The state of Tennessee Advanced Communications Network (TACN)

[FFPM571]

There are multiple sites being upgraded in the state, as they are being serviced there are going to be times they are offline for the work being done

 

[bg_nashville]

The 'gorge' area is one of the dead zones I am trying to find more information about. Apparently there are others as well.

The problem with streaming or scanning is that you can't 'pull' a talkgroup to your tower. You have to wait until an affiliated user comes into range or forces their radio onto that site.

And, if they are having trouble (THP is one user group that is), they may be falling back to FirstNet or LTE failover or plain old just using their phones instead of even trying to do voice traffic.

This is troubling because the old coverage maps of hip-to-GTR8000 site I have says on the interstate almost 97% coverage.

Dunno, and I don't know what I don't know.

Holston Mountain is nowhere close to the gorge.

 

[bg_nashville]

There are multiple sites being upgraded in the state, as they are being serviced there are going to be times they are offline for the work being done

As I stated earlier, the site is active during the long gaps in D5 TG activity. Yesterday’s gap was from around 3 pm to about 5 am this morning.

The addition of the Elizabethton site nearby could be a factor here, but I was assuming that site is primarily for Carter County joining TACN and not a new site for state agencies.

 

[jblackst]

Honestly, I'd say that it's most likely there just weren't any THP D5 Dispatch 1 users affiliated to Holston Mtn (State) during that timeframe. The site won't broadcast any traffic from a specific talk group if there aren't any users affiliated to receive it.

 

[bg_nashville]

Honestly, I'd say that it's most likely there just weren't any THP D5 Dispatch 1 users affiliated to Holston Mtn (State) during that timeframe. The site won't broadcast any traffic from a specific talk group if there aren't any users affiliated to receive it.

I feel like we are going in circles here. That would be an extremely abnormal situation. That is the primary site for coverage of I-81 and I-26 in the Tri-cities area. There are always troopers in that area. So the question remains— what has happened in the area that would result in 12 to 14 hour gaps in TG activity on that site. I simply do not believe the no affiliation conjecture.

 

[surfacemount]

There are multiple sites being upgraded in the state, as they are being serviced there are going to be times they are offline for the work being done

wouldn't they preposition a COW for those? I can't see them downing a site for any real length of time without coverage.

Holston Mountain is nowhere close to the gorge.

THAT'S WHAT I THOUGHT. I assumed there was something else up there they were calling that. Stuff I am concerning myself with isn't in the chattanooga area. Loudon to bristol.

 

[jblackst]

I suspect that THP units on I-81 are affiliating to 02-50 (Sullivan Simul) instead of 02-44 (Holston Mtn State) since the multiple 2-50 sites are closer to I-81.

I don't get up that way much, but last December I was running Unitrunker on a laptop while driving up I-81. I was able to pickup site 02-50 from 1123a to 1216p (53 min), observing 31 hits from THP units. At the same time, I was only able to pickup site 02-44 from 1202p to 1227p (25 min), observing 0 hits from THP units. During the overlapped time, I observed 0 hits on either site from THP. Same computer, same SDR, same antenna in a moving vehicle.

It's a much shorter frame of reference, and I can not explain why you aren't hearing THP for hours on end on 02-44, but I'm offering it as a plausible reason.

 

[bg_nashville]

I suspect that THP units on I-81 are affiliating to 02-50 (Sullivan Simul) instead of 02-44 (Holston Mtn State) since the multiple 2-50 sites are closer to I-81.

I don't get up that way much, but last December I was running Unitrunker on a laptop while driving up I-81. I was able to pickup site 02-50 from 1123a to 1216p (53 min), observing 31 hits from THP units. At the same time, I was only able to pickup site 02-44 from 1202p to 1227p (25 min), observing 0 hits from THP units. During the overlapped time, I observed 0 hits on either site from THP. Same computer, same SDR, same antenna in a moving vehicle.

