LCN to Frequency calculator for DMR TIII

thewraith2008

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Calculations would be based on RF channels, not DSD+ LSNs. Step size would be 12.5 kHz (RF channels are 12.5 kHz apart)

Some scanners don't trunk track DMR, so they need no LCNs, just frequencies.
I'm using LCN here as a unique number for each frequency (RF channel) used.

So do the trunking scanners show the LCN even though they don't know the frequency?

I'm making the assumption of course if the base frequency method is used that a trunking scanner uses a base frequency and LCN and Frequency Separation [or step size] (these value are used 12.5 khz, 25 khz) to calculate the frequency of the LCN.
 

buddrousa

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The Uniden 996p2 536 sds200 need all frequencies PLUS the correct LCN's and they track DMR systems just fine.
My Whistler TRX1 and TRX2 need all frequencies and scan the voice channels for activity this has been stated even by WHISTLER REPS.
 

slicerwizard

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I'm making the assumption of course if the base frequency method is used that a trunking scanner uses a base frequency and LCN and Frequency Separation [or step size] (these value are used 12.5 khz, 25 khz) to calculate the frequency of the LCN.
You're describing a bandplan, similar to what Motorola 3600 bps systems and P25 systems use. NXDN systems and some DMR systems (like Cap+) use, or can use, arbitrary channel numbers. Rather than support bandplans as well as arbitrary channel number assignments, I would guess that Uniden only supports the latter. Whistler needs neither.
 

thewraith2008

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You're describing a bandplan, similar to what Motorola 3600 bps systems and P25 systems use. NXDN systems and some DMR systems (like Cap+) use, or can use, arbitrary channel numbers. Rather than support bandplans as well as arbitrary channel number assignments, I would guess that Uniden only supports the latter. Whistler needs neither.
OK thanks.

I may as well leave the calculator to show the base frequency what would be LCN/LSN 0 then.



Latest release: Download
HASH: eededc55c2010c7a0c385d5b7eefa11c
 

thewraith2008

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Update




Code:
Changelog

v1.4.0

Changed: UI
- Added toggle switch to change conversion mode from LSN to LCN
- Required fields are light yellow

Fixed: LCN > LSN and LSN > LCN conversion correction
- If calculating LCN, LCN was OK
- If calculating LSN, LSN was OK
- If calculating LCN, LSN was of by -2
- If calculating LSN, LCN was of by +1
I have now compared the LPCN element from channel grants using DMRDecode with the LSN seen by DSD+
  and now have aligned the two values.

Changed: Base frequency
- Base frequency is now from LCN 1. as per standards
   Referenced in ESTI 102-361-04 - C.1.1.2 Fixed Channel Plan:
    fbase - The lowest frequency in a particular band relating to logical CHAN = 1 (MHz)
- Base frequency is only relevant for LCN.
   There should be no need for it with LSN. (It is still shown be relates to LCN)
- LSN 1,2 matches up with LCN 0. LCN 0 is not a valid number therefore neither is LSN 1,2.

Added: Hidden feature - Don't generate output list
- Right click on the 'Calc LxN frequency' button

Various code clean-up

Update documentation

As usual, please read any documentation supplied.
Any questions, ask away.
Hope it works for you.



Download
NOTE: Use 7zip or WinRAR to extract files from the .7z file and read the readme.txt file for usage.
HASH: d5714d7024372e0f1b3d6a1369c94f12
 

bravo14

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I have been trying to figure out to use this. I don't understand the Ref LCN & Target LCN defualt is at 45. This is a system Talquin Electric Cooperative Trunking System, Quincy, Florida - Scanner Frequencies I was putting together years ago. I used dsdplus I don't have 1 or 2 sites setup up yet. Here is a screen shot I have. Not sure if rf spacing it is. I'm guessing 12.5khz. When I put in Ref Freq 451.025 lsn 5 than I go to target lsn 1925 target lsn freq 464.4375 nothing happens or do I need to put in the freqs in twice?

Screen Shot 12-18-20 at 08.16 PM.JPG
 
Last edited:

thewraith2008

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I have been trying to figure out to use this. I don't understand the Ref LCN & Target LCN defualt is at 45. This is a system Talquin Electric Cooperative Trunking System, Quincy, Florida - Scanner Frequencies I was putting together years ago. I used dsdplus I don't have 1 or 2 sites setup up yet. Here is a screen shot I have. Not sure if rf spacing it is. I'm guessing 12.5khz. When I put in Ref Freq 451.025 lsn 5 than I go to target lsn 1925 target lsn freq 464.4375 nothing happens or do I need to put in the freqs in twice?
Hi,

I've just noticed a bug in the calculator looking at this. See bottom for update (v1.5.0.2).

