Little Rock TRS Talkgroups

[ArkieRanger]

In searching for talkgroups on the Little Rock TRS, I have found that the following can be used as a guide when determining who an unknown talk group is associated with:


<1000 - Little Rock Police
6*** - Little Rock Fire Department
12*** - Little Rock (City Departments)
13*** - Little Rock (City Departments)
32*** - UALR Maintenance & Unknown others
33*** - MEMS
44*** - Pulaski County
48*** - North Little Rock
49*** - North Little Rock & Sherwood
50*** - Sherwood & Maumelle
51*** - Cammack Village
58*** - PDASP (Interagency Common)
59*** - Central Arkansas Transist
60*** - Central Arkansas Transist

I would appreciate any corrections or additions. I have found approximately 150 talk groups and most fit into this guide but I'm sure there are additional ones out there.

 

[alltwist77]

Everything you posted looks pretty good. Using Trunker for a couple of months now, I have been able to pick up 241 talkgroups. Among them are ranges of channels that are seldom seen in use. Due to that fact, I couldn't say with any certainty what their usage is. Channels not fitting into your above-mentioned ranges are:

1008, 1040, 1072
1616
2096
2448, 2512, 2544, 2576, 2608
2800
4736
4816
8080, 8128
9776
10000
11952
16016, 16048
16432
16880
17616
20656, 20688, 20720
20816, 20848
22416
22640
29136
29968
40016
40400
41072
45008, 45040
47760
62224
63648

About the only ones I have any idea on are the 45***'s, which I believe are also Pu. Co. related.

 

[ArkieRanger]

U've done a great job! That is by far more talkgroups than I expected to be on the system. The 8*** series groups, that seems to be some sort of transportation similar to CAT but not sure who it is. I had some hits on talk groups in the 60,000 series but didn't know who it was over there.

I've found the best way to figure the talk group out is to isolate a particular talkgroup and use the VOX recorder for a day or so to figure out the channel activity. Problem with that is that it takes a while with one talkgroup at a time.

Have you heard anything about a 2nd Interagency Talkgroup similar to PDASP? I heard that when Cammack Village came onto the trunk that they were wanting a 2nd Talkgroup added to the TRS for interagency communications.

 

[ArkieRanger]

Also, some of the talkgroups you posted resemble the talkgroups I have for Entergy -- this might be explained by some sort of calculations that Motorola uses when assembling a TRS

 

[alltwist77]

I'm not sure that I have ever personally caught any traffic on either of the 8***'s. Looking through my Trunker files, I have 8080 with only 2 hits and 8128 with 8 hits. It would most likely be a long wait to even record any transmissions on them. Then again, 8128 was active yesterday morning.

Concerning the 60,000's, I think all of the 60*** are CAT (like you mentioned in your earlier post). Just from memory, it seems that most of the times that I have caught them were involved with the repair shop. Not sure about 62224 (which has only one hit) or 63648 (which has only three hits).

A lot of the talkgroups I posted earlier have never been observed with traffic. Trunker will pick a number of them up when a radio affiliates to the talkgroup. So basically, they might not even get used much anyway. However, someone has them programmed into their radio so you never know when or why it might become active.

On the issue of interagency talkgroups, I have some questions also. Looking through affiliation logs, a lot of the 20***'s seem to have a wide range of users: NLRPD, MEMS, Maumelle, Cammack Village, and PCSO. I can't decide what these talkgroups are being used for.

While I'm thinking about it, I missed a few talkgroups in my earlier post...

34320
52496
57856

 

[alltwist77]

I've noticed that CAT must have gotten a lot of new Type II radios and moved much of their traffic to 32880. There's still a lot of confusion as people call on 32880 and the dispatcher responds on 700-5 until they figure out it's on the other radio. I would imagine that they intend to phase out the older channels at some point.

 

[Thunderbolt]

This will be really interesting if they can obtain the funding to switchover to digital. I know that ASP's long term plan is to upgrade their system to digital but in order to do that they would need to add a lot more towers to those currently in place. Likewise, they would need to add a very good microwave backbone to insure complete statewide coverage.


73's

Ron

 

[ArkieRanger]

I know in addition to the regular TRS system, there are also 4 TAC channels that are used between departments and also for general conversation. I have identified a couple and wonder if anyone has identified the others - thanks.

TAC 1 866.51250
TAC 2 867.01250
TAC 3 ?
TAC 4 ?
DIRECT ?

It is also worth mentioning that the TAC channels listed in the Radio Shack frequency book (for nationwide TAC assignments) don't match what is in use here. I have identified and matched the two TAC channels above and are correct.

It seems like whenever there is some type of joint rescue operation on the Arkansas River, the local agenies use TAC 2 -- this has made for some interesting monitoring.