It's a much shorter frame of reference, and I can not explain why you aren't hearing THP for hours on end on 02-44, but I'm offering it as a plausible reason.

The only scenario I can imagine where it’s a lack of radio affiliation is that they have made changes to where the troopers are being deployed. For example, they will send a trooper to Carter and Johnson counties if they are requested by local LE, but they are no longer routinely patrolling those counties. I have noticed recently local LE being told there are no troopers available to work a traffic accident.

 

[jblackst]

Honestly I don't think there are as many troopers on the road every day as people suspect. At one point (not recently), it was common that only one trooper was on duty covering Knox and Union Counties combined (Union was still D1 then), but that's been 15 years or more ago. THP won't give ETAs to other public safety agencies, but I've waited 60 min or more for a trooper to respond to a scene. Those guys can haul, so a 60 minute drive could be a 45 mile response.

 

[surfacemount]

I can tell you exactly how many are on patrol per shift / day in the Knox district. To say they are spread thin is an understatement. Only exception to that is when they move up the interstate in a group to do directed enforcement or ballgame weekends. (overtime is good, though)

Also, they are trying to decide what talkgroups they want to use for certain activities, and they are aware of this website, discussing it by name.

 

[zachgallop]

Attached are some coverage maps for Carter County’s TACN migration that I obtained through a Public Records Request in 2024. They came from Motorola’s Radio System Upgrade & TACN Migration document. I probably should have shared these years ago, but I completely forgot.

 

[surfacemount]

Anything else you'd care to share from that document would be greatly appreciated.

 

[ka4bni]

As I stated earlier, the site is active during the long gaps in D5 TG activity. Yesterday’s gap was from around 3 pm to about 5 am this morning.

The addition of the Elizabethton site nearby could be a factor here, but I was assuming that site is primarily for Carter County joining TACN and not a new site for state agencies.

State Agencies such as THP, TEMA, and TWRA and others have access to all sites on the system.

 

[radiogod_2103]

was looking at the tacn website and seen this"TACN has exhausted the supply of surplus radios for redistribution. Because TACN does not anticipate any additional radios being turned in, we will no longer maintain a waiting list for surplus radios."

 

[jblackst]

That's for the program TACN was doing where surplus THP/TNDOS radios were being reissued at no cost to local agencies to facilitate interoperability. That program was several years ago, IIRC.

 

[surfacemount]

They upgraded, and those I think didn't have P2 in them, but they at least got a few more counties onto the system.

It would be very interesting to know what statewide system loading looks like today, and how many bonks per hour they are recording.

 

[jblackst]

This video, around 2:40, shows a screen that appears to be various sites and their 'current' channel usage.

Of course, that's a 2 second snapshot into a huge data set. I trust that the system engineers are keeping the system well ahead of 'bonks'. They're still in the process of adding more than 200 sites across the state. (TACN 2 and TACN 3 upgrades: https://www.tn.gov/safety/tacn/tacn-timeline.html )

 

[buddrousa]

All of the TACN Radios that went to help new users were APX7000 series Portables and Mobiles.

 

[surfacemount]

This video, around 2:40, shows a screen that appears to be various sites and their 'current' channel usage.

Of course, that's a 2 second snapshot into a huge data set. I trust that the system engineers are keeping the system well ahead of 'bonks'. They're still in the process of adding more than 200 sites across the state. (TACN 2 and TACN 3 upgrades: https://www.tn.gov/safety/tacn/tacn-timeline.html )

Interesting that the presentation was so TDOT HELP heavy. Wonder if they couldn't get more buy in from other users? (nice find, by the way).

 

[jblackst]

Anyone monitoring around E TN today? Weird sites showing up as peers/neighbors: 03-25 769.36875 and 03-26 769.59375. (Knox Sharps Ridge, Cross Mtn and Windrock)

Also have a 01-91 851.00625 peer on Knox Simulcast and Windrock. This is a TDOC SOW?