How to search LCN's

[gcopter1]

I have the SDS200 and would like to know how to go about, mapping LCN's on an LTR system.

In RR, there's a few systems in my area that, by their account, have missing LCN's.

I went ahead and downloaded one of these systems. Next, I used the Analyze feature. When the scanner started the search, it only listed the two known LCN's although RR lists more. Granted, the additional LCN's are unknown but, just how can I use the features in the scanner to help me fill in those unknowns?

How can I tell the scanner to look for those frequencies when the Analyze LCN's, only searches between the known 2?

 

[IAmSixNine]

Thats due to how LTR works.
Radios are programmed with a home channel, They use it first to look for a channel grant. If the channel is clear its granted, if not the controller will tell it what channel to go to. In your case it sounds like a system that is not too busy. So the primary and second channel are the main ones used. If its not a very busy system it may not map out the other channels for a while.
Back when i worked for a 2-way shop, we would often put large customers on their own home channel to prevent them from getting to many busys or waiting to long for an open channel.

 

[gcopter1]

Makes sense. Thanks for the explanation.

 

[pb_lonny]

Maybe run it a bit longer and see how it goes?

 

[sonm10]

or the frequencies are not even in use. I just did the same for my area and found this to be true.
Try scanning the frequencies conventionally. If they are in use, you should hear little data blurbs, almost like bits of static or a keyup.

 

[gtaman]

I know older radio shack scanners had a good LTR finder. The pro 163/164 was how I mapped mine.

 

[gcopter1]

or the frequencies are not even in use. I just did the same for my area and found this to be true.
Try scanning the frequencies conventionally. If they are in use, you should hear little data blurbs, almost like bits of static or a keyup.

That's not quite the situation I have.
I accept the published frequencies on the RR database. However, they also publish 7 more empty spaces, for LCN frequencies.

I'm just trying to use my scanner, since I live in the county where the system is, to contribute the missing info, if any, to the database.

Seems to me the explanation given by IAmSixNine, the most plausible one.

Just programmed the system in my scanner today, will be monitoring it and see if I can develop any more frequencies.

Then it would be a matter of mapping the order out using the LCN feature.

 

[hiegtx]

That's not quite the situation I have.
I accept the published frequencies on the RR database. However, they also publish 7 more empty spaces, for LCN frequencies.

I'm just trying to use my scanner, since I live in the county where the system is, to contribute the missing info, if any, to the database.

Seems to me the explanation given by IAmSixNine, the most plausible one.

Just programmed the system in my scanner today, will be monitoring it and see if I can develop any more frequencies.

Then it would be a matter of mapping the order out using the LCN feature.

I've had the same issue with finding the correct LCNs. While the systems I've been dealing with are DMR, you still need to identify the correct LCNs. The problem, as it may be in your case, is that there is not enough activity for the system to utilize more than a couple of the frequencies. So, while there are additional frequencies on the license, for that location, unless there is enough activity to bring the additional frequencies into play, I won't get an accurate read on all of the LCNs in use. One local system, I let run for almost a week before it finally used one of the unknown frequencies.

 

[sonm10]

That's not quite the situation I have.
I accept the published frequencies on the RR database. However, they also publish 7 more empty spaces, for LCN frequencies.

I'm just trying to use my scanner, since I live in the county where the system is, to contribute the missing info, if any, to the database.

Seems to me the explanation given by IAmSixNine, the most plausible one.

Just programmed the system in my scanner today, will be monitoring it and see if I can develop any more frequencies.

Then it would be a matter of mapping the order out using the LCN feature.

From what I've read about ltr systems is they tend spread the channels out so each repeater gets used. Those empty channels are just place holders.
If you are still in doubt, check the fcc licenses for the entity, and scan all the repeater outputs (anything with a fb) and listen for data bursts.

 

[werinshades]

I've had the same issue with finding the correct LCNs. While the systems I've been dealing with are DMR, you still need to identify the correct LCNs. The problem, as it may be in your case, is that there is not enough activity for the system to utilize more than a couple of the frequencies. So, while there are additional frequencies on the license, for that location, unless there is enough activity to bring the additional frequencies into play, I won't get an accurate read on all of the LCNs in use. One local system, I let run for almost a week before it finally used one of the unknown frequencies.

In these situations I use Custom Search to identify the Color Codes. Once you do that, create the Favorite List, System, Site in Sentinel and Write to Scanner. After that step is completed, go into scanner menu and scroll for Analyze/LCN Finder. Press the Function knob and let it ride. I have done this with quite a few MotoTRBO Trunking Systems successfully. If these are One Frequency Trunk Systems (Denoted by DMR during Custom Search), LCN's aren't needed.

 

[cg]

In the older scanners (996 series, perhaps older), LTR Channels and IDs would pop up if you searched a range with Control Channel Only turned on. I don't know if you can force the "New and Improved" scanners to do that.

 

[IAmSixNine]

Its common for LTR systems to have 1-20 LCN but lets say 4 frequencies are licensed. They may use LCN 1 LCN 5, LCN 10, LCN 15.
I worked for a 2-way shop in the early 2000s and we had several LTR systems. All had status bit 0, Home channels varied based on customer load and each system had channel spacing on LCN, We had one with about 8 channels and 4 were used as Home channels. The LCNS were all the same, LCN 1, 3, 7 10, 12, 14, 18, 20. We used 1, 7 10 and i think 14 or 18 as home channels.
1 customer was a concrete truck company and they used data terminals, that had its own home channel. Another was a courrier service who had their own home channel.
We had 1 home channel for customers with just a few radios..
We also had some customers who were night heavy users aka security and put them on the same home as the concrete truck data devices.
I never ever saw an LTR system set up with all slots at the beginning filled up. They were always spaced out.