[HN Gopher] Handheld two-way radios for preppers and other curio... ___________________________________________________________________ Handheld two-way radios for preppers and other curious folks Author : wglb Score : 59 points Date : 2021-02-18 16:47 UTC (2 days ago) (HTM) web link (lcamtuf.coredump.cx) (TXT) w3m dump (lcamtuf.coredump.cx) | swiley wrote: | Where I used to live no one plowed the road so every time it | snowed my dad to drive his bobcat (he's one of those tech workers | that owns machinery "for fun") down an hilly icy road with huge | ravines on each side and no cell signal. After we both got our | HAM license he would carry one of these cheap 2m handhelds with | him and could check in with us every so many minutes. They work | _way_ better than FRS radios (much more power, longer antennas, | more bandwidth (FRS is almost unintelligible by comparison.)) | | Some people feel like HAM has no practical use outside of | emergencies but there are definitely places where the owners of | the spectrum have failed to build the infrastructure needed to | use it. | rsync wrote: | "Some people feel like HAM has no practical use outside of | emergencies but there are definitely places where the owners of | the spectrum have failed to build the infrastructure needed to | use it." | | I keep reading about all of these very interesting protocols | for texting over HAM radio ... and a lot of them seem very | promising. | | My next step is to survey the landscape of devices that could | be used to actually send and receive these text messages ... | and there are none. | | Am I mistaken ? Does there exist a handheld radio that can be | used to send and receive text messages over one of these HAM | protocols ? | swiley wrote: | lots of people are using a PC or phone running the software | and either connecting that to a radio via the line-out port | or using an SDR. | sobriquet9 wrote: | DMR radios support SMS. But without a keyboard or touch | screen it's not particularly user friendly. And you can't use | encryption. | 177tcca wrote: | Are we done caring about the restriction on encryption? I'm | down. | throwaway3neu94 wrote: | No, we aren't and we like it the way it is. | | The last thing ham radio needs is corporations just | _taking_ our bands, or ham radio getting banned in unstable | countries over espionage concerns. | | If you want encryption, use a cellphone, LoRaWAN etc. | 177tcca wrote: | But...there's tons of projects already in use which use | protocols that, if the regulatory body isn't following | every open source project & actively updating their | intake tools, effectively act as encryption schema. | throwaway3neu94 wrote: | Could you give me an example or two so I can better | understand what you mean? | | You're not entirely wrong, an undocumented plaintext | protocol is functionally not much different from | encryption. | | However, those which are legitimate (ie, just | undocumented, not intentionally encrypted/obfuscated) | don't tend to cause problems as only one or few ham devs | would be using them. They can only get widespread | adoption by other hams if they are documented. So this | regulates itself. | | A corporation, on the other hand, is not like some ham | dev coming up with their own protocol. They can design | their own protocol, and then roll it out on thousands (or | much more) of transmitters. So just one corporation can | cause quite a big problem, with zero public | documentation. | | The laws as they are, together with direction finding | skills, are the communities only (legal) tool to defend | against that. | | That does not mean hams don't see the value in | encryption. I do! But it's a trade-off, and I think this | is the only way it can work. The legal change I would | like to see is explicitly allowing cryptographic | signatures. Right now it's a grey area (likely legal, but | not court tested) | 177tcca wrote: | Great points, especially, | | > They can only get widespread adoption by other hams if | they are documented. | | > So this regulates itself | | Until the first project gets traction that allows you to | easily drop in public/private key encryption of payload. | myself248 wrote: | Seriously! I keep feeling the same lack. I want something in | the form factor of an early Blackberry or something. | | I'd love it to have three radio decks: One ham transceiver, | so I can use direct APRS-or-whatever with other nearby nodes | or digipeaters, though I know the antenna will suck. One | Bluetooth, so it can act as the QWERTY UI for a more powerful | radio that lacks a decent keyboard (or as a generic | peripheral for other projects). And one Part-15, perhaps LoRa | or something, so it can also operate in an unlicensed mode | with Meshtastic or something as the protocol over longer | range than Bluetooth. | | I'm pretty sure I could design the hardware, both the | electronics and the enclosure, but I can't code my way out of | a wet paper bag, so that's sort of a non-starter. | | The bigger question question is, why doesn't this exist yet? | Are there HTs with native Bluetooth so the texting UI could | be implemented as a phone app? I know there are some with | Bluetooth for other functions but I'm not clear on whether | they can act as a KISS TNC over SPP. | | If so, that would be a great interface to standardize on, | implement the phone app for testing, then turn it into a | physical gizmo to enjoy longer battery life and | cheaper/rugged hardware. Then as a next step, bring the | Part-97 hardware into the gizmo. | throwawayboise wrote: | Morse code? | brians wrote: | Sure, a Kenwood TH-D74A can send messages over APRS. The | older '72' could too. So can a Yaesu FT-1DR. Plenty of | cheaper devices can too. Now if you look at those, you'll | find some odd ideas--features like a built in 320x240 camera. | They're an odd mix of very young and very old tech ideas, | because they're the products of small engineering teams and | weird budgets. | throwaway3neu94 wrote: | I would not recommend analog APRS for _reliable_ text | communication, or anything except periodic, unidirectional | (radio to