Hi I have DSD up and running with fmp24 and DSD (1r.bat) communicating correctly. I can manually tune and hear decoded audio. I have made sure that combined CC/VC is checked. I don't have any channel 'hopping' occurring I can't find anything on this sites databases for my area, the guides I have read say to edit a file with the control channel information but I am starting from scratch without the opportunity to populate the file with local information. I even have seen messages like 'control channel found' in the event viewer. but no channel changes occur. In the youtube video by corrosive, there is a dos like window which has 'tuning to xxx.xxxxMhz' But I don't seem to get this. Any pointers where I'm going wrong. I have been searching for an answer to this but don't appear to be making any headway.
DSDPlus DSD+ FL single dongle use.
- Thread starter H_S_B
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Can you give us a hint as to what you are trying to decode? Is it a P25, NXDN, DMR or some other system? Without knowing the details of the system you are attempting to receive, it is hard to help you. Just wondering if you have Voice/Data Call Following selected?
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If it is P25, should work from just the control channel
Most DMR you need to correctly enter data into the .Frequencies, .Network, & .Sites files
Most NXDN, the same. You need to populate data into the same files
chris
Most DMR you need to correctly enter data into the .Frequencies, .Network, & .Sites files
Most NXDN, the same. You need to populate data into the same files
chris
Can you compare the frequencies you are monitoring to the RadioReference database information for your area?
If you are getting any decoding, the program tells you what the signal is. Event Log Window, lower left corner.
chris
chris
There is no data in radio reference for my area, which is why I'm stuck. Most of the guides out there use this as a starting point but I have scanned my nearest and there is nothing there.
What is your area? There are other places to get freqs for areas not listed in the db.
slicerwizard
Member
You have a nice strong control channel signal. DSD+ is telling you that voice calls are taking place on channels 27/28, 35/36 and 37/38. Those channels are also going to be nice and strong. You should have no trouble finding them.
So do I have to manually scan to find what frequencies the channels are broadcasting on and then enter the data into the frequencies file? When running with 2 dongles I understood that one dongle monitors the CC and tells the other dongle what frequenct to tune to. I can't see the frequency though just the channel number, is there a way to establish this without guessing? are the VC channels necessarily nearby so I can see them come on when the CC says there is VC activity?
What is the freq of the control channel? Whats on the other active freqs in your pic? Do any of those have a talk group 512 or 524?
Correct, you have to put a little effort in here to make things work. Typically you can only scan P25 trunked systems by only knowing the control channel frequency. Other formats like DMR Tier III/Connect Plus, EDACS etc require you to know and manually enter the frequency data.
OK thanks, Has any one done a guide for mapping the TII information on the CC to find the CC? Do I scan other channels looking for a corresponding channel number then edit the frequencies file to match it?
The TX and RX data fields in the frequencies file do they correspond to TX=CC and RX=VC?
The TX and RX data fields in the frequencies file do they correspond to TX=CC and RX=VC?
A guide would be something like:
Find the control channel and run it for a bit to establish some of the system information. Look at RadioReference to see if the system is there. If not...
Populate the .Network file with the system information. Tier III uses Area Length as an additional field. 5 is the default area length so I suggest using that:
TIII, 1, "big radio company", 5
You can also populate the .Sites file with what info you have so far. Your system may show different info once you have populated the Area Length into the Networks file. It should show Site info as 1.1, 1.2, etc. Your example has 4 sites (3 Neighbors) so:
TIII, 1, 1.1, "North"
TIII, 1, 1.2, "South"
TIII, 1, 1.3, "East"
TIII, 1, 1.4, "West"
To gather information for the .Frequencies file, you need to determine if the channel numbers are band plan based or picked by the company. If you see something like 345, 512, 633 these are very likely Band Plan based. If you see something like you have, 27, 35, 37 those are random and require more work. If you are in a country that shows the licensing data online, you can take the control channel information and go searching. Otherwise, you need to do some searching. You can start by putting the CC into the .Frequencies file. We don't know the channel number so use the "?" for a placeholder for now. Replace the xxx.xxxxx with your control channel. You only need to populate the odd channel numbers. Also, you don't need to enter a frequency for RX Frequency.
