DSD on a P25 Simulcast System?

So I'm using DSD+ with an RTLSDR dongle. I am not getting super great decodes, even after running dsdtune. My guess is that this is because we have a simulcast system here (this is Ohio MARCS-IP).

Is there anything special I can do to help with this?

Right now, my setup is just Unitrunker feeding audio from the rtlsdr right into DSDPLUS with virtual audio cable.

- Dave

dandrzejewski said:

So I'm using DSD with an RTLSDR dongle. I am not getting super great decodes, even after running dsdtune. My guess is that this is because we have a simulcast system here (this is Ohio MARCS-IP).

Is there anything special I can do to help with this?

Right now, my setup is just Unitrunker feeding audio from the rtlsdr right into DSDPLUS with virtual audio cable.

- Dave

Click to expand...

yes there is a great alternative if you REALLY want good simulcast reception: download & install OP25 instead. From personal experience I can attest that it WILL provide the best-available simulcast reception (i.e. much better than any hardware scanner), the only thing better is an agency radio...

Is it possible to get OP25 running in Windows? My setup is an OSX host with a Windows VM where I run all this stuff.

Or, is there software like UniTrunker that will run on OSX? That way, I could build OP25 right on OSX.

Also, I should mention: It's DSD+, not DSD. Don't know why I wrote that

dandrzejewski said:

Is it possible to get OP25 running in Windows? My setup is an OSX host with a Windows VM where I run all this stuff.

Or, is there software like UniTrunker that will run on OSX? That way, I could build OP25 right on OSX.

Click to expand...

Not sure, you should check the ongoing thread addressing install-type questions in excruciating detail. Most people seem to report the best outcomes using "native" Linux Mint 1.17 (that's what I run it on), or alternatively Ubuntu. Many people have reported difficulties even running linux as a virtual machine, let alone Windows. It is NOT a "one-click" install, but you can get it working if you want it bad enough. Also for OP25, you only need one dongle and you don't need any other software to get it fully operational (although you won't be able to pick up voice frequencies outside the 2.4 MHz sample range of a standard RTL SDR stick, which would be true of any decoding software you might use).

natedawg1604 said:

(although you won't be able to pick up voice frequencies outside the 2.4 MHz sample range of a standard RTL SDR stick, which would be true of any decoding software you might use).

Click to expand...

That's partially true, but only if you use a center frequency in the trunking config file. If the center frequency is omitted, then it'll re-tune the device to the desired frequency along with additional offset if specified.

PiccoIntegra said:

That's partially true, but only if you use a center frequency in the trunking config file. If the center frequency is omitted, then it'll re-tune the device to the desired frequency along with additional offset if specified.

Click to expand...

Wow I didn't realize that, now I like OP25 even better. Is it simply a matter of "fast" re-tuning?

fast? *shrug*

It's not too slow..

I also monitor a simulcast P25 system, and for some reason I get much better decodes tuning the voice dongle with SDRSharp than I do with Unitrunker.