Hi, just a quick update. I tried changing the tone amplitude and haven't been able to find any number that helps. Basically these are alert tones prior to an announcement or page out. The tones are still very harsh and loud compared to the audio that's being received. Is there another setting I can try to help soften or minimize the tones?
OP25 RTL-SDR No Audio OP25 Ubuntu
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boatbod
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There's no reason that modifying the multiplier in the c++ source where the tones are generated (software_imbe_decoder.cc) wouldn't directly affect the amplitude of the tones unless for some reason you haven't actually built and installed the new library code.
I'd also go as far as saying that the default settings are pretty comparable to the amplitude and "harshness" of the tones generated by a real /\/\ subscriber radio on my local phase 2 system. If anything, op25 is perhaps slightly lower in amplitude...
Clearly I'm doing something wrong because it made absolutely no difference at all. I will do a git-pull to make sure I have the latest version and go back through to make sure I'm doing the right thing. Thanks for your patience
(I have two subscriber units and the tones on either of my machines running op25 are wayyyy harsher than the subscriber units)
boatbod
Member
Clearly I'm doing something wrong because it made absolutely no difference at all. I will do a git-pull to make sure I have the latest version and go back through to make sure I'm doing the right thing. Thanks for your patience
(I have two subscriber units and the tones on either of my machines running op25 are wayyyy harsher than the subscriber units)
What happens if you set the multiplier to 0? (software_imbe_decoder.cc, line 1124, column 22) Logic requires the tones to completely mute. If they don't, you aren't getting the changes built and installed correctly.
I think I'm still doing something wrong. I have completed a git pull and sudo make install with no errors. The excerpt below is from my software_imbe_decoder.cc file and there is absolutely no difference. I know it's me but I'm not sure what I'm messing up. Everything works wonderfully otherwise!
// Synthesize tones
step1 = 2 * M_PI * freq1 / 8000;
step2 = 2 * M_PI * freq2 / 8000;
amplitude = _AD * 0; // make adjustment to overall tone amplitude here
for (en = 0; en<=159; en++) {
sample = amplitude * (sin((*_n) * step1)/2 + sin((*_n) * step2)/2);
samples->push_back(sample);
(*_n)++;
boatbod
Member
I think I'm still doing something wrong. I have completed a git pull and sudo make install with no errors. The excerpt below is from my software_imbe_decoder.cc file and there is absolutely no difference. I know it's me but I'm not sure what I'm messing up. Everything works wonderfully otherwise!
// Synthesize tones
step1 = 2 * M_PI * freq1 / 8000;
step2 = 2 * M_PI * freq2 / 8000;
amplitude = _AD * 0; // make adjustment to overall tone amplitude here
for (en = 0; en<=159; en++) {
sample = amplitude * (sin((*_n) * step1)/2 + sin((*_n) * step2)/2);
samples->push_back(sample);
(*_n)++;
After you edited the source file what steps did you take before running op25? Something like this is needed:
Code:
cd ~/op25/build
make
sudo make installI was missing the "make" part of the process. Thanks for calling that out! Interestingly enough, I tried that and it made no difference whatsoever but it's a bit of a moot point now. We just switched to Phase II in my county and the audio and tones are MUCH calmer. (with no change on my end to 3 different PC/VM's) I'm not so sure it wasn't something with the system before. Now we are doing paging tones over Phase II and the tones are clear and calm as well as the alert tones. I have to say how appreciative I am to Graham for making such a quality software. OP25 has been working flawlessly on the new Phase II configuration and continues to amaze me. Thanks again!!!
boatbod
Member
FDMA does not encode tones in the same manner as TDMA and it is sent by the originating system. The op25 tone regeneration code is specifically for phase 2 only.
Ok, thanks! I am noticing that the audio cuts out on the new system. It's choppy or pulsing the best I could describe. I've tried pulling down the latest version and replacing the sockaudio.py on one of my pc's but all 3 are doing the same thing and it didn't change anything on the 1 I tried. My plotmap shows I have good signal so I'm thinking that it's just a setting or variable. I've adjusted the sample size as well and it didn't seem to make that much of a difference. I notice that tones will come across perfect for the whole duration pretty much every time but audio seems to pass then stop then pick back up during the transmission. Keep in mind, this system is very new and still evolving so it's quite possible that there are changes being made daily if not more frequently
boatbod
Member
Ok, thanks! I am noticing that the audio cuts out on the new system. It's choppy or pulsing the best I could describe. I've tried pulling down the latest version and replacing the sockaudio.py on one of my pc's but all 3 are doing the same thing and it didn't change anything on the 1 I tried. My plotmap shows I have good signal so I'm thinking that it's just a setting or variable. I've adjusted the sample size as well and it didn't seem to make that much of a difference. I notice that tones will come across perfect for the whole duration pretty much every time but audio seems to pass then stop then pick back up during the transmission. Keep in mind, this system is very new and still evolving so it's quite possible that there are changes being made daily if not more frequently
What hardware are you running on?
What command line params are you using to start rx.py?
Can you post screen captures of the constellation and mixer plots please.
I think I may have figured it out. I lowered the sample rate to the lowest per your recommendation on another thread and I also didn't have the GNU Plot running on the screen. I also made sure that there were no other running apps at the time. I think both of my laptops are so low spec that they just can't handle it.
The command I am using is ./rx.py --args 'rtl' -N 'LNA:47' -S 56700 -f 155.4300e6 -o 25000 -q -2 -T trunk.tsv -V -2 -U 2> stderr.2
Seems to be running real well now on both laptops and not missing much. (Now if I could only get my PSR-800 to decode it ugh, what a nightmare)
The command I am using is ./rx.py --args 'rtl' -N 'LNA:47' -S 56700 -f 155.4300e6 -o 25000 -q -2 -T trunk.tsv -V -2 -U 2> stderr.2
Seems to be running real well now on both laptops and not missing much. (Now if I could only get my PSR-800 to decode it ugh, what a nightmare)
boatbod
Member
I gave up with my PSR-800. It's totally hopeless with simulcast.
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