TIII, 1, 1.3, ?, xxx.xxxxx, 0.0, 0
You can set up the other channels while you are editing this file. Simply use a semicolon to prevent the program from using the line yet.
;TIII, 1, 1.3, 27, yyy.yyyyy. 0.0, 0
;TIII, 1, 1.3, 35, yyy.yyyyy. 0.0, 0
;TIII, 1, 1.3, 37, yyy.yyyyy. 0.0, 0
You can also add some info for your Neighbor Sites while you are here as well:
;TIII, 1, 1.1, 3, aaa.aaaaa, 0.0, 0
;TIII, 1, 1.2, 21, bbb.bbbbb, 0.0, 0
;TIII, 1, 1.4, 41, ccc.ccccc, 0.0, 0
Run the program and look for traffic on the Channel Activity window. When you see an activity spike, click on it. watch for matching information such as system type, TIII, channel numbers, talk group numbers, even color code info. If you get a confirmation on a frequency, edit the .Frequencies file and see if the program follows a conversation properly.
Be patient and make lots of notes. Don't be afraid to test guesses
Find the control channel and run it for a bit to establish some of the system information. Look at RadioReference to see if the system is there. If not...
Populate the .Network file with the system information. Tier III uses Area Length as an additional field. 5 is the default area length so I suggest using that:
TIII, 1, "big radio company", 5
You can also populate the .Sites file with what info you have so far. Your system may show different info once you have populated the Area Length into the Networks file. It should show Site info as 1.1, 1.2, etc. Your example has 4 sites (3 Neighbors) so:
TIII, 1, 1.1, "North"
TIII, 1, 1.2, "South"
TIII, 1, 1.3, "East"
TIII, 1, 1.4, "West"
To gather information for the .Frequencies file, you need to determine if the channel numbers are band plan based or picked by the company. If you see something like 345, 512, 633 these are very likely Band Plan based. If you see something like you have, 27, 35, 37 those are random and require more work. If you are in a country that shows the licensing data online, you can take the control channel information and go searching. Otherwise, you need to do some searching. You can start by putting the CC into the .Frequencies file. We don't know the channel number so use the "?" for a placeholder for now. Replace the xxx.xxxxx with your control channel. You only need to populate the odd channel numbers. Also, you don't need to enter a frequency for RX Frequency.
TIII, 1, 1.3, ?, xxx.xxxxx, 0.0, 0
You can set up the other channels while you are editing this file. Simply use a semicolon to prevent the program from using the line yet.
;TIII, 1, 1.3, 27, yyy.yyyyy. 0.0, 0
;TIII, 1, 1.3, 35, yyy.yyyyy. 0.0, 0
;TIII, 1, 1.3, 37, yyy.yyyyy. 0.0, 0
You can also add some info for your Neighbor Sites while you are here as well:
;TIII, 1, 1.1, 3, aaa.aaaaa, 0.0, 0
;TIII, 1, 1.2, 21, bbb.bbbbb, 0.0, 0
;TIII, 1, 1.4, 41, ccc.ccccc, 0.0, 0
Run the program and look for traffic on the Channel Activity window. When you see an activity spike, click on it. watch for matching information such as system type, TIII, channel numbers, talk group numbers, even color code info. If you get a confirmation on a frequency, edit the .Frequencies file and see if the program follows a conversation properly.
Be patient and make lots of notes. Don't be afraid to test guesses
Crikey, It's all pretty esoteric! Thanks for that I think I have a better understanding of it now, It's like frequency bingo! Yes the regulatory authority here has a listing and it is available in CSV form. It would be nice if I could somehow map regional data to sdr sharp from this by importing them as bookmarks, I may have a go at this to see if it would take some of the legwork out of Identifying some of the freqs. It is Lat and Long based so I could probably do some excel magic and create a pivot table for a specific area.. food for thought.
slicerwizard
Member
When the control channel indicates that a talkgroup is active on a voice channel, you go find a voice channel that's carrying that talkgroup. Now you have the frequency and its channel number (LSN).
No. The repeater's TX and RX frequencies. DSD+ only needs the TX frequency.
There is also a program on the forums here somewhere which should help you out with calculating LSNs, search for TIII LCN Calculator or something along those lines. If you can work out one, you can usually pin the rest together (per system, each system will have different programming however each site in the same system should work off the same LSN order)
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