Woahhh TRUNKING!

[carrie640]

Wow! I am truly "behind" the times. I worked in law-enforcement in various capacities and the last thing that I ever wanted to do was listen to a scanner when I wasn't working.

With the wake of this blizzard stuff going on, I thought I would dig my handheld out. I changed the dead batteries (Sucker was still programmed, surprisingly) but was quite surprised when nothing was happening.
I thought the frequencies changed, but in my searches, I see this new TRUNKING stuff. UGH.

Yeah. Not-so-fun to be me right now. I've got the old-school (I bought it new back when, though!) Pro-50 from Radio Shack!! LOL

I read the wiki-stuff on this, but am still a little confused and before I go out and invest in anything new, I need to try and get some more information.

I am in Ingham County (Michigan). More specifically, I am in the city of Lansing. Way back when, we had like 3 frequencies: 1 for the north end. 1 for the south. 1 for LEIN..and probably at least another for car to car.

There was a frequency for out-county (Sheriff Department). There was one for East Lansing. There was one for Meridian Township. Then each fire jurisdiction had one. It was nice because if I just wanted to listen to the north end (where I am), I could. I didn't have to try and filter out other areas.

I have the scanner app for Android that I believe is streamed from this website. But, the BIG issue I have with it is that EVERY STINKIN' JURISDICTION in this COUNTY is on it. I can't keep straight who is who! It moves WAY too fast and I don't want to hear what is going on in East Lansing...or Meridian Township....or the south end, etc. I just want to hear what is going on WHERE I AM.

With that in mind, if I invest in a scanner that is compatible with this new system (I've read that the jurisdictions here are all on this 800mhz trunk system...EDACS or something?), am I going to get the same cluster-f*** of radio traffic? Am I going to really hear MTPD, ELPD, ICSD on top of Lansing (north south east and west??) or will there still be separate frequencies for these departments? If it is going to be like 6+ departments on one channel, I might as well just do the Droid app. But if I can program EACH department, I will invest in the scanner.

Thanks in advance for the information! The older I get, the more challenged I become with this technical stuff!!! ~

 

[EP204]

I am in Ingham County (Michigan). More specifically, I am in the city of Lansing.

With that in mind, if I invest in a scanner that is compatible with this new system (I've read that the jurisdictions here are all on this 800mhz trunk system...EDACS or something?), am I going to get the same cluster-f*** of radio traffic? Am I going to really hear MTPD, ELPD, ICSD on top of Lansing (north south east and west??) or will there still be separate frequencies for these departments? If it is going to be like 6+ departments on one channel, I might as well just do the Droid app. But if I can program EACH department, I will invest in the scanner.

Thanks in advance for the information! The older I get, the more challenged I become with this technical stuff!!! ~

Try also asking in your local forum, (http://forums.radioreference.com/michigan-radio-discussion-forum/) with trucking each talk group (TG) is separate, like the freqs use to be, each one a channel, for most systems. Type 1 systems are different, I do not know for your area, but I would guess that the north has one or two TGs or more, you can only scan those or you can add more TGs for more traffic, some for PD, fire, etc...
Hope this helps, and welcome to RR.
73s

 

[mtnmadman]

I feel your pain! Had scanners as a kid, Last one was a PRO 2050.. never could figure out the trunking, but the county had VHF simulcast channel, so no big deal. Then, they killed the simulcast freqs, so now i have been trying to figure this thing out! Im getteing there. Youre in the right place for help!!!

 

[Astrak]

With your own scanner you'll be able to listen to what you want to. If it's an EDACS system you'll probably be able to pick up an older scanner that does EDACS trunking for fairly cheap.

 

[OsloViking1975]

Michigan is mostly digital pretty much. But the Sheriff and Lansing PD uses EDAC Standard Provoice and Analog In Ingham County

http://www.radioreference.com/apps/db/?sid=2849 You should be still able to listen to them with a good scanner that does EDAC.

