Unlicensed LTR System?

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wb0wao

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I have ran into a frequency that is either an unlicensed channel to an existing LTR system or a totally seperate unlicensed LTR system. Some back story is required... The local transit company - Cape County Transit Authority - is on the Dittronics UHF LTR system here in Cape Girardeau. They use two seperate TG's 0-03-001 (Vehicles) and 0-03-002 (Dispatch). CCTA also has fixed route busses that in the past did not generate much if any traffic. I assumed that I was just not picking up on them as they were on so rarely. The other day I took one of these busses and was sitting up near the driver and was listening to his radio - there was none of the traffic that I normally hear on the two above TG's, but there was a lot of chatter on the bus radio (the routes had been broken up and there was a lot of traffic about transfers and the like). So today I took my PRO-137 on a short bus trip to see if I could find the frequency that they were transmitting on and that would give me an idea of which system (if any) they were using. I did find the frequency - 459.56875 MHz - that the busses were transmitting on.

Once I got home, I plugged in 454.56875 into my PRO-107 to see if I could hear all of the bus traffic - and I did. I also heard the tell-tale LTR channel data burst on it as well. So, I put the frequency in another scanner in all 20 channels and set it for LTR and came up with the TG 0-11-008. In checking both the RR database as well as the FCC database - the above frequencies do not have any entries for an LTR system in the state of Missouri or Illinois!

Now the radio display on the bus radio said "TRANS 2" and they are currently using the Dittronics UHF LTR system for the dispatch of the taxis and the taxis as well. I would think that they would be using the same vendor - Dittronics - for everything, but that is an assumption on my part. So, my dilemma is whether or not 454.56875 is LCN11 for the existing Dittronics UHF system or if it is a part of a seperate system. I think that given the use of Dittronics for the other half of CCTA's operataion and that the bus was on TRANS 2 - it is probably LCN11 on that system. Trouble is, I don't have any way to prove it other than speculation since the frequency is unlicensed.

I would like to submit this to the RR database, but I want to have some concrete proof other than conjecture and assumptions.

Dennis
 

kilowa22

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Those are all licensed pager frequencies. Depending how close you are to the transmitter they will overload your radio and give you false reading. You will need a frequency counter to properly measure the frequency being used
 

wb0wao

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I know they are assigned to pagers, but it is being used as a LTR channel without a doubt....

1) On multiple scanners I have heard both the voice traffic as well as the data burst on 454.56875 in non-trunked mode. Nothing else was monitored - no pager data, nothing.
2) Placing the frequency in LCN11 brings up the 0-11-008 TGID
3) I was sitting pretty much directly under the antenna with the "short duck" on the '137 and monitored the bus driver when he was keying the mic as we drove around town. I even heard another bus when we were at the transfer point on the route and then monitored the driver on the new bus. This was all on 459.56875 which is the standard split on UHF.

I covered an area about 3 miles by 1 mile as I was riding the bus and the frequency did not vary and I was picking nothing else up. Normally I would agree with you that it might be an image - but there are too many things adding up for it to be that.

Dennis
 

ecps92

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MANY if not ALL of these former paging channels are being licensed up and [varies by region] are being converted to a variety LMR usages.

However, GOOD luck finding them on the FCC [Yes they are licensed !!!] as they are licensed to a Region or as the FCC calls them a MARKET [like TV/Radio markets], you should go back and [Google] the name [old days info] for 454.5750 and 454.5500 and see what is licensed. You will be suprised. :eek:

I know they are assigned to pagers, but it is being used as a LTR channel without a doubt....

1) On multiple scanners I have heard both the voice traffic as well as the data burst on 454.56875 in non-trunked mode. Nothing else was monitored - no pager data, nothing.
2) Placing the frequency in LCN11 brings up the 0-11-008 TGID
3) I was sitting pretty much directly under the antenna with the "short duck" on the '137 and monitored the bus driver when he was keying the mic as we drove around town. I even heard another bus when we were at the transfer point on the route and then monitored the driver on the new bus. This was all on 459.56875 which is the standard split on UHF.

I covered an area about 3 miles by 1 mile as I was riding the bus and the frequency did not vary and I was picking nothing else up. Normally I would agree with you that it might be an image - but there are too many things adding up for it to be that.

Dennis
 

nd5y

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VHF and UHF Part 22 paging channels are sometimes use for trunking or conventional repeaters.
Some of the frequency blocks are auctioned and the licensee can lease them to other users.

I did the following search on the FCC web site. (copied & pasted so it looks crappy)

State = Missouri, Illinois
County = ALEXANDER, JACKSON, PULASKI, CAPE GIRARDEAU, SCOTT
Frequency Upper Band >= 454.55
Frequency Assigned <= 454.6
Matches 1- 3 (of 3 )

These are the only licenses you get in those counties.
ULS License - Part 22 VHF/UHF Paging (excluding 931MHz) License - WPVD438 - Cellplus Networks, LLC
ULS License - Part 22 VHF/UHF Paging (excluding 931MHz) License - WPVF256 - WARNER COMMUNICATIONS CORPORATION
ULS License - Part 22 VHF/UHF Paging (excluding 931MHz) License - WPVF257 - WARNER COMMUNICATIONS CORPORATION

It is also strange that you are getting them in between the normal 25 and 12.5 kHz channels. You sure it isn't really 454.5625 or 454.575?

My guess is they are unlicensed.
 

wb0wao

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That is the same stuff that I found on the FCC website. The frequency is 454.56875 which is one of the splinter freqs I believe set up for the 6.3 kHz systems. I have been monitoring the specific frequency as well as the system this morning and there is another user on there (some type of excavating company I think) - 0-11-004 is the TGID.

I am starting to think that this is a seperate system rather than an addition to the current Dittronics UHF system. There is one frequency on the license for this system that to my knowledge is not used - I have never heard a data burst on it at all. Another issue I have with it is that the closest licensed frequency is over 10MHz away - that may not be a big deal, but it does seem odd that they would jump that much to add a frequency especially if they have that "spare".

Anyway, I think I will do some searching around 454.56875 to see if I can find any other data bursts on any frequencies as there has to be at least one or two more freqs for system.

Dennis
 

nd5y

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Some LTR systems have "overflow" channels that aren't home channels and don't have data bursts and aren't used much.
Some have licensed channels that don't appear to be used at all.
Some UHF LTR systems have channels in all of the band segments 450-455, 460-465, and 470-512 MHz like this one.
 
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monitor142

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As others have stated, the 454-455/459-460 were Part 22 licenses that were auctioned off some time ago. Licensing is fairly hard to figure out as it's different then your normal LMR licensing. The licenses covers a specific geographic area rather than a specific site. They have a "chunk" of spectrum and they can pretty much do what ever they want with it and run any split they want to maximize the block and squeeze out as many channels as possible.

We have a lot of commercial SMR operators running analog and digital in this band here in Southern California.

-M142
 

wb0wao

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Cape Girardeau, MO
Lots of good information, I may have to revisit my thoughts on the system architecture. I am working on another system (just about have the two unknown LCN's nailed down) and once I finish that one up, I will work on it and try and get it nailed down.

Dennis
 
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