I’ve continued processing the data generated from software-defined-radio recordings I made during the 2017 solar eclipse at my fairly isolated and low-RF-noise location on Beaver Island, Michigan (45 38 38 N, 85 29 24 W, grid square EN75gp). The nearest AM station is about 28 miles away, so it’s a
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SDR
I set up a smaller version of my mad-scientist stuff at our cottage on Beaver Island, Michigan (45 38 38 N, 85 29 24 W, grid square EN75gp), to record the RF spectrum before, during, and after the eclipse on August 21, 2017. The recordings were successful, and I captured
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It wasn’t too hard for the HamSci guys to convince me to bring a Cesium frequency standard to my portable location in Michigan to drive the HPSDR receiver that will do band recordings for the 2017 Total Solar Eclipse HF Wideband Recording Experiment. I had been planning to use
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I was fussing about signal generator output accuracy because I wanted to calibrate my
HPSDR Hermes software defined radio (“SDR”) so that I could calculate the absolute power input in dBm, assuming a 50 ohm load impedance) based on the dBFS (db full scale of the ADC chip) output from
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With op25 successfully decoding the control channel, now you just need to set up the trunking configuration. To do this, you’ll probably need to set up three files:
1. trunk.tsv
defines the sites to be monitored.
2. site_name.tsv
provides a table of talkgroup numbers and names for that site.
3.
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The info in this and in part 4 was aided tremendously by several folks on the “op25-dev” mailing list. Without their help, I would not have even known where to start in getting my system running. I hope that what I’m documenting here will be helpful for others going down
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Here’s how to install the OP25 scanning software. If you don’t already have Gnuradio installed on a Linux system, do those two things first.
Any current Linux distribution works. I use Linux Mint which is very similar to Ubuntu.
The easiest way to install Gnuradio is to use a script
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A couple of weeks ago at the Dayton Hamvention I bought a fancy Whistler TRX2 scanner that can receive the new P25 digital trunking system that’s been rolled-out statewide here in Ohio. Unfortunately, after a lot of attempts, I still can’t get it to reliably receive the talkgroups I’m most
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