Sheriff's Department Talkgroups

DEC AFS Mode Alpha Tag Description Tag
275 02-023 A LEIN LEIN for all agencies except EL, MSU, Meridian Law Talk
289 02-041 A IC MAIN Dispatch Law Dispatch
290 02-042 A IC TAC Tactical Law Tac
291 02-043 A IC TRNG Training Law Talk
292 02-044 A ICEVENT1 Event 1 Law Tac
293 02-045 A ICCAR Car-to-Car Law Talk
294 02-046 A IC CMND Command Law Tac
295 02-047 A IC PARKS SO Parks Dept Law Talk
296 02-050 A IC COURT SO Court Officers Law Talk
297 02-051 A AC TAC1 Animal Control Tac 1 Law Talk
298 02-052 A AC TAC2 Animal Control Tac 2 Law Talk
299 02-053 A PKEVENT1 Parks Dept Event 1 Law Talk
300 02-054 A PKEVENT2 Parks Dept Event 2 Law Talk
393 03-011 E IC DB Detectives (ProVoice only) Law Talk
394 03-012 E IC DBTAC Detectives Tac (ProVoice only) Law Talk
395 03-013 A ICDBCMND Detectives Command Law Talk
396 03-014 D IC ADMIN Admin (ProVoice only) Law Tac
401 03-021 A 33P911 Central 9-1-1 Police - Dispatch Law Dispatch


Lansing Police Department Talkgroups

DEC AFS Mode Alpha Tag Description Tag
273 02-021 A LA NORTH North Dispatch Law Dispatch
274 02-022 A LA N TAC North Tactical Law Tac
276 02-024 A LA S TAC South Tactical Law Tac
277 02-025 A LA SOUTH South Dispatch Law Dispatch
278 02-026 A LAEVENT1 Event 1 Law Tac
279 02-027 A LAEVENT2 Event 2 Law Tac
280 02-030 A LA DB Detectives Law Talk
281 02-031 A LA JAIL Jail Corrections
385 03-001 E LASTART1 START 1 (ProVoice Encrypted) Law Tac
386 03-002 E LASTART2 START 2 (ProVoice Encrypted) Law Tac
387 03-003 E LASOS1 Special Ops 1 (ProVoice Encrypted) Law Tac
388 03-004 E LASOS2 Special Ops 2 (ProVoice Encrypted) Law Tac
389 03-005 E LASOS3 Special Ops 3 (ProVoice Encrypted) Law Tac
390 03-006 A LA ADMIN Admin Law Tac
397 03-015 D LA CMND Command (Sergeants and above) (ProVoice Only) Law Tac
703 05-077 A LA SIMUL Simulcast - Bulletins/Urgent Information Law Dispatch

 

[fmon]

I feel your pain! Had scanners as a kid, Last one was a PRO 2050.. never could figure out the trunking, but the county had VHF simulcast channel, so no big deal. Then, they killed the simulcast freqs, so now i have been trying to figure this thing out! Im getteing there. Youre in the right place for help!!!

Click the programming shortcut link under my signature, The 2050 is listed with step by step programming.

 

[mtnmadman]

Thanks! lost the manual years ago, wife wants me to set it up for her...

 

[carrie640]

OK....see.....all of that below (except for the descriptors on what they are for ) is WAY over my head. What happened to the 460.100 type of stuff??? LOL!

Michigan is mostly digital pretty much. But the Sheriff and Lansing PD uses EDAC Standard Provoice and Analog In Ingham County

Ingham County Public Safety Trunking System, Lansing, Michigan - Scanner Frequencies You should be still able to listen to them with a good scanner that does EDAC.