Your list of LSN/Frequencies (except the below listed ones) match up if you use:
  • Set LSN calculation
  • Ref. frequency = 451.025
  • Ref LSN = 5
  • RF spacing = 6.25 KHz

These LSNs don't match up when using above parameters:
  • 1639
  • 1640
  • 1925
  • 1926
Either the LSNs are not right for listed frequency if the Ref. frequency is supposed to be 451.025.
Or the LSNs are calculated using a different Ref. frequency.



Download
NOTE: Use 7zip or WinRAR to extract files from the .7z file and read the readme.txt file for usage.
HASH: b19d7e1f07ac1e1528e696dc03dadad1
 

bravo14

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Did you work out 1639,1640,1925,1926 LSNs. Where they wrong?
I went back and looked 1639/1640 1925/1926 are still not correct. The green boxes were missing lsn/lcn I added those over a hour ago.
Sites 1-3 I got them using dsdplus now I need to find those files and look maybe there was error on that end for the 2 not showing correctly. If I can't find the files when I go that way I'll redo dsdplus and see what happens or there is a bands opening up at night maybe try that.

Correct ones so far are
341/342
65/66
229/230
9/10
81/82
421/422
109/110
289/290
597/598
13/14
141/142Screen Shot 12-18-20 at 11.25 PM.JPG
 
Last edited:

bravo14

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I was trying to remember when I submitted the first time of the system. I think it was back in 2016 or 2017. I don't think I have those files from laptop I was using I believe those got wiped out when I redid the computer. I'll try those 2 when I go through the area see what happens I may look in the pix section I may done screen shots of it.
 

thewraith2008

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I'd be interested in knowing the answer when you figure it out.

Based on the listed frequencies (almost all of them 451-452), the LSN 1639/1640, 1725,1726 frequencies (461.7375, 464.4375) seem to be the odd ones out.
 

bravo14

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I couldn't find nothing from dsdplus files to screen shots. I did look at my submit section the 1639/1640 1725/1726 I put in back in 8/17. I did the steps you gave me to do just those 2 are off for some odd reason. I did this as a test
6.25khz
ref freq 451.025
ref lsn 5
target lsn 1639 came up with target lsn freq 456.13125. Than I put in 1725 came up with 456.400.
 

thewraith2008

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I would use DSD+ and see what traffic LSN still come up.

Are 1639/1640 1725/1726 still valid (Do you hear traffic on those LSN/Frequency as you have them listed?).
 

bravo14

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I would use DSD+ and see what traffic LSN still come up.

Are 1639/1640 1725/1726 still valid (Do you hear traffic on those LSN/Frequency as you have them listed?).
I'm too far to hear them I'm like 2 hours from those sites. I'll wait til I go through there when I go Tally one day or when I go further east.
 

zacaustin

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Hi Everyone!

I have been using this tool for a while now on some TIII networks in Australia. It has worked fantastically, with one exception...

I'm not sure if its the tool, my lack of understanding of the protocol or that the tool just won't completely work on the system I'm looking at.

The system shows as 'TIII (MOT)' in DSD+. I assume that means its Motorola's Capacity Max. The retailer does advertise the system as CapMax. I did read that this tool wouldn't work on CapMax earlier in the thread, but it has been working partially. I shall explain...

If I enter the Control Channel for any given site into the calculator and look for the voice channels it works correctly and I can hear voice on all voice frequencies, both slots using the calculated results from this tool. The frequencies returned match perfectly. This has worked for multiple different sites across this particular system.

However, DSD+ lists the sites peers and an associated Control Channel (I assume LSN as its DSD+). If I enter the peers CC LSN given by DSD into the calculator, still using the current sites CC LSN as the reference, I get the wrong result.

Is this because different sites in this system have different band plans? How do the subscriber radios on the system calculate the peer sites control channel? Is that where this tools limits are on CapMax systems? Is there a way to calculate this that the TIII tool doesn't yet support?

Any support, advice or direction to other resources is greatly appreciated.

Cheers
 
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