 

[alltwist77]

They are using, and have even licensed, the national Interoperability channels. I haven't kept track of what they call each channel. TAC 2 (also called TAC 2R) is pretty commonly used. I hear it being used not just for river rescues, but mutual aid between NLR-Maumelle and Sylvan Hills/Sherwood-Jacksonville fire departments. I'm pretty sure this matches the nation plan.

LRPD uses one of the other frequencies for direct traffic. Most of the time you have to be close to receive it. Occasionally, you can pick them up across town. I'm not sure of the reason for that.

I'll pay a little more attention to these channels and see if I can provide better details. As it stands right now, I don't think most of the channels are used except in extremely rare instances. There's just the two above that I am aware of.

While we are on the subject of alternate local department frequencies, NLR has a backup emergency channel on 855.2375. The fire department does a daily dispatch test on this channel every evening, and it would appear to be setup for this purpose should something happen to the LR TRS. In the meantime, NLRPD uses it for direct talk. You've gotta be within about a mile or so to pick it up.

 

[ArkieRanger]

Ok - after putting the nose to the grindstone this weekend to figure out these TAC channels, here is what I was able to determine:

TAC 1 - 866.5125
TAC 2 - 867.0125
TAC 3 - 867.5125
TAC 4 - 868.0125
NATIONAL CALL - 866.0125

It seems like most of the action I was able to monitor was "rag-chewing" between patrol units. If fact, there was an interesting exchange on the National Call frequency where two Little Rock units were complaining about the length of time a call held before it was dispatched to them. Sometime later, two Little Rock units were complaining about the department's new AVL Tracker. Not sure if they monitor this channel in their dispatch center but it has had some lively conversation.

Thanks for the info about NLR's backup system. I'll plug that into the scanner. I had always heard that there was supposed to be some sort of inter-agency plan to use the TAC channels in the event of a TRS failure but had heard from someone in NLR that they had there own backup system - this must be it.

 

[Elwood]

The four TAC channels are actually eight channels. The difference is whether there is an R attached to the channel number. TAC2 and TAC2R are the same channels, but the R indicates that the repeater function is being used. If TAC2, but not TAC2R, then it's a direct, simplex, frequency for car-to-car usage. The TAC freqs are not part of the Little Rock trunked system, but are on the same towers and programmed into the same radios. They are used mostly when the main trunk system goes down, or when there are interagency events that they don't want to tie up the trunked system for.

The National Calling frequency is used mostly by Little Rock Police Dept to just chat on. You can hear some really interesting stuff there sometimes. I don't know if they realize that their dispatchers do monitor that channel or not. I'm pretty sure they aren't aware of the fact that the channel is being recorded by PCSO.

 

[Elwood]

I'm fairly new to the board, but I have a lot of info about Pulaski County that I'm willing to share. And I'm curious to see if anyone has any updated talkgroup info for the Pulaski County area beyond what's been posted here so far.

While I don't have the talk group identifiers for all of them at hand at the moment, I do know that PCSO has the following channel capabilities.

Prime 1
Prime 2
Comm 1
Comm 2
Ops 1
Ops 2
PD-ASP
PD-ASP2
SH-ASP (Hardly ever used.)
Investigations (There are 2 channels for this, I think)
Narcotics

PD-ASP is used more often for interagency police communications. If a non-police agency is required, then they will use Comm 1 or 2. For example, when landing MedFlight at an accident scene, Comm 1 or 2 is used, but for pursuits, PD-ASP is used.

I've seen references to a Comm 3 running around on the net, but it is not called Comm 3 by the department, so it's named something different internally.

There are also channels for the Detention Facility and the Work Center, but I don't usually monitor them.

Additionally, they have access to TAC1-4, both simplex and repeaters, and the National Calling frequency that Little Rock uses like a CB Radio.

When listening to PCSO on the trunked system, you'll hear the following radio call groups...

100's Admin
300's Investigators
400's North Side Patrol (north of the river)
500's South Side Patrol (south of the river)
600's Judicial/Warrants
700's School Resource Officers
750-754 Water Patrol
900's Reserve Deputies

I've never heard 200's or 800's used, and don't believe they are assigned.

PCSO also dispatches for all the volunteer fire departments in the county, using three repeaters (North, South, and Central) that are tone controlled to light up whichever tower they need. These freqs are in the 150 mHz range tho. Quite often you can hear PCSO talking to Mems on Fire Central and to AET on Fire North. Occasionally there is some chat between PCSO and Lonoke County on the central repeater, but only for purposes of shared fire dispatch. Never any police calls there. PCSO also dispatches a county HazMat team on these towers, and talks with the county Office of Emergency Management on them too. (Their radio calls are EM-##) The county weather sirens are controled through data bursts on these towers also. Listen at noon on Wednesdays for the data tones for the weekly tests.

That's it for now. Once I locate the exact talkgroup numbers I have I'll post them.