Sheriff's Department Talkgroups

DEC AFS Mode Alpha Tag Description Tag
275 02-023 A LEIN LEIN for all agencies except EL, MSU, Meridian Law Talk
289 02-041 A IC MAIN Dispatch Law Dispatch
290 02-042 A IC TAC Tactical Law Tac
291 02-043 A IC TRNG Training Law Talk
292 02-044 A ICEVENT1 Event 1 Law Tac
293 02-045 A ICCAR Car-to-Car Law Talk
294 02-046 A IC CMND Command Law Tac
295 02-047 A IC PARKS SO Parks Dept Law Talk
296 02-050 A IC COURT SO Court Officers Law Talk
297 02-051 A AC TAC1 Animal Control Tac 1 Law Talk
298 02-052 A AC TAC2 Animal Control Tac 2 Law Talk
299 02-053 A PKEVENT1 Parks Dept Event 1 Law Talk
300 02-054 A PKEVENT2 Parks Dept Event 2 Law Talk
393 03-011 E IC DB Detectives (ProVoice only) Law Talk
394 03-012 E IC DBTAC Detectives Tac (ProVoice only) Law Talk
395 03-013 A ICDBCMND Detectives Command Law Talk
396 03-014 D IC ADMIN Admin (ProVoice only) Law Tac
401 03-021 A 33P911 Central 9-1-1 Police - Dispatch Law Dispatch


Lansing Police Department Talkgroups

DEC AFS Mode Alpha Tag Description Tag
273 02-021 A LA NORTH North Dispatch Law Dispatch
274 02-022 A LA N TAC North Tactical Law Tac
276 02-024 A LA S TAC South Tactical Law Tac
277 02-025 A LA SOUTH South Dispatch Law Dispatch
278 02-026 A LAEVENT1 Event 1 Law Tac
279 02-027 A LAEVENT2 Event 2 Law Tac
280 02-030 A LA DB Detectives Law Talk
281 02-031 A LA JAIL Jail Corrections
385 03-001 E LASTART1 START 1 (ProVoice Encrypted) Law Tac
386 03-002 E LASTART2 START 2 (ProVoice Encrypted) Law Tac
387 03-003 E LASOS1 Special Ops 1 (ProVoice Encrypted) Law Tac
388 03-004 E LASOS2 Special Ops 2 (ProVoice Encrypted) Law Tac
389 03-005 E LASOS3 Special Ops 3 (ProVoice Encrypted) Law Tac
390 03-006 A LA ADMIN Admin Law Tac
397 03-015 D LA CMND Command (Sergeants and above) (ProVoice Only) Law Tac
703 05-077 A LA SIMUL Simulcast - Bulletins/Urgent Information Law Dispatch

 

[mtnmadman]

hang in there

DONT give up..... took me a while to figure out the trunking.... now that i have (W/ help from the good people at RR) you Will get the hang of this.... loving my trunking scanner now. Just learned the trunking after having scanners since i was 5... (crystal units etc)))

 

[OsloViking1975]

I'm not familiar with EDAC systems I believe they use LCN (Logic Control NUmbers). Meaning each radio has to be programmed for a specific frequency.

This number here is a talkgroup# 02-021 LA NORTH North Dispatch Law Dispatch this is what you would program in your radioand would be able to hear that talkgroup.

 

[DickH]

I'm not familiar with EDAC systems I believe they use LCN (Logic Control NUmbers). Meaning each radio has to be programmed for a specific frequency. ...

If you're not familiar with EDACS, why would you even comment, let alone give out inaccurate information.?
LCN is Logical Channel Number. That means that each frequency MUST be in a specific channel in your scanner - and they might not be in numerical order. Some channels may be left empty, like 1, 4, 5, 6, 9, 12, 13, 15, etc. Also note the first freq. MUST be in channel 01, or 101 or 201. Channel zero is not used.

 

[OsloViking1975]

My mistake thanks for pointing that out. I feel much better now.

 

[BamaScan]

Sounds like You need a Uniden Home Patrol. It would be pre programed for you.

 

[Mike_G_D]

One way to picture how basic radio trunking works compared to a conventional system that you are familiar with is to liken them both to different ways to utilize roads for vehicular traffic.

Note - I know the road usage outlined here for analogy's sake isn't realistic (as far as using real roads in the real world is concerned) but it does help some who are non-technical and unfamiliar with trunking concepts picture such concepts better, in many cases.

