RadioReference on Facebook   RadioReference on Twitter   RadioReference Blog
 

Go Back   The RadioReference.com Forums > Software > Digital Voice Decoding Software

Digital Voice Decoding Software For discussion of software applications which decode digital voice formats such as P25, NXDN, MotoTRBO, etc. Please use the HF Digital Signals forum for anything below 30MHz.

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
  #521 (permalink)  
Old 01-23-2013, 11:14 AM
Member
   
Join Date: Mar 2008
Posts: 196
Default

Quote:
Originally Posted by IanWraith View Post
Hi



You need to tune to the frequency that is transmitted from the tower.

A simplex channel is one where the radios transmit on a single frequency directly to each other usually over a small area.
This is the case for the system i am trying to monitor. I know there is one fixed control point but im sure there are some mobile repeaters. There is only one frequency used (at least officially).
Reply With Quote
Sponsored links
  #522 (permalink)  
Old 01-23-2013, 9:42 PM
Mike_G_D's Avatar
Member
   
Join Date: Dec 2002
Location: Escondido, CA
Posts: 872
Default

Quote:
Originally Posted by nycap View Post
Right. the positive line of the sheilded cable is in contact with the 10k resistor before the cap. the negative is grounded where the cap is grounded. problem is i didnt use the 2.2nf cap becuase i couldnt find one. i used the smallest cap i could find (a .01uf) and i was thinking this might not lower the leaky if signal hence the programs failure to sync/decode.

Thanks.
Ahhh! Ok, I didn't know you were talking about a SHUNT cap! Yes, that is for a completely different purpose - it's there to shunt high frequency "gunk" from the discriminator (or the PC) to ground and keep such signals from interfering with correct operation of the PC sound card and radio discriminator. I don't think it's really terribly necessary in most cases as the sound cards are usually pretty well filtered from high frequency signals and the discriminator usually doesn't have an issue with such signals - at least in my experience. Still, it actually IS good practice to use a high frequency shunt filter cap in such a system as long as it is the right value - low enough to attenuate the high frequency noise but not so low so as to attenuate the desired audio frequency range. What might be a problem in your case, then, is that the lower value cap you are using is actually passing too much low frequency audio to ground - I would completely remove that 0.01uF shunt cap and see what you get. It won't kill you to not have it installed.

-Mike
Reply With Quote
  #523 (permalink)  
Old 01-24-2013, 8:08 AM
Señor Member
  RadioReference Database Admininstrator
Database Admin
 
Join Date: Dec 2001
Location: Texas
Posts: 6,008
Default

Quote:
Originally Posted by Mike_G_D View Post
Ahhh! Ok, I didn't know you were talking about a SHUNT cap! Yes, that is for a completely different purpose - it's there to shunt high frequency "gunk" from the discriminator (or the PC) to ground and keep such signals from interfering with correct operation of the PC sound card and radio discriminator. I don't think it's really terribly necessary in most cases as the sound cards are usually pretty well filtered from high frequency signals and the discriminator usually doesn't have an issue with such signals - at least in my experience.
Vintage Uniden models leak lots of IF (around 900 khz). The shunt cap is of benefit to external slicer circuits. It's usually not needed on computer audio inputs.
Reply With Quote
  #524 (permalink)  
Old 01-25-2013, 2:59 AM
Mike_G_D's Avatar
Member
   
Join Date: Dec 2002
Location: Escondido, CA
Posts: 872
Default

Quote:
Originally Posted by Unitrunker View Post
Vintage Uniden models leak lots of IF (around 900 khz). The shunt cap is of benefit to external slicer circuits. It's usually not needed on computer audio inputs.
Ok, that makes sense. Anyway, I really think nycap should omit his shunt cap and then see if his levels improve - I think they will. There still may be other problems, of course, but that should help.

-Mike
Reply With Quote
  #525 (permalink)  
Old 01-27-2013, 9:00 PM
Forts's Avatar
Mentor
  RadioReference Database Admininstrator
Database Admin
Audio Feed Provider
Audio Feed Provider
 
Join Date: Dec 2002
Location: Strathroy, Ontario Canada
Posts: 4,012
Default

This was posted on another forum and I thought I would share it here... A DMRDecode user in Texas came across a system which he believes is now using RAS. He says this shows up before every transmission:

FID=16 11000010000010010010000100000000000000000000000000 00000000000000

I haven't come across any systems using the new security features yet in my area, so I really can't say what it is he may have found.
__________________
Middlesex County/Strathroy-Caradoc Fire Paging Alerts: http://groups.google.com/group/middlesex-fire
Reply With Quote
Sponsored links
  #526 (permalink)  
Old 01-28-2013, 3:14 AM
IanWraith's Avatar
Member
   
Join Date: Sep 2010
Location: ianwraith@gmail.com
Posts: 269
Default

Hi Forts
Cheers for that. It will be interesting to see if that starts to appear more often in other systems.

