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  #401 (permalink)  
Old 05-26-2018, 5:44 PM
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PulseAudio is not required, but if it's running, it would need to be configured correctly. op25 can send audio directly to ALSA, assuming your audio device works with ALSA, and it may suffer less jitter that way.
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Old 05-26-2018, 6:09 PM
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When you did the successful "aplay" what audio device did you use? If you didn't explicitly set the audio device the 'default' device will be used, and that is usually sufficient. Try removing the both the "-O audio_out" and "-w" parameters and retry.

ETA: looking back at your posted command line it looks like your "-T" parameter is commented out (with "#") along with the -O and -w. If this is so, you won't get voice because the op25 app is not in trunking mode. You definitely need the "-T trunk.tsv".

Last edited by boatbod; 05-26-2018 at 7:15 PM..
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  #403 (permalink)  
Old 05-26-2018, 9:06 PM
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Thanks all. I have made the suggested changes however the system appears to be offline. I had seen this happen last weekend as well - this is a new deployment in early stages with only active users during “first shift” timeframe.

I will recheck in Tuesday when it should be back online.

I do have a question on what is displayed in the web GUI. There are two frequencies displayed on the line between the NAC and the tsbks count. One I recognize as the control channel frequency that I coded but I don’t recognize the second frequency. Is that another control channel that the system itself is reporting? Should I enclose both frequencies as “853.7875,808.7875” in the trunk.tsv?

Also, given limited resources on the Pi, would I be better off removing PulseAudio and sticking with ALSA now that I know the lack of a -T specification would result in no audio decoding. I don’t plan any other role for the Pi that would need to share audio output.

Thanks again for guiding me thru a bit of a learning curve.

Glenn


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  #404 (permalink)  
Old 05-26-2018, 9:55 PM
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Quote:
Originally Posted by gskroll View Post
Should I enclose both frequencies as “853.7875,808.7875” in the trunk.tsv?
You would not need both. One is the frequency that the repeater is transmitting on the while the other is the frequency that the repeater is listening on. For 800 MHz channels, there is a 45 MHz offset. https://wiki.radioreference.com/index.php/Offset


Quote:
Also, given limited resources on the Pi, would I be better off removing PulseAudio and sticking with ALSA
That is the recommendation, even on beefier hardware. I was where you were once and remember pavucontrol helping me figure out at the time that, while aplay was working, op25 (i.e., python) was sending its audio somewhere else.
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  #405 (permalink)  
Old 05-26-2018, 10:03 PM
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Quote:
Originally Posted by SpugEddy View Post
QUESTION: Is there a better or easier program that I can install and run from the Desktop? P25 would be nice to have since I think I still have access to State Police for a little bit longer. Mainly will be used on 10, 11, 2 meterand 63cm bands

What are you looking to do? There are few very P25 amateur radio systems. Are you looking to receive an existing system (perhaps the state police based on your comment above), or play with the tx functions in op25 to transmit on amateur bands you listed?
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  #406 (permalink)  
Old 05-26-2018, 10:26 PM
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Quote:
Originally Posted by apu View Post
You would not need both. One is the frequency that the repeater is transmitting on the while the other is the frequency that the repeater is listening on. For 800 MHz channels, there is a 45 MHz offset. https://wiki.radioreference.com/index.php/Offset


That is the recommendation, even on beefier hardware. I was where you were once and remember pavucontrol helping me figure out at the time that, while aplay was working, op25 (i.e., python) was sending its audio somewhere else.


Ok - thanks again for your help. I will remove PulseAudio and concentrate on getting ALSA working to impose less overhead on the Pi.

I had done additional testing temporarily removing the -T parm from the rx.py command line and found that the system is still on the air - I had mistyped the NAC.

I added the -T part back after correcting the NAC and the web GUI is filling in system info and clocking up the tsbks count.

