SDRTrunk vs. OP25?

[dave3825]

I'm listening to a p25 phase 2 system in CT with OP25 with 1 dongle, and works great.

What system is that and what site do you monitor?

SDRTrunk requires at least 2 dongles

Not always. I have a system that spans 1.97mhz and Sdrtrunk, Op25 and DSDPlus all do awesome with just one Nooelec dongle running @ 2.4mhz. Right now I am running my Airspy mini at 6mhz and its following 2 different phase 2 systems without missing a beat in Sdrtrunk. 4.075mhz. I do have another system in Sdrtrunk that spans 2.4375mhz and it seems to do good with the sample rate set to 2.56.

For the OP, if its the Montgomery County, MD system, he would need more than one dongle as those freqs span 2.725mhz.

 

[dimab]

What system is that and what site do you monitor?

CLMRN - 031 (1F) Troop L Simulcast Litchfield

 

[jjbllitz]

Thanks LethalDosage. Never thought about the priority. I changed it temporarily this afternoon and at the time it seemed to help. At least for the few minutes I was able to watch, I saw no control or voice channel drops. Will continue to monitor.

Boatbod, I am liking OP25 more and more as well. I have it sounding much better. Played with multi_rx last night, and could not get it to run for just one of the channels, but I'll keep digging with it. Have another SDR coming tomorrow.

 

[boatbod]

Thanks LethalDosage. Never thought about the priority. I changed it temporarily this afternoon and at the time it seemed to help. At least for the few minutes I was able to watch, I saw no control or voice channel drops. Will continue to monitor.

Boatbod, I am liking OP25 more and more as well. I have it sounding much better. Played with multi_rx last night, and could not get it to run for just one of the channels, but I'll keep digging with it. Have another SDR coming tomorrow.

multi_rx.py is just as happy running a single channel as for multiple. It's a complete replacement for rx.py driven by cfg.json vs a veritable mountain of command line args.

 

[ScannerDude244]

will a raspberry Pi 4 2GB be able to handle multi_rx.py?

 

[boatbod]

will a raspberry Pi 4 2GB be able to handle multi_rx.py?

Yes, it works fine. The limiting factor is going to be the bandwidth of the SDR and the number of simultaneous streams since both consume cpu cycles. 3Mhz Airspy Mini is ok, 6MHz Airspy Mini is cpu-intensive. 10Mhz Airspy R2 is a bit too much. OTOH multiple 1Mhz RTL are fine.