Picture one system whereby a set of roads are available set up in such a way so that each road is dedicated to one specific type of usage, i.e. one for food delivery, one for building materials, one for auto parts, one to transport lawyers, one to transport auto mechanics, one to transport grocery clerks, etc. Now, each city, county, and state has its own set of these roads

In this system, a user who is only interested in following auto mechanics, for example, would only have to focus on the one road used to transport auto mechanics for that city/county/state, etc.

Normally in this system, users are assigned only to their specific roads and are not allowed to use other users' roads except under very special circumstances.

Such as system works fine as long as the number of vehicle user categories is low, traffic isn't too high, and you have A LOT of space for building lots of dedicated roads. It gets to be an issue, however, when you run out of space to make dedicated roads for every interested user, especially when the technology for building and issuing vehicles becomes cheap enough that more and more folks want to use vehicles for transportation of their specific goods, selves, and services.

From a vehicle user's standpoint in the real world one can see that dedicating specific roads for specific usages such as these on a permanent basis is an inefficient way to go. One obvious problem is that not all of the roads are being used all of the time at maximum traffic handling level. For example, you might see the lawyer road heavily used during the morning and evening commute hours but the rest of the day and the night it would be relatively deserted. However, since the road is dedicated to lawyer usage it can't normally be used by anyone else making it a useless wasted road for that part of the time (notwithstanding late night overtime lawyers, of course - for the sake of the analogy, let's say most are nine-to-fivers in this case). Folks such as the food delivery folks who might have a lot of traffic overnight could really benifit from using that road at night but cannot because they are not authorized to use that road.

So your "cons" for this system of vehicular road usage are:

1) Need for space to make roads dedicated to each specific user; keep in mind that each user might want more than one road for special circumstances too.

2) Not all roads are used to maximum capacity all of the time; that unused capacity cannot normally be used by users not normally assigned to those roads making it wasted capacity which could be otherwise usefull when some roads reach their traffic handling capacity limits.

The above system would be analogous to a conventional radio system wherein each frequency was specifically assigned to one type of user such as police, fire, city municiple, etc., and each city or county or state would then have its own set.

Wouldn't it be better to share one set of roads and simply select the one available to you that has the least traffic on it at the time you need it?

Now picture a system of roads wherein you have, say, only five roads but all are available to all users and simply selected as traffic loading allows. You could have twenty different types of users only using those five roads but because each user selects the road based on traffic usage and availability it works quite well most of the time. Yes, it can get congested under special circumstances but normally it allows a larger number of users to use efficiently a smaller number of roads far more efficiently than the dedicated road system. And, usually, adding one or two new roads to the shared road system adds far more to the that system's capacity than doing so would to the dedicated road system's capacity.

That's what trunking radio systems attempt to do with their frequencies. It takes a set of frequencies and shares those frequencies among many users.

It turns out that for radio systems, looking at the usage statistics for radio frequencies dedicated to single channels (conventional system) each frequency has a lot of "dead air" a lot of the time which could be put to use by other users.

In the most common types of trunking systems, some kind of central controller sets on a single frequency and all of the radios in the system monitor that frequency. These radios have little computers inside them which can understand and communicate with these controllers. They "speak" to each other in special "computer speak" and at very high speed (relative to our human mode of speech) and they (the central controller and the little computer in the user's radio in communication with each other) act as communication "traffic cops" which "guide" the radio user to the least used radio frequency at the time of need. Users are differentiated from each other by use of digital codes such that the user has a "channel" but that channel is no longer one dedicated radio frequency but is now a digital code known in radio trunking terminology as a "talk group". The central controller together with the little "brains" in each subscriber (system user) radio keep track of each other and "follow" the users as they travel around the system's coverage area. Anytime a user needs to communicate he/she simply selects the appropriate channel (trunking talk group) and presses the mic key as a conventional system user would do; however, in a trunking system's case, the channel is not a single frequency but a code that is understood by the central controller and, when picked up by the controller (as when a user presses the transmit key) the controller knows what group that user belongs to based on that channel/talk group selected by the user and then switches (through communication with the little computers within the users' radios) every other member of that group to the frequency it finds available at the time - this is known as an available "voice frequency" or "voice channel"; this initially takes place on the central controller's dedicated frequency (known as the "control frequency" or "control channel", which, in this case IS a dedicated radio frequency). All of this happens so fast that the users do not notice and, from a user's perspective, under normal conditions, they cannot tell any difference between this mode and having a standard conventional dedicated frequency.

