RPi 3 & RTL-SDR/OP25?

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maus92

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maus92

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Howell . not much to gleen from this. I basically had to find and ask others who had scanners what freq law enforment was using. i still would like to know if I can add digital freq. to this op25. as most of the EMS services are not using p25 . still analog.
I'm a bit unclear what you are asking, but it appears from the RRDB data that Howell County uses the MI statewide system for law enforcement and an EMS user. The cch that you have set up in OP25 appears that it would provide access to those TGs. Howell area agencies appear to make extensive use of VHF conventional frequencies for their sheriff, fire, and EMS services. OP25 cannot receive conventional / analog VHF. However, GQRX can.
 

huskerswon

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huskerswon said:
Thank You for giving some instructions and keeping everything updated for the Pi install. I have a Pi3B+ and the Nooelec Smart. I have everyting up and running with audio. I am having issues with voice groups below the control frequency. I know that there is voice channels below the CC because i can see them on GQRX. I have seen 2 or 3 of these below my CC Freq. My CC is 769.16875. See attached. when I run the "./rx.py --args 'rtl=0' -N 'LNA:36' -S 2400000 -f 769.16875e6 -o 25000 -T trunk.tsv -V -w -2 -U 2> stderr.2" Only the talk group high than the CC show up. I have let this run for hours and never see a Talk group below my CC..
any help?

The CC is 769.16875
 

huskerswon

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I'm a bit unclear what you are asking, but it appears from the RRDB data that Howell County uses the MI statewide system for law enforcement and an EMS user. The cch that you have set up in OP25 appears that it would provide access to those TGs. Howell area agencies appear to make extensive use of VHF conventional frequencies for their sheriff, fire, and EMS services. OP25 cannot receive conventional / analog VHF. However, GQRX can.
This is why i am confused?? The have both systems. i think it must be a mess trying to deal with both. I am using the GQRX and looking at looking at the CCh of 769.16875 and I see waterfall trafffic around the 767.865 area. I input that into gqrx to see if I can hear any audio on that ..it is not audible. So I know it is a TG. just perplexed.. they must have some code ..
 

sallen07

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This is why i am confused?? The have both systems. i think it must be a mess trying to deal with both. I am using the GQRX and looking at looking at the CCh of 769.16875 and I see waterfall trafffic around the 767.865 area. I input that into gqrx to see if I can hear any audio on that ..it is not audible. So I know it is a TG. just perplexed.. they must have some code ..
Here are the four frequencies in the database for the site you are listening to:

769.16875c769.66875769.91875770.16875

As you can see, the control channel is the lowest of the four frequencies. Whatever you are seeing down around 767.865 would appear to be unrelated to this system.
 

maus92

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This is why i am confused?? The have both systems. i think it must be a mess trying to deal with both. I am using the GQRX and looking at looking at the CCh of 769.16875 and I see waterfall trafffic around the 767.865 area. I input that into gqrx to see if I can hear any audio on that ..it is not audible. So I know it is a TG. just perplexed.. they must have some code ..
767.xxx is out of band for public safety systems. 769 is the floor.
 

maus92

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huskerswon said:
Thank You for giving some instructions and keeping everything updated for the Pi install. I have a Pi3B+ and the Nooelec Smart. I have everyting up and running with audio. I am having issues with voice groups below the control frequency. I know that there is voice channels below the CC because i can see them on GQRX. I have seen 2 or 3 of these below my CC Freq. My CC is 769.16875. See attached. when I run the "./rx.py --args 'rtl=0' -N 'LNA:36' -S 2400000 -f 769.16875e6 -o 25000 -T trunk.tsv -V -w -2 -U 2> stderr.2" Only the talk group high than the CC show up. I have let this run for hours and never see a Talk group below my CC..
any help?

The CC is 769.16875
The voice channels for the system you are monitoring are above 769.16875. Not sure what you mean by "voice groups." There are "talkgroups" that can be assigned to any traffic channel of the system. OP25 manages the frequencies (traffic channels,) you manage the talkgroups.
 
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