Greeting all, I am able to establish a op25 Receiver but, it does not tune to the correct frequency, I believe that this is because "[R82XX] No valid PLL values for 2293470628 Hz! r82xx_set_freq: failed=-1" My command line is: ./scope.py --args 'rtl=0,buflen=65536' -g 65 -f 851.18750e6 -N 'LNA:49' -V -v 0 -S 288000 -q 39 -T trunk.tsv I am attaching my trunk.tsv file and the error from Terminal. I also have a concern about the NAC of the group that I want to follow, on RR, the "System ID" is 348, 5A1, and 649. The WACN is BEE00. I am interested in the Cincinnati / Hamilton County system. On the UniTrunker setup, the NAC is showing as 342. Any help would be appreciated. Mel
Hi Mel There are a couple of things going on here. In your trunk.tsv file, your control channel frequency format is incorrect. You don't need to use scientific notation for those entries, so remove the "e6". You are also specifying an offset of 1500, 15000 would be a better choice here. I don't recall the filter width of the demodulator, but you are trying to keep the DC spike out of the channel bandwidth. Maybe 20000 for the offset? In your cincy.tsv file, there is an extra line at the very end, which would throw an error upon parsing that file. The last line needs to be valid talkgroup information. i.e. "59030 Emergency Management Agency" should be the very last line. ./scope.py --args 'rtl=0' -f 851.18750e6 -N 'LNA:40' -V -v 0 -S 960000 -q 39 -T trunk.tsv Try using that command line instead of the one you're using. The LNA gain of 49 is a bit much, and you're probably overloading the signal a bit. The sample rate of 288000 is also not very efficient, 960000 is a much better option. I didn't see any TDMA talkgroups on that system you're monitoring, so the '-2' isn't necessary here. -Scott
Hello Scott, Thanks for the pointers, I cleaned up the trunk.tsv files and added the suggested values; I also removed that blank line in the cincy.tsv file and, using the command line as stated, the Graph came up and displayed. Great progress, at this point, the display in the terminal windows is scrolling "timed out". I was able to use the PPM correction (20) to adjust display to read "Tuning Error" +/- 2400 and then down to - 1200. At PPM setting of 18, the terminal read, +1200. At -19 PPM, the displayed stopped scrolling and, my Constellation appeared to be as desired; "Fine Tuning" in either direction would cause a tuning error. All good until I went to the "Traffic" tab, there were zeros in all the fields ( "rf:syid, rfid, stid") where there should have been numbers, It appears that I can see the traffic and tune he frequency but, I am not breaking the squelch(?) or do not have the correct NAC(?). BTW: I heard only one snippet of audio during the process, so, with everything seemingly to be in the ball park, what key attribute am I missing, is it the correct identifier for the Cincinnati / Ham. Co branch of the Ohio MARCS-IP system or, is it an intellectual thing? Thanks again for getting me oriented, all help is appreciated! Mel
The missing attribute is "Hardware"; a Core2-Duo will not cut the mustard. Mel
Oh. BTW, this is how it looked but the audio was from another scanner. https://youtu.be/PA3JkM8zlBw https://youtu.be/PA3JkM8zlBw
Hi Mel This video looks ok to me. From your initial reply, it looks like you haven't quite got the frequency dead center yet. It is kind of a pain in the ass until you learn your device characteristics. Which RTL device are you using? Based on your PPM setting, I'd wager a guess and say the cheap $10 device. If you're wanting to stay on the budget side of SDR, then I really recommend the $25 rtl-sdr.com dongles. They are stable devices with little to no drift. What method did you use to install GNURadio/OP25? "The missing attribute is "Hardware"; a Core2-Duo will not cut the mustard." That hardware is good enough, it's what I used for my everyday SDR scanner with OP25. -Scott
Scott, I am using the NooElec NESDR Mini for the op25 receiver. The first device that I bought was a cheaper one and then I bought a higher priced NooElec Mini to use with Unitrunker, the NooElec device has a lower noise floor and, it does not drift as much over time as does the cheaper model. To build my op25 receiver, I started with the RR forum article (circa 2014) on running op25 on Windows 7 on VM Ware. I decided to create a bootable a USB stick with GNU Radio Live SDR Environment running on Ubuntu 14.04. After establishing Ubuntu, I went back to the RR forum and used the PYBOMBS install script: Install the OS(assuming Ubuntu or Mint), then open a terminal session and Code: sudo apt-get install git sudo apt-get update Reboot if it asks, otherwise type the following: Code: cd ~/ git clone git://github.com/pybombs/pybombs cd pybombs ./pybombs install gnuradio So, at this point I have it installed but, I continue to read more until I came across, This recipe has been tested on ubuntu 14.04 only, it is likely NOT to work in either 12.04 or 16.04... First, use these commands to install the pre-reqs sudo apt-get update sudo apt-get build-dep gnuradio sudo apt-get install gnuradio gnuradio-dev gr-osmosdr librtlsdr-dev libuhd-dev libhackrf-dev libitpp-dev libpcap-dev git Second, use these commands to build and install OP25: [Note, the mkdir build; cd build; cmake ../; make; sudo make install sequence is a bog-standard form when source-building apps that utilize cmake.] cd ~ git clone git://op25.osmocom.org/op25.git cd op25 mkdir build cd build cmake ../ make sudo make install sudo ldconfig So Scott, after I installed and understood it, I started working with the trunk.tsv and the cincy.tsv to make it work for me. That's when I got you involved. Mel
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justeu.badd＠gmail.com [op25-dev] -
verymetl＠hotmail.com [op25-dev]