Hi all,
I'm very new to HAM radio and still in the process of reading my technician book prior to testing. In the meantime, I'm playing around with monitoring to get my feet wet and help prepare myself for the test with some practical knowledge.
A few years back, I attended DefCon and purchased a BladeRF X40 and XB-200 transverter from the Nuand booth because I was inspired by the conference as to the possibilities of digital RF. I played with it briefly but never got very far with it and it ended up collecting dust for a few years until very recently when I came across it and decided I wanted to get back into it.
So far, I've successfully demodulated/decoded NFM, WFM, BFM, and a little bit of DMR. I've primarily been using a combination of SDR Console (couldn't get SDR# to work) and GNU Radio Companion up to now and in the last couple of days have added VAC, DSD+, DMRDecode, DSD-FME, and Unitrunker (which I still have no idea how to use) to my toolbox.
I've gotten DSD+ and DSD-FME to decode DMR for me using VAC with minimal errors. Unfortunately, there's next to no DMR traffic in my area (Sherwood, OR). There are a couple of DMR repeaters in the area but they don't appear to be particularly active. However, I have been finding other digital signals between 800MHz-1GHz, some of which appear to be P25. Both DSD+ and DSD-FME recognize this data and appear to be decoding it, however I hear no audio. I've attached screenshots of my setup and DSD+/DSD-FME reacting to the signal.
Settings:
Mode: WFM
Filter: 12kHz/24kHz (tried lots of manual ranges to get tight on the signal but doesn't seem to have any effect)
AGC: Off (can't turn it on)
CW Peak Enable: Off
Noise Blanker: Off
Noise Reduction: Off
Notch: Off
Squelch: Off
Signal strength is coming in at about -10dBm so it's more than strong enough even with a meager indoor antenna. I've double and triple checked my audio settings in Windows and in the initialization message of DSD+. Not sure how to double check the audio settings in DSD-FME other than to wait for some DMR signal to show up and confirm it's audible.
While I have seen ENC frames (which I assume to mean encryption) on some channels, I do not see them on certain others which are the ones I'm focusing on.
Any advice, guidance, support, etc. would be greatly appreciated. This obstacle is really irritating me as this seems to be the only region with much digital activity in my area. I'd really like to be able to monitor it and, when I'm able, perhaps even participate in the traffic assuming it's open to public ham use.
Thanks for reading!
Ed
I'm very new to HAM radio and still in the process of reading my technician book prior to testing. In the meantime, I'm playing around with monitoring to get my feet wet and help prepare myself for the test with some practical knowledge.
A few years back, I attended DefCon and purchased a BladeRF X40 and XB-200 transverter from the Nuand booth because I was inspired by the conference as to the possibilities of digital RF. I played with it briefly but never got very far with it and it ended up collecting dust for a few years until very recently when I came across it and decided I wanted to get back into it.
So far, I've successfully demodulated/decoded NFM, WFM, BFM, and a little bit of DMR. I've primarily been using a combination of SDR Console (couldn't get SDR# to work) and GNU Radio Companion up to now and in the last couple of days have added VAC, DSD+, DMRDecode, DSD-FME, and Unitrunker (which I still have no idea how to use) to my toolbox.
I've gotten DSD+ and DSD-FME to decode DMR for me using VAC with minimal errors. Unfortunately, there's next to no DMR traffic in my area (Sherwood, OR). There are a couple of DMR repeaters in the area but they don't appear to be particularly active. However, I have been finding other digital signals between 800MHz-1GHz, some of which appear to be P25. Both DSD+ and DSD-FME recognize this data and appear to be decoding it, however I hear no audio. I've attached screenshots of my setup and DSD+/DSD-FME reacting to the signal.
Settings:
Mode: WFM
Filter: 12kHz/24kHz (tried lots of manual ranges to get tight on the signal but doesn't seem to have any effect)
AGC: Off (can't turn it on)
CW Peak Enable: Off
Noise Blanker: Off
Noise Reduction: Off
Notch: Off
Squelch: Off
Signal strength is coming in at about -10dBm so it's more than strong enough even with a meager indoor antenna. I've double and triple checked my audio settings in Windows and in the initialization message of DSD+. Not sure how to double check the audio settings in DSD-FME other than to wait for some DMR signal to show up and confirm it's audible.
While I have seen ENC frames (which I assume to mean encryption) on some channels, I do not see them on certain others which are the ones I'm focusing on.
Any advice, guidance, support, etc. would be greatly appreciated. This obstacle is really irritating me as this seems to be the only region with much digital activity in my area. I'd really like to be able to monitor it and, when I'm able, perhaps even participate in the traffic assuming it's open to public ham use.
Thanks for reading!
Ed