I am suspicious that Sunday and Monday won’t see much, if any, traffic given the nature of the services using the new system at this time. I should be able to determine if the -T change has me up and running Tuesday if not earlier.

Thanks for your patience.

Glenn


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  #407 (permalink)  
Old 05-26-2018, 11:08 PM
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Quote:
Originally Posted by apu View Post
What are you looking to do? There are few very P25 amateur radio systems. Are you looking to receive an existing system (perhaps the state police based on your comment above), or play with the tx functions in op25 to transmit on amateur bands you listed?
Strictly for listening on the mentioned bands. 10, 11, 2 meters
and a lot of 63 cm bands. One thing i want to do is monitor
a local repeater because it has a very sporadic time out timer.
(You can key the mic and start talking and the repeater cuts off.
Sometimes it doesn't cut off and other times it cuts off 20 seconds
into your keydown)

And yes NJSP is still using some P25. Works good with my Windows
computer with UniTrunker , but I'd like a separate computer all together
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  #408 (permalink)  
Old 05-27-2018, 2:09 AM
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Quote:
Originally Posted by SpugEddy View Post
Strictly for listening on the mentioned bands. 10, 11, 2 meters and a lot of 63 cm bands.
Are there P25 systems in those bands in your area? Otherwise, rtl_fm may be more appropriate.

Quote:
And yes NJSP is still using some P25. Works good with my Windows computer with UniTrunker , but I'd like a separate computer all together
The NJSP system or the NJICS system? Some talkgroups are on both but they are separately systems. op25 is for P25 trunked systems (or, recently, single P25 channels) not non-P25 monitoring.
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  #409 (permalink)  
Old 05-28-2018, 8:27 AM
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I happened to catch some trash collectors’ traffic on the new Portland Maine P25 system this morning (yes they are working on Memorial Day!).

Thanks to all for helping me to get the audio issue resolved.

Glenn


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  #410 (permalink)  
Old 05-28-2018, 9:46 AM
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Quote:
Originally Posted by apu View Post
op25 is for P25 trunked systems (or, recently, single P25 channels) not non-P25 monitoring.
Support for monitoring DMR, YSF and DSTAR was added last year, as announced on Christmas, 2017...

Max
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  #411 (permalink)  
Old 05-28-2018, 7:54 PM
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Max, Thanks for correcting me. And all your work (and boatbod's work) in the constant improvements.
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  #412 (permalink)  
Old 06-17-2018, 5:05 AM
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What I'd like to do... is make a Rpi based device, in a small package with a 3" or so display, about the size of the home patrol, which seems very doable...

I only have 2 agencies/systems I care about monitoring, but in multiple sites (and multiple NACs).

I would want physical buttons... Pressing button 1 would kill the current rx.py session and relaunch the rx.py with different command arguments, to select a different site/system.

For example, Button 1 would be 'City PD' , which would have files for the city talkgroups and associated sites.Button 2 would be City FD, Button 3 would be 'County FD' etc.... with probably about 6 buttons for good measure...

So, of course, the issue becomes, I have zero experience with the Pi. I would not be selling it, just want for my own tinkering, FYI...

A couple questions...


So, how would one modify the output of the program to display only pertinent info, Ie talkgroup it's currently on.... and system name? On a 3.5" display, the small text would be 2 pixels high, heh. I wouldn't necessarily need freq. info but a small secondary display, like a 2 line OLED display would be nifty.

Also, how would one use buttons to launch scripts? Obviously through the GPIO pins, but I'm not sure how you would make it so that a program was memory resident and ran REGARDLESS of what screen/program you're in, as it appears that most scripts/programs run in a shell.

Speaker audio would be from the speaker port, through an amplified speaker.

