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DSD+ Tracking Multiple Systems?

Joined
Dec 23, 2008
Messages
5
#1
I'm using DSD+ to trunk track an apco P25 system using a single RTL SDR dongle. I'd like to track a second system. Does DSD+ support tracking multiple trunked systems?

Thanks,
Dan
 

DaveNF2G

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#3
You don't really want to do that. The program will save one set (each) of talkgroups, radio IDs and frequencies. Assuming that the SysID is also preserved as part of each entry, eventually you will have files that are unmanageable. I don't know what the ultimate size limit is, but eventually it could become too much info to process or search through during the length of a single transmission, so you would not be able to keep up with the channel grants.

For multiple systems, you need multiple instances, each in a directory of its own with its own system-specific data.
 
Joined
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#4
You could create a scanlist with the control frequencies in it - I assume you have FMP24 connected to DSD+ via tcp.

It will scan the trunks and stop on them when voice is detected then move on with the scan when voice is not detected - I use this to monitor several lower traffic trunks and it works well for me... I have a X seconds delay for each in the scan list in case there is a reply.
 

GTR8000

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#5
You don't really want to do that. The program will save one set (each) of talkgroups, radio IDs and frequencies. Assuming that the SysID is also preserved as part of each entry, eventually you will have files that are unmanageable. I don't know what the ultimate size limit is, but eventually it could become too much info to process or search through during the length of a single transmission, so you would not be able to keep up with the channel grants.

For multiple systems, you need multiple instances, each in a directory of its own with its own system-specific data.
There is no "need" for multiple instances in their own directories. It may be good practice to keep them separate, but a necessity it most certainly is not. Some DSD+ users have a single set of files in a single directory for multiple systems of all types. Some of those files have thousands upon thousands of entries and have grown quite large. Again, that may not be ideal practice, but it remains fully functional. It takes the software mere fractions of a second to look up data in those files.
 

GTR8000

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#6
You could create a scanlist with the control frequencies in it - I assume you have FMP24 connected to DSD+ via tcp.

It will scan the trunks and stop on them when voice is detected then move on with the scan when voice is not detected - I use this to monitor several lower traffic trunks and it works well for me... I have a X seconds delay for each in the scan list in case there is a reply.
I'm not sure that how you've described it makes sense. If you put control channels into a scan list, FMP24/DSD+ is simply going to stop scanning when it acquires the first control channel. Since the carrier never drops, and there is no audio to process, why would it move on to the next scan list entry?

Perhaps you meant to say "you could create a scanlist with the voice frequencies in it" :unsure:
 
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#7
I'm not sure that how you've described it makes sense. If you put control channels into a scan list, FMP24/DSD+ is simply going to stop scanning when it acquires the first control channel. Since the carrier never drops, and there is no audio to process, why would it move on to the next scan list entry?

Perhaps you meant to say "you could create a scanlist with the voice frequencies in it" :unsure:
No - Control frequencies are in the scanlist.

Regardless of the continuous carrier it only stops if there is voice on the trunk.
 
Joined
Dec 23, 2008
Messages
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#8
No - Control frequencies are in the scanlist.

Regardless of the continuous carrier it only stops if there is voice on the trunk.
Thanks, I think I'll give it a try. I'm new to fmp24/dsd+.. Do you have an example scanlist file you can send me?

Thanks,
Dan
 
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#9
Thanks, I think I'll give it a try. I'm new to fmp24/dsd+.. Do you have an example scanlist file you can send me?

Thanks,
Dan
Sample FMP24 scanlist for P25 trunks (although you can have mixed types in the same scanlist

771.41875 P25 BW=9.5 DELAY=5 Region East
773.86750 P25 BW=9.5 DELAY=5 Region West

If you have only one tuner you will need to use -r1 in the DSDPlus bat.
 
Joined
Dec 23, 2008
Messages
5
#10
No - Control frequencies are in the scanlist.

Regardless of the continuous carrier it only stops if there is voice on the trunk.
I tried it and it works ok. It would be nice if there was a way to make it dwell on each control frequency a bit longer.. Every time it switches it rebuilds the frequency list so there is some wasted time on each switch.

Thanks,
Dan
 
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#11
Well I am glad it works for you.

I agree about a WAIT feature which could be incorporated in the scanlist like the DELAY feature, I actualy requested the dev team to take a look at including it but so far it never made the cut. Perhaps if more requested it, it may get included, it seemed to me it would not be a huge feature option to include, but maybe it is.
 
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#13
Is there a place I can go to formally request this feature? Or do the devs watch this group?
I think the official way is to send an email to the fastlane email address.

What I requested was a scanlist feature that would accept a WAIT instruction like this...

771.41875 P25 BW=9.5 WAIT= 5 DELAY=5 Region East

5 representing the desired wait time before moving on with the scan. Delay would remain the same.

When scanning a list of control channels this provides an opportunity to catch voice activity - right now it moves on so quickly I am sure much is missed.

Anyway thank you for the request support, I think it to be very useful feature for some scanning applications.

Hopefully the great dev team does review threads here at RR as well.

For the record I just sent the request to the FL email address as well.
 
Last edited:
Joined
Jun 12, 2013
Messages
111
#16
In my application, there is say 3 CC's that rotate every 24 hours or so. The CC's are all on slot 1.

I think the reasoning is to spread the load over 3 BS's to even out wear.
 
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#18
It would also be nice if the scan list would skip over voice and only lock onto CC...
I have no idea if any of these DSD+ switches would give you what you want, I have to say I have not used any except -m1 which for me is a money card when I do mixed analog/digital scan lists

DSD+: Added raw source audio monitoring modes

The -m<num> command line option and the M/m active keys select one of the five
available monitoring modes:

0: never monitor

disables raw source audio monitoring

1: monitor if no sync and a signal is present (**)

enables monitoring if DSD+ is not detecting known sync patterns
AND noise content is low enough to indicate the presence of a signal

2: monitor if no sync

enables monitoring if DSD+ is not detecting known sync patterns

3: monitor if no voice

enables monitoring if DSD+ is not processing voice frames

4: always monitor

enables full time raw source audio monitoring
 
Joined
Jun 12, 2013
Messages
111
#19
"I don't get it. A scan will land on the next CC fairly quickly anyway, no? "

Yes but not as fast as if it would when ignoring voice (not a biggie). The scan could be of two types. 'Normal' and 'Stop On CC Only'...

But it does however (annoyingly) populate the groups file with non groups. ie, DMR. See attachment (the red 'X').

Call me OCD or whatever (I've been called a lot worse), but hey! It would be a nice function.

Thanks.
 

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