Jefferson City TN LTR Standard

[jfhtm350]

I have 3 frequencies that are supposedly trunked according to fcc website (WQD204) to the jefferson city fire dept.
they are:
460.31250
460.33750
460.36250
I have been monitoring them with my Radio Shack Pro-164.
Im trying to figure out the information to trunk this.
So far i have found the following codes associated with the frequencies:
460.31250 165DC
460.33750 LTR 0-01-100 R01
460.36250 (havent found code yet)

Does this make any sense to anyone that one is not showing an LTR code but a DC code?
There is only one group on these frequencies that i can find.
Why would there only be one group on an LTR trunked frequency to begin with?

Maybe someone will help me figure out whats going on here.

 

[captclint]

Welcome to RR. Yes. Often, a group of LTR repeaters will have one or more conventional frequencies. That is why you are getting 165DCS. While not normal, small systems may start out with one or two LCN's. In this case, you may not find the 2nd if it is a go-to repeater until there is a fire. I can't much advantage in having only 1 LCN, except that you can select the Groups you want to receive similar traffic, but 2 users/TGID's couldn't be on at the same time. You'll find some other tips in Mapping an LTR System - The RadioReference Wiki

On another note, these look like "relatively" low power fireground frequencies. Repeaters are usually considered "unreliable" for fireground because they don't penetrate buildings and basements well. 20W makes that even worse unless the town is small and the repeaters are very near town. I'm also surprised they would go with LTR, which adds another level of reliability if the computer that controls the switching is acting up, getting noise, etc. but this is less of an issue than the 20W repeaters.

 

[jfhtm350]

Yes sir i have read that page and im trying to understand how all this works. This is my first time fooling with trunking period. Knox county (the next county over) is motorola trunked so i may fool with that a little later on but right now im trying to makes heads and tails of this deal because i want to monitor Jeff City Fire and really dont care about knox county.

I have heard the fire dept talking on 460.31250 without anyone talking on 460.33750 and vice versa for those two frequencies. As for 460.36250, so far i havent heard anything on that channel and like you say it is probably is an overflow channel. The other conventional frequencies registered, 154.13000 and 154.28000, i have not heard a peep out of those either.

Im having data bursts from channel 460.33750 so i am assuming that is the home repeater and no data bursts from the other two.

Now i have to have the other two frequencies LTR information to program it correctly in my scanner, right?
or at least one more?

All i know to do is just wait and hope to catch the overflow channel (460.36250) broadcasting in hopes i can catch the LTR code on my scanner, right?

Jefferson City is a fairly small town, and i really dont see a reason for the fire dept to have a trunked system unless the city is planning on cutting back on the frequencies they register and combining the police fire and ems etc into groups on a trunked system.
That is the only reason i can understand to have a trunked system in the first place that is to have more than one group on it (fire, police or other). Instead of having just the fire dept on it.

Your 2cents worth is greatly appreciated.

 

[captclint]

Now i have to have the other two frequencies LTR information to program it correctly in my scanner, right? or at least one more?

The one that is conventional will not be part of the trunk system, so you can leave that as a standalone. Yes, you would need to get the LCN number for 460.36250 to have it trunk properly, but with only 2 frequencies, you can probably catch 95% of all conversations by programing all three as conventional.Stiil, it is a "fun" type challenge to get the trunking part mapped.

 

[jfhtm350]

Yes CaptClint, i see it can be a challenge to map these things out. Ill be laying in the bed and hear a strange broadcast on the scanner and jump out of bed to try to catch the code on the screen only to get there a split second too late to see it. Ha. Yes i have them programmed in a conventional way now and more than likely gonna leave it that way.

I have been checking out Knox Co's motorola type II trunking system to see if i can figure that type of deal out and i see there is about a hundred groups on their system. At least someone has found all or most of the groups on that system. Now im reading things about programming in a base, offset and step frequency and dont understand that. I feel like i need an FCC license to operate my scanner and im not your average dummy when it comes to things like this.

Do you have any words of advice on motorola type II trunking?

 

[captclint]

Do you have any words of advice on motorola type II trunking?

Sorry, no experience. Try discussing your interest in the TN forum. This one is not about specific systems.

 

[jfhtm350]

Well CaptClint, the channel that i did not have a code for has been real active today (460.36250). It comes in as a fairly weak signal. Im guessing it is digital because it sounds kind of like morse code coming through. Ha. Let me tell you the real kicker.
Its coming up as a motorola trunked channel on my scanner. There was a couple of groups showed up and then it said control channel.
Could this be a mistake because of a little noise and the scanner picked it up wrong or something?
So this is what i got so far.
460.31250 165DC
460.33750 LTR 0-01-100 R01 (data bursts)
460.36250 Motorola Trunked Control Channel.

 

[captclint]

The fact that one of these is coming in weak(all 3 should be about the same signal strength) as Moto would lead me to believe you are hearing another system. Is this Cumberland County Public Safety Trunking System, Crossville, Tennessee within 30-35 miles of you? If so, that is probably what you are hearing, and it is digital.

On an other note, I assumed you were working on a system that was not in the DB. Guess what, here it is and they claim it has all LCN's identified. Jefferson City Trunking System Now the history is very recent...created on 10-25. Did you submit any data on this? If not, get on the TN forum and ask the Admin (KD4YGG) what he, or anyone else, knows about this system. It looks like someone just entered the LCN's using the lowest to highest freq, which suggests that they really have NOT identified them, esp since you show 460.33750 as 01, and they have it as 02.

Get on Tennessee Forum and hash this out there!!

 

[jfhtm350]

Yes, I would say your right. That location is up on the plateau a few counties over but with the snow on the ground it may be reaching out a little further im guessing. It says it is digital and a control channel for that system.

I cant search for a frequency on RR but i can on the FCC site because im a free member.
Yes i saw that RR was showing it was LTR Trunked on here but there is no groups or repeater numbers information and i did not submit any data on it.

Just now seen where you could look and see who put it on there.
How can i ask the admin KD4YGG what he knows about it or who gave him the information?

 

[captclint]

How can i ask the admin KD4YGG what he knows about it or who gave him the information?

He is an IN DB Admin (Profile: KD4YGG) so he monitors the TN forum, and may respond. I think your best bet is to just post a Subj: Jefferson City Trunking System, and ask if anyone has any more information about it. Mention that 460.31250 appears to be conventional, and 460.33750 appears to be LCN 01, which does not agree with the DB. That should attract some attention.

 

[jfhtm350]

Ok i think ill do that. Well i thank you for all of your help. Id like to help you back but id say you forgot more than what i know here. hehe.

 

[KD4YGG]

Updated based on the above information. Keep up the great work!!!