Pointers in the right direction would be greatly appreciated.
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  #413 (permalink)  
Old 06-17-2018, 1:51 PM
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Quote:
Originally Posted by jparks29 View Post
So, how would one modify the output of the program to display only pertinent info, Ie talkgroup it's currently on.... and system name? On a 3.5" display, the small text would be 2 pixels high, heh. I wouldn't necessarily need freq. info but a small secondary display, like a 2 line OLED display would be nifty..
I'd suggest either writing your own custom web terminal handler. With that you could do everything you need using a touch screen rather than physical buttons, which is probably easier anyway. You'll need to familiarize yourself with python and also the way in which op25 passes messages between itself. Use the example of the fine-tune adjustment buttons to learn how the various parts interact.
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  #414 (permalink)  
Old 06-24-2018, 9:37 PM
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Default Start from Scratch

Does anyone have any instructions on how to start from Scratch? What Ubuntu to use, how to install everything for the RTL-SDR?

I have a Raspberry Pi3 and have seen some threads where people have them working, however I do need "some" basic instructions.

I look forward to anyone that is kind enough to help.

Thank you
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  #415 (permalink)  
Old 06-25-2018, 3:31 PM
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Quote:
Originally Posted by atms169 View Post
Does anyone have any instructions on how to start from Scratch? What Ubuntu to use, how to install everything for the RTL-SDR?

I have a Raspberry Pi3 and have seen some threads where people have them working, however I do need "some" basic instructions.

I look forward to anyone that is kind enough to help.

Thank you
Install Raspbian and get it running.
sudo apt-get install git
git clone github.com/boatbod/op25 ~/op25
cd ~/op25
./install.sh
Configure and adjust tuning
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  #416 (permalink)  
Old 06-28-2018, 10:02 PM
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Default Raspberry Pi3 and RTL-SDR

Thank you
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  #417 (permalink)  
Old 06-29-2018, 5:58 PM
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Hello,

So I have op25 running, and it awesome, everything is good to go. I have two questions. Is there any way to record to a wav file what Op25 is decoding. I know trunk-recorder is out there, but I am having trouble getting it to record (only getting 44 byte .wav files). my second question is I know that you can redirect to wireshark. So I have been reading that you need to patch wireshark in order to correctly view the packets. The links on the instructions are old, and do not work, so has anyone had luck doing that recently , if so do you have instructions OR does the newer version of wireshark handle the P25 packets?

Thank you!
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  #418 (permalink)  
Old 06-29-2018, 8:19 PM
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I'm a ham radio operator and I'm trying to figure out how to use rx.py output to Wireshark (OP25). I want to see the packet stream.

I am also using a Raspberry Pi3.

So far, I can get the rx.py to run but can't figure out how to monitor the packets in Wireshark.

Any help apprecaited


Quote:
Originally Posted by BigRon View Post
I'm curious to know if the RPi3 has enough "horsepower" to use Gnuradio/OP25 to decode a p25 trunked system using RTL-SDR. I haven't been able to find minimum hardware requirements and curious if this would work.
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  #419 (permalink)  
Old 06-30-2018, 5:22 PM
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Quote:
Originally Posted by jparks29 View Post
Is this too much to ask of a Rpi3?

*Single dongle
*LCD with Touch GUI using scripts to launch different system config files(through Raspbian)
*An OSD button that sends q command to quit before launching another script
*Audio output


Essentially, I wanna push a button (Or link to a script, in his case) to listen to either a system or an individual talkgroup, which I can configure via individual scripts...

I'm thinking something HomePatrol sized with a small touch LCD, that's essentially only for one system, but able to fairly quickly select a preset group of TGs, or individual talkgroups (again, through multiple customized scripts/config files).

What about a 'minimalist' output display that, in large font, displays the TG, the TG alpha, and the radio ID?
My friend added a small oled 128x32 display...
Advancing Ham Radio.. different ideas: Listening to local 700 MHz Simulcast public safety cheaply
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  #420 (permalink)  
Old 06-30-2018, 9:07 PM
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Quote:
Originally Posted by kb9mwr View Post
Didn't see any info on configuring the LED display, but that's perfect
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