Listening to 700 MHz Simulcast public safety radio cheaply | Hacker News Reader

Listening to 700 MHz Simulcast public safety radio cheaply

kb9mwr.blogspot.com

77 pointswolframio7 comments

This sort of setup can also be used to monitor aircraft squelches. I got a few Raspberry Pis during a B1G1 sale, so I have one of these setups at work and at home. I like watching the planes as they take off from the local airport and queue up for arrival, and also seeing the nightly freight flights.

More info here: http://flightaware.com/adsb/piaware/

You can feed into sites like Flightaware and FlightRadar24 and get accounts with them that normally cost a lot for free.

Yes! I've been feeding into FlightRadar24 for some time to sate my strange curiosity with aviation. It's also Swedish company that is pretty accessible if you have questions or suggestions (and incidentally is hiring). I don't work there, just a big fan.

If people are interested in listening to signals I'd recommend checking out the ELF to VLF bands. You can, in most cases, build a receiver that operates directly on your system's sound card. These lower frequencies largely present an antenna building challenge but there's lots of interesting things down at those frequencies. Submarines, hams, and space weather.

The HF to EHF bands are fun but the lower frequencies, which are mostly ignored, are just as much of a gold mine for fun projects.

If you do not have one, get yourself an RTL-SDR today. This is a cheap ($10) way into radio and you will be impressed with what you can do.

From radio scanning to public safety radio to airplane tracking all with free software!

Agreed. While I love the analog scales on old radios and the glowing light behind the dials, SDR is so fun, portable and cheap to play with. After wetting the toes with repurposed cheap TV dongles, I'd suggest to get a dongle from rtl-sdr.com (satisfied customer, no affiliation whasoever). I have two of their dongles and while they're priced almost in the same league of the TV ones ($20 dongle alone, or $25 with 2 antennas) the performance wrt sensitivity and noise floor is remarkably better. Next purchase then will be a upconverter to get the interesting stuff aired in the HF bands. There are ways to convert dongles into direct sampling receivers for these bands; I can't report on their workings as I never tried them but without any filtering on the input I believe the performance won't be that good, at least compared to a full blown converter with filtering at the front end stage.

I use Dump 1090 on my Pi to catch ADSB signals, but I've yet to figure out radio with my sdr.

https://github.com/antirez/dump1090

Ok, I ordered one of these based on your comment. Looking forward with a new toy to play with when it arrives.

Reply on news.ycombinator.com