Regards

Ian
Reply With Quote
  #527 (permalink)  
Old 01-29-2013, 3:37 PM
Member
  Shack Photos
Shack photos
 
Join Date: Nov 2009
Location: Ontario, Ca.
Posts: 41
Default RAS

I see the same thing here also 1100000…... ect I also see this:
CACH : TACT Ch 1 Continuation fragment of LC
Slot Type : Colour Code 13 CSBK
Capacity Plus CSBK : CSBKO=62
Activity Update : LCN 4 is the Rest Channel
11000100000000000000000000000000000000000000000000 00000000000000
Reply With Quote
  #528 (permalink)  
Old 01-31-2013, 1:49 PM
AZScanner's Avatar
Member
   
Join Date: Dec 2002
Location: Somewhere in this room. Right now, you're very cold.
Posts: 3,194
Default

This may or may not already have been posted (my apologies if it has) but when I run this program I get an error that says something to the effect of "Cannot find the main class, exiting". Anyone else run into that and if so, how did you fix it?

Thanks,
-AZ
__________________
Author of ActiveEMS - Phoenix Fire Now Free!
Coming soon: http://phoenixfirevideos.net
Incident Notification now in Beta on Twitter: @PhoenixFireVids
Reply With Quote
  #529 (permalink)  
Old 02-08-2013, 10:27 AM
Member
   
Join Date: May 2009
Posts: 4
Default simplex data

Hello Ian, I have got a question about my technical problem.
I can not recived simplex data with DMR JAVA program.
User in our city have not a repeater. Can you help me???
Thank you. Bye, James
Reply With Quote
Sponsored links
  #530 (permalink)  
Old 02-08-2013, 10:37 AM
IanWraith's Avatar
Member
   
Join Date: Sep 2010
Location: ianwraith@gmail.com
Posts: 269
Default

Hello James

I'm afraid that at the moment DMRDecode doesn't support simplex DMR.

Sorry

Ian
Reply With Quote
  #531 (permalink)  
Old 02-08-2013, 5:08 PM
AZScanner's Avatar
Member
   
Join Date: Dec 2002
Location: Somewhere in this room. Right now, you're very cold.
Posts: 3,194
Default

Hi Ian,

Any chance you could post an answer to my question? I'm sure I'm doing something stupid - to me Java is something I pour into a mug and drink in the morning. But I'd really like to give your program a try.

Thank you,
-AZ
__________________
Author of ActiveEMS - Phoenix Fire Now Free!
Coming soon: http://phoenixfirevideos.net
Incident Notification now in Beta on Twitter: @PhoenixFireVids
Reply With Quote
  #532 (permalink)  
Old 02-08-2013, 5:10 PM
Forts's Avatar
Mentor
  RadioReference Database Admininstrator
Database Admin
Audio Feed Provider
Audio Feed Provider
 
Join Date: Dec 2002
Location: Strathroy, Ontario Canada
Posts: 4,012
Default

Quote:
Originally Posted by AZScanner View Post
Hi Ian,

Any chance you could post an answer to my question? I'm sure I'm doing something stupid - to me Java is something I pour into a mug and drink in the morning. But I'd really like to give your program a try.

Thank you,
-AZ
I've never seen that one. What OS and Java version are you using?
__________________
Middlesex County/Strathroy-Caradoc Fire Paging Alerts: http://groups.google.com/group/middlesex-fire
Reply With Quote
  #533 (permalink)  
Old 02-08-2013, 5:16 PM
AZScanner's Avatar
Member
   
Join Date: Dec 2002
Location: Somewhere in this room. Right now, you're very cold.
Posts: 3,194
Default

Quote:
Originally Posted by Forts View Post
I've never seen that one. What OS and Java version are you using?
It's a windows 7 box. I have no idea what version of Java. I can check it later on and let you know. I'll try updating or reinstalling it to see if that helps.

