TIII (MOT) Systems

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Annunaki

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Hey guys I recently found a new system pop up near my QTH that seems to be using a TIII (MOT) system that is using LCNs rather than TIII (HYT) LSNs.

Here is my data for this TIII (MOT) system which has its CC on CH 3

Code:
TIII, 1, 1, 3, 445.8250, 445.8250, 3
TIII, 1, 1, 11, 445.9250, 445.9250, 11
TIII, 1, 1, 12, 445.9375, 445.9375, 12
TIII, 1, 1, 13, 445.9500, 445.9500, 13
TIII, 1, 1, 14, 445.9625, 445.9625, 14
The issue I am having is that DSD+ is seeing the VC frequencies as LSNs and not LCNs and obviously thinking CH 11 and 12 are the same frequency and the same for CH 13 and 14 and not following 11 and 13 correctly.

Is there a way to tell DSD+ how to use LCNs rather than LSNs for TIII (MOT) systems?

TIA
 

cg

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Logical channel numbers are what the standards call them. Motorola and Hytera use the same standard but may use different terms to describe them.
Looks like you populated the .FREQUENCIES file incorrectly.
11 & 12 are the same frequency, one is the first slot and one is the second slot
Your .FREQUENCIES file might show
TIII, 1, 1, 11, 445.9250, 0.0, 1,
But means
TIII, 1, 1, 11, 445.9250, 0.0, 1
TIII, 1, 1, 12, 445.9250, 0.0, 1
The odd channels are the first slot and the even channels are the second slot.

chris
 

spikem

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They are in freq pairs. I have 11&12,35 &36,37&38 on three different frequencies. two channels to each frequency. Not too certain about your last question. 11 & 12 are on 445.9375 but you only need to enter ch 11 in the freq file
 
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Annunaki

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Logical channel numbers are what the standards call them. Motorola and Hytera use the same standard but may use different terms to describe them.
Looks like you populated the .FREQUENCIES file incorrectly.
11 & 12 are the same frequency, one is the first slot and one is the second slot
Your .FREQUENCIES file might show
TIII, 1, 1, 11, 445.9250, 0.0, 1,
But means
TIII, 1, 1, 11, 445.9250, 0.0, 1
TIII, 1, 1, 12, 445.9250, 0.0, 1
The odd channels are the first slot and the even channels are the second slot.

chris
That maybe so but the LSN/LCN calculator does not produce the correct frequencies for the channels in LSN mode but in LCN mode they do sort of line up and FMPA follows the calls fine apart from CH 11 and 13 either way I set it up.

When the CC tries to pass a call to CH 11 or 13 nothing is heard so FMPA switches back to the CC however If I intercept FMPA and manually tune to what CH 11 and 13 should be I can hear the comms just fine.

Strange system indeed.

Take for example this TIII (HYT) system which uses proper LSNs (Which works perfectly fine but acts totally different to the above system)

Code:
;  Manchester Airport Lanside Operations
TIII, 1:2, 1.1, 33, 440.2000, 440.2000, 33
TIII, 1:2, 1.1, 143, 440.8875, 440.8875, 143
TIII, 1:2, 1.1, 199, 441.2375, 441.2375, 199
TIII, 1:2, 1.1, 307, 441.9125, 441.9125, 307
Regards
 

slicerwizard

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When the CC tries to pass a call to CH 11 or 13 nothing is heard so FMPA switches back to the CC however If I intercept FMPA and manually tune to what CH 11 and 13 should be I can hear the comms just fine.

Strange system indeed.
It's not strange at all. You've messed up the channel entries for LSNs 11, 12, 13, 14. You have four different RF frequencies for two DMR RF channels. Of course it doesn't work. Why do you have entries for LSNs 12 and 14 in the .frequencies file??
 

cg

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There are several ways that a system can calculate the logical channel numbers. One is by math, step times the channel # added to the base frequency. You then get a system that looks like your Manchester example. Another way is for the system manager to simply assign numbers to the frequencies. I suspect you tried to run the channel numbers through a calculator when it is simply somebody saying 445.8250 is channel 3, 4xx.xxxx is channel 11, 4xx.xxxx is channel 13, etc. You need to find the other frequencies and determine which one is active when DSDPlus says channel 11 or 13 has voice. You then edit the .FREQUENCIES file and put the correct frequency in the correct channel line.

chris
 

Annunaki

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There are several ways that a system can calculate the logical channel numbers. One is by math, step times the channel # added to the base frequency. You then get a system that looks like your Manchester example. Another way is for the system manager to simply assign numbers to the frequencies. I suspect you tried to run the channel numbers through a calculator when it is simply somebody saying 445.8250 is channel 3, 4xx.xxxx is channel 11, 4xx.xxxx is channel 13, etc. You need to find the other frequencies and determine which one is active when DSDPlus says channel 11 or 13 has voice. You then edit the .FREQUENCIES file and put the correct frequency in the correct channel line.

chris
Thank you this is the constructive response I was looking for.

Yes I ran it all through the calculator that is in this forum (just like I did with the Manchester example which worked out fine) but this system did not which tripped me, Now you have explained what is possibly happening here I now understand what I need to do.

Cheers (y)
 
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