Common types of systems that reflect the above are EDACS systems, "Motorola" systems, and variations of those two. One big difference between these two camps is how the control frequencies and voice frequencies are setup. For scanner users, EDACS systems require that you enter ALL of the system frequencies in a very specific order starting with channel one (no "zero") - this is known as the "Logical Channel Number" or "LCN" order whereas Motorola variants only need the control frequencies/channels entered and in no particular order. There are also systems which do not use a central controller that sits on one frequency and continually broadcasts as these systems do. An example of one is LTR systems which, instead, use a distributed system relying mostly on the user radio's internal computer and separate controllers on each of the repeaters used by the system. These are not nearly as common for public service (police, fire, etc.) usage as the EDACS and "Motorola" based systems, however, and I will not go into those further here. Also, trunking systems can carry either standard analog FM type radio traffic or can carry newer digital modulation modes or a combination of both just as conventional systems can.

If you were to monitor such a system on a conventional scanner without trunking capability (assuming the voice modulation mode was compatible) or with a trunking scanner in conventional mode (scanners with trunking capability are still able to function in conventional single-frequency-per-channel mode if desired; there are still many conventional systems around which you may be interested in in addition to the trunking systems) then what you would hear is a "mishmash" of traffic on each frequency in the system. If you park on any voice frequency in the system you might hear one part of a communication between a police patrol officer and dispatch followed by a part of a conversation between two municipal waste management officials and then followed by an EMT communicating with a local hospital. On a small system with few users you might be able to follow the correct conversation by simply putting in all of the voice frequencies and pressing SCAN when the conversation switches radio frequencies to attempt to follow the conversation. However, on very busy and/or large systems with many users you would become overwhelmed quite easily and attempts to follow conversations of interest become untenable using this method. This is why you need a "trunking scanner" programmed with the correct trunking control frequencies and system type(s) and set to monitor this mode.

Scanners that can track trunking systems are able to "hear" and "understand" the central controller's digital language. They first must be programmed to have at least the control channels (frequencies) for the system to be monitored entered into them if a Motorola variant and all of the system frequencies in the correct LCN order for EDACS systems. Then they must be told which type of system it is that they need to track so that they are set to the correct system "language", for example, Motorola or EDACS. With this minimum information, if correctly entered, the scanner can track the trunking system and hear all of the non-encrypted traffic communicated across that system and follow the conversations. Scanners typically have a setting that allows you to hear everything transmitted on the system (not encrypted, of course) in case you don't know the specific talk groups you want to listen to on that system or in case you simply want to "search" for new talk groups. However, they also have the ability to be programmed to follow specific talk groups such as those groups for the police and fire departments for the city and/or county that you are interested in. So, to answer your question about being able to listen to specific users, yes, you can. You just need to understand that, now, with trunking systems, you are now looking at specific codes known as talk groups rather than specific frequencies. You do need the system's frequencies for use by its central controller and get those into the scanner but the frequencies themselves no longer differentiate specific users.

This is a very basic explanation just to get you familiar with the basic concepts. You should know that there are many different types of systems in use and not all of them are capable of being monitored and tracked by the current crop of consumer scanners. Your next step is to go to your state's forums in the RR site and ask questions about the area and system you are interested in. You should ask what scanner models others in your area are using that seem to work well for what you are interested in monitoring and how best to set them up and program them. They should be able to help you in programming the scanner for that area and may even be able to give you programming files that you can upload to your scanner with the appropriate software from a computer.

-Mike

 

[EP204]

Mike, I think that is the best explanation of trunking I have ever heard.