protective services physical fitness test (already did the written, got an 89) I may be an EnCon trainee by next year and eventually have access to the system and won't need the scanner.

 

[PJH]

Almost forgot, since you touched upon it..

Since scan isn't (again, unless its recently changed) a common practice for troopers is to have the vehicle radio on their troop channel, and the portable on the talkgroup in which they want to monitor. Since each radio in the system has its own ID, it doesn't bump the radios off the system (security feature). Now you have another talkgroup in a zone that may not normally be there.

This practice is discouraged since one may forget their portable may not be on their troop channel, and if you go running after someone at a moments notice...

 

[kmacinct]

DEP Officer aka EnCon

Around troop K, we have a few DEP officers that occassionally work on the troop system and can be heard.

DEP Officers have a 3 digit ID number ,to talk to their main office "CO" on the 44.xxmhz channels.

In order to not conflict with CSP id numbers, they add a another digit to the beginning of their radio number..

ex: DEP Officer "635" on the 44.xx freq would be "6635" on the CSP System.

Kevin