-AZ
__________________
Author of ActiveEMS - Phoenix Fire Now Free!
Coming soon: http://phoenixfirevideos.net
Incident Notification now in Beta on Twitter: @PhoenixFireVids
Reply With Quote
  #534 (permalink)  
Old 02-08-2013, 5:45 PM
Forts's Avatar
Mentor
  RadioReference Database Admininstrator
Database Admin
Audio Feed Provider
Audio Feed Provider
 
Join Date: Dec 2002
Location: Strathroy, Ontario Canada
Posts: 4,012
Default

That could be your problem. Ian updated the Java requirements a few months back.
__________________
Middlesex County/Strathroy-Caradoc Fire Paging Alerts: http://groups.google.com/group/middlesex-fire
Reply With Quote
  #535 (permalink)  
Old 02-08-2013, 6:35 PM
MikeOxlong's Avatar
Global DB Admin/Senior Mod
  RadioReference Database Admininstrator
Database Admin
 
Join Date: Jun 2001
Location: Central Ontario
Posts: 6,713
Default Java program to decode DMR

You can usually type java -version to see what's installed.
__________________
Mike.

Sorry but I don't accept PM's. Please use email instead.
Reply With Quote
Sponsored links
  #536 (permalink)  
Old 02-08-2013, 10:13 PM
AZScanner's Avatar
Member
   
Join Date: Dec 2002
Location: Somewhere in this room. Right now, you're very cold.
Posts: 3,194
Default

OK guys, now I'm getting annoyed by this thing.

I downloaded the latest version of the program here: https://github.com/IanWraith/DMRDecode/downloads

I copied it to a folder on my hard drive called DMRDecode.

I updated Java to version 6 Update 17.

I double click the Jar file in the folder.

I get the following error from something called the Java Virtual Machine Launcher: Could not find the main class:com.dmr.DMRDecode. Program will exit.

Obviously I'm doing something wrong as it works for everyone else but me... the question is what??

Thanks for the help, guys
-AZ
__________________
Author of ActiveEMS - Phoenix Fire Now Free!
Coming soon: http://phoenixfirevideos.net
Incident Notification now in Beta on Twitter: @PhoenixFireVids
Reply With Quote
  #537 (permalink)  
Old 02-08-2013, 10:30 PM
Forts's Avatar
Mentor
  RadioReference Database Admininstrator
Database Admin
Audio Feed Provider
Audio Feed Provider
 
Join Date: Dec 2002
Location: Strathroy, Ontario Canada
Posts: 4,012
Default

I'm running Oracle Java version 7 on my machines. Maybe give that a try?

Download Free Java Software
__________________
Middlesex County/Strathroy-Caradoc Fire Paging Alerts: http://groups.google.com/group/middlesex-fire
Reply With Quote
  #538 (permalink)  
Old 02-08-2013, 10:46 PM
AZScanner's Avatar
Member
   
Join Date: Dec 2002
Location: Somewhere in this room. Right now, you're very cold.
Posts: 3,194
Default

Well why the heck didn't my Java updater thing update to version 7? I literally just ran the update a little while ago. Oh well,downloading now I'll let you know if it worked. Thanks for the info.

-AZ

Edit: That was it, now it runs! Thank you!
__________________
Author of ActiveEMS - Phoenix Fire Now Free!
Coming soon: http://phoenixfirevideos.net
Incident Notification now in Beta on Twitter: @PhoenixFireVids

Last edited by AZScanner; 02-08-2013 at 10:51 PM..
Reply With Quote
  #539 (permalink)  
Old 02-22-2013, 9:05 AM
Member
   
Join Date: Mar 2008
Posts: 196
Default

Quote:
Originally Posted by IanWraith View Post
Hi



You need to tune to the frequency that is transmitted from the tower.

A simplex channel is one where the radios transmit on a single frequency directly to each other usually over a small area. There are a small number of such setups here in the UK but the vast majority of systems use a repeater.

Regards

Ian
I just want to thank you. Hats off to you for such an awsome program. After putting in the 2.2nf cap in its been working very well.

After monitoring for a while now i have some new questions;

(1) what is the "logical link"; and (2) why is it that sometimes i hear the digital signal but nothing happens in the decoder?

Thanks again.
Reply With Quote
  #540 (permalink)  
Old 02-22-2013, 10:26 AM
IanWraith's Avatar
Member
   
Join Date: Sep 2010
Location: ianwraith@gmail.com
Posts: 269
Default

Hello Nycap

Firstly glad you like the program. As for your questions ..

1) The word "logical link" I must admit I don't know. I have followed the wording used in the official ETSI specs without fully understanding parts of it.

2) There are many reasons for this. Sometimes the signal is so strong it is distorting in your scanner and sometimes there are reflections in the signal which really mess up the demodulation of the bits.

Sorry I can't help more.

Regards

Ian
Reply With Quote
Reply

Tags
dmr, sticky, trbo

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -5. The time now is 9:28 AM.


Powered by vBulletin® Version 3.8.2
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
All information here is Copyright 2012 by RadioReference.com LLC and Lindsay C. Blanton III.Ad Management by RedTyger
Copyright 2011 by RadioReference.com LLC Privacy Policy  |  Terms and Conditions