SDR Fire Tone Alerting

[Bjc123]

Hello, hope everyone is well.

Not sure if this is the right forum thread but,

I am looking for some software or an app where I could get an alert when it detects the VHF tones.
Preferably compatible with SDR.

Could someone point me in the right direction? Or let me know if this is even possible?

Thanks for the help,
Bjc123

 

[boatbod]

Hello, hope everyone is well.

Not sure if this is the right forum thread but,

I am looking for some software or an app where I could get an alert when it detects the VHF tones.
Preferably compatible with SDR.

Could someone point me in the right direction? Or let me know if this is even possible?

Thanks for the help,
Bjc123

Most of what I've seen (e.g. TwoTone Detect) are designed to work on a sound card not straight SDR.

I see that you're located in Montgomery County, MD. If I recall, they have recently switched over to P25 Ph2 system and are paging over the P25 system which means the tones are being transmitted as special AMBE+ codewords rather than encoded analog. You might be able to loop the output from an SDR app back to TTD but I don't think there is a native solution yet.

 

[Bjc123]

Yeah, Since posting I have found an old post that had the old TwoTone Detect.

I am now trying to virtually pipe the audio from my SDR Software to the TwoTone Detect.

Very, Very, cumbersome way of working around this issue but hopefully, fingers crossed, I can eventually get it to work.

I will update later if I ever get it to work lol

Thanks,
Bjc123

 

[Bjc123]

Update: I was eventually able to virtually route audio from SDR# into TwoToneDetector V71. Not a super complex process but definitely took some time. The tones worked for at least one station. And emails did work so I'm excited.

 

[boatbod]

Update: I was eventually able to virtually route audio from SDR# into TwoToneDetector V71. Not a super complex process but definitely took some time. The tones worked for at least one station. And emails did work so I'm excited.

I've been trying to think of a way of making op25 do tone 'detection' for phase 2. Seems like it should be simple since it's already got access to the AMBE+ codewords and known when it is receiving a tone frame vs a voice frame, but as usual the devil is in the timing details!