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Ham radio is well worth getting into if you come from a software background but want to get more hands-on with embedded electronics. Radios are ubiquitous in mo
by tiniuclx 11mo ago
Ham radio is well worth getting into if you come from a software background but want to get more hands-on with embedded electronics. Radios are ubiquitous in modern technology, and getting a deeper understanding of how they work can have surprising career benefits too!
- ACCount37 11mo agoThe RF fundamentals stay the same, but the gulf between ham radio and modern RF comms is truly vast. Those TDM'd bands 40MHz wide, with digital data and modulation past the limits of sanity, and the entire RF system being integrated into one die somehow? Oh boy.
- jacquesm 11mo agoWhat really blows me away is the range that you can achieve with almost no power on tiny little antennas. For instance, ELRS uses a transmitter/receiver that is less than a gram, that can keep a link with a drone alive across 30 km or even more. And the antenna is so small you might toss it away with the packaging if you're not paying attention. One example: https://rcmaniak.pl/userdata/public/assets/images/SpeedyBee/ELRS-2G4-RX/SpeedyBee%20Nano%202.4G%20ExpressLRS%20ELRS%20Receiver1.jpg https://rcmaniak.pl/userdata/public/assets/images/SpeedyBee/... Oh, and it also speaks WiFi, just in case and it has its own little onboard computer and a web server.
- tappaseater 11mo agoI used to follow the balloon projects that hams would launch. A mylar balloon with a tiny 50 milliwatt transmitter and GPS, solar powered on the 10Mhz band tracked thousands of miles away.
- mystraline 11mo agoYep, its called LoRa. Ive been able to decode as low as -26 SNR. Theres LoRa chips for 2.4GHz, 900MHz, 868MHz, 433MHz, and 144MHz.
- stavros 11mo agoI use this one, with an onboard antenna: https://imgaz.staticbg.com/thumb/large/oaupload/banggood/images/EB/58/fe086da4-4b42-49c1-b1b1-f25f107a2621.jpg https://imgaz.staticbg.com/thumb/large/oaupload/banggood/ima... It's a centimeter on a side, and easily goes more than 10km. It's just mind-blowing that this exists. 0.9 grams, IIRC.
- jacquesm 11mo agoWow, that's an even better example. I already have a hard time finding the radio sometimes, and need to put on my glasses, with that one you need tweezers to mount it :) I ran into your tuning tips page the other day by way of a random search!
- stavros 11mo agoOh nice, I was hoping they'd be useful to someone! With that radio, I just use a drop of hot glue on the fuselage, and it works great! Plus, it's easy to find then :P
- jacquesm 11mo agoI'm having a devilish time tuning a drone using Inav, I've read through a mountain of documentation and tried a whole pile of things but so far it has not led to a breakthrough, just gradually increasing insight. Oh well, better to keep plugging away at it :)
- stavros 11mo agoLet me know if you need help, I've done it a few times.
- jwr 11mo ago> the gulf between ham radio and modern RF comms is truly vast Especially if you consider modern cellular radios. Your phone has a completely separate powerful computer just for handling the radio (we still call this a modem for some reason), with a large software stack running. As for modulation, starting with LTE and turbo coding, we are now near the maximum theoretical channel capacity (Shannon limit), which is mind-blowing. Learning the basics of radio is still worth the effort (and great fun!), but the gap is indeed huge.
- ACCount37 11mo agoI did some LTE work. Nasty stuff. And 5G is even worse.
- vetrom 11mo agoI don't think most people really understand the compute complexity required for LTE and 5G terminals. It's telling that pretty much every discrete-ish full-speed LTE or 5G modem I've lain eyes upon is actually an embedded SBC running its own OS, with attendant power requirements.
- ACCount37 11mo agoThe companies do that because by far the largest market for LTE/5G modems is smartphones. They could make a more cut-down modem chip, but why would they? They already make hundreds of millions on smartphone SoCs. Just rebadge that silicon as modem ICs, no one cares that an LTE stick runs full Android.
- willis936 11mo agoWhen I flip through the ham radio outlet catalog and see what people pay for a bog standard class A amplifier I realize how I am in the wrong line of work. The coolest modern ham stuff is happening on SDRs like hackRF.
- mschuster91 11mo ago> Radios are ubiquitous in modern technology, and getting a deeper understanding of how they work can have surprising career benefits too! Indeed. The problem with many modern ham radios of any sufficiently complex feature set - especially when it comes to cheap hackable radios or digital radios - is that a lot of the functionality is hidden away in blackbox ASIC hardware blocks that have no public datasheets (e.g. BK4819 powering Quansheng's radios, Si4732, or for anything DMR, the AMBE-2020 vocoder). It's truly a miracle what the hacker community has gotten out particularly out of the Quansheng chipset.
- subscribed 11mo agoGet the appropriate licence and build your own :) Either from the kit or from scratch :)
- mschuster91 11mo agoIt's not that easy. AMBE is patent encumbered and SDRs are black magic on their own.