Even if you have no idea what you're doing, I very much recommend buying one of the RTL-SDR dongles on amazon for ~$20-30 and playing around. For the cost of a movie ticket, an afternoon messing with one will teach you a MASSIVE amount of stuff about how RF works.
Man, this seems like such a great resource; wish I had found it when I first got into SDR. I wrote a blog post about controlling ceiling fans using SDR (<a href="https://blog.hmac.io/2019/10/25/making-dumb-fans-smart-using-software-defined-radio.html" rel="nofollow">https://blog.hmac.io/2019/10/25/making-dumb-fans-smart-using...</a>), but I glossed over my initial struggles just getting up to speed with this stuff. All the concepts of SDR are straightforward and fairly intuitive, but it's the software stack and actually using the tools that's hard. The whole field is niche enough that you end up stubbing your toe with every step you take in that world.<p>Googling around and trying to figure out where to even begin comes up with so many fragmented, unhelpful pieces of information. You either end up being pointed at Gnu Radio, which amounts to an incomprehensible behemoth for a newbie, or you find the numerous lighter weight pieces of software which aren't very clear on what exactly they're good for and are often unmaintained.<p>Luckily my first project was rather simple; ceiling fan remotes don't exactly use the most advanced protocols. Once I found CubicSDR and fiddled around with it enough I was able to dump the radio signals to an audio file and just tease the rest out in Audacity. My blog post mostly covers the nightmare that was the TX side of things.
Plug for the “universal radio hacker” open source tool. It made it absolutely childs play to reverse engineer a wireless thermometer signal which i now feed into a dynamo db table and present as a graph via alexa. My kamado joe is at the bottom of the garden and when i’m smoking or bbq’ing i can bring up the meat and the grill temps on any screen in the house. Fantastic.
Rachel Kroll (wrote The Bozo Hour making fun of incompetent sysadmins and management) created a web portal for an SDR in C. I found her blog posts in the project very interesting.<p>> <a href="http://scanner.rachelbythebay.com/" rel="nofollow">http://scanner.rachelbythebay.com/</a>
This write up is a great introduction to what can be done and is nearly word for word what I have been through so far with SDR and amateur radio.<p>Another super interesting thing I have done with my RTL-SDR is track NOAA and Meteor weather satellites and decode the images in realtime as they fly by overhead
Thanks for posting, I didn't know about LuaRadio.<p>After playing with some examples I noticed the weird behaviour of the gnuplot windows that get focused and refreshed (including decorations) at every sample so that beside wasting cpu power for unneeded drawing, it takes away focus from the shell where the program was invoked, making impossible for example to press ctrl+c to stop the program. I was forced at every test to ctrl+alt+f1 to a full screen console to kill the process.<p>There's a nice Lua GUI project called TekUI which includes a basic graphing control that could be imported and extended to do the same without the need of an external dependency like gnuplot.<p><pre><code> http://tekui.neoscientists.org/screenshots.html (look at about half of the page)
http://tekui.neoscientists.org/releases/
</code></pre>
It's highly portable, a few years ago I managed to compile and use it on a A10 ARM processor board (Hackberry if memory serves).
Thanks what a good link to SDR, the link feels like a Christmas present. SDRPlay is a good SDR receiver a step up from RTL-SDR for exploring the radio spectrum. Plus to exploring software defined radios there is a good community built around ham that one can join.
I want to broadcast (unidirectional) UDP packets over the air on 2.4 GHz or 5 GHz at 3+ Mbit/s at maximum (legal) power. Is there a good way to do this with any current SDR hardware? Or is my best bet to ab(use) wifi cards for this purpose?
When I was messing around with ADS-B stuff for work I found this website to be very helpful with lots of ideas/links for projects:
<a href="https://www.rtl-sdr.com/" rel="nofollow">https://www.rtl-sdr.com/</a>
I have some other questions:<p>1. Can Usenet (and perhaps also Unusenet) be used with amateur radio?<p>2. Can received AM/FM broadcasts be used as a input for SoX?<p>3. Is time synchronization possible with software defined radio?<p>4. Can it be used with a RF cable (such as to connect to a VCR)?
One project I want to do with SDR is relay + amplify my car smart key so that I can open my car from 50 feet away (as opposed to needing to be right next to it)<p>Is this possible?