internet), fire and forget position /status/etc | reports (for which APRS often can't be beat due its to | extensive coverage in many regions). | | Instead, try DMR. Does voice, text and also digital APRS. | Motorola and Hytera are probably the leading manufacturers | of radios. Works direct and via DMR repeaters. If you have | a repeater close by, you get worldwide radio to radio / | talkgroup calling. | | Unfortunately both modes have many, many annoying | quirks/constraints. | rsync wrote: | "Instead, try DMR. Does voice, text and also digital | APRS." | | OK, but how do I physically key in the text message from | the handheld device ? Is it the old-fashioned pre-qwerty | method of pressing a number once or twice or thrice to | get the desired alpha character ? | | Perhaps my initial question was not clear: In the most | primitive of ways, _how do I actually key in a text | message on the handheld device_ ? | throwaway3neu94 wrote: | Oh. Yes, those DMR radios have T9 keypads. Its awful, but | the best we have. | | For analog APRS, which as I said has questionable | reliability (for many reasons), you can use a smartphone | app (like APRSDroid) and either an audio cable to the | radio (the smartphone acts as a software TNC that will | generate the signal, the radio modulates it on the | carrier), or a separate hardware TNC which connects to | the radio via audio, but to your phone in another way | such as bluetooth low energy (like Mobilinkd TNC3). Then | you can type on your phone. (In that case, the protocol | is still done by the phone, the TNC only generates the | signal, the radio modulates it. Which is annoying due to | power consumption.) (Analog APRS support which is built | in to radios is usually position report only, not | messaging.) | NovemberWhiskey wrote: | Sadly, all those Kenwoods are now discontinued. | sobriquet9 wrote: | AnyTone, TYT, Radioddity, Baofeng and other cheap Chinese | radios ate Kenwood's lunch. For example, AnyTone D878UV | has built-in GPS and can send APRS messages. | wl wrote: | The AKM factory fire is a more likely the cause for the | D74's discontinuation than competition. | jasonwatkinspdx wrote: | HAM is still a very necessary tool for keeping in contact in | the mountains and such. When I was younger I did some SCCA | rally events. Those events would be impossible without the | volunteer HAM operators that show up and set up temporary | relays on a couple of the biggest foothills in the race area. | Cell coverage is just too spotty, and satcom stuff is just too | expensive. My understanding is that search and rescue uses the | same approach for the same reasons. | thangalin wrote: | > HAM is still a very necessary tool for keeping in contact | in the mountains and such. | | Depends on the location. The company I work for produces a | mountain-top repeater[0] series. Hundreds of them are | distributed throughout the Rocky Mountains in British | Columbia, providing an expansive coverage for handheld | devices. | | If you're curious about what an installation site looks like | atop a mountain, check out pages 38-39 in an older product | guide[1]. | | [0]: https://codancomms.com/products/mt-4e-series | | [1]: https://www.yumpu.com/en/document/read/38724760/land- | mobile-... | [deleted] | imwillofficial wrote: | This is cool! Thanks for sharing! | rsync wrote: | Would somebody please, please produce a very high quality, | rugged, handheld radio case that can hold a raspberry pi zero and | an RTL-SDR ? | | So, not a computer, not a smartphone - a plain old motorola-esque | handheld radio with physical buttons and a simple screen - but | underneath, it's an extensible SDR platform. | | Why doesn't this exist ? | invokestatic wrote: | I'd love a device like this, but I don't think a raspi zero has | enough processing power. My raspi 4 has a very hard time | decoding P25 as it is, and that's with active cooling. Probably | the best solution would be to offload the decoding to an FPGA, | but that kind of blows up the whole "software defined" part. | swirepe wrote: | Have you tried a hackrf portapack? It's an order of magnitude | more expensive than a pi zero and an rtl-sdr, but it might be | close to what you want. | Mediterraneo10 wrote: | Rugged cases are extremely expensive and become affordable only | through economics of scale that exceed an enthusiast project. | You could pay for custom plastic molding and waterproofing if | you wanted to, but the price would shock you. Look at how even | projects as relatively large and established as Pine64 products | are unable to get quality cases without becoming too expensive | for what its community is willing to pay. | ampdepolymerase wrote: | You can always design one yourself. Analogue Devices offers | many chips that are SDRs-on-a-wafer. The AD9361 is a | particularly popular chip. | rsync wrote: | No, the innards already exist - a raspberry pi zero and a | rtl-sdr. | | I am suggesting a nicely made, high quality, plastic case - | with buttons and screen - that has slots and mounting screws | inside to insert a raspi zero and a USB dongle inside. | | I quite like the standard handheld radio form factor - like | this: | | https://www.motorolasolutions.com/en_us/products/two-way- | rad... | | ... I just want a linux computer and an RTL-SDR inside ... | ampdepolymerase wrote: | Oh sorry, I misread. | imwillofficial wrote: | What people are trying to convey to you is your innate | choices are very poor and recommending better picks. Not | just for you, but for other readers who may try to follow | in your (poorly thought out) steps. | NovemberWhiskey wrote: | But that's not really a handheld radio; it's a scanner. An RTL- | SDR doesn't transmit. | chrisseaton wrote: | Case design and manufacturing is probably far more expensive | than you think. Quality cases even more so. Rugged cases would | probably astound you. | underseacables wrote: | Interesting, but complicated. It would be easier to just get your | amateur radio license and build out from there. Granted you're | getting a license from the FCC to operate, which might upset | certain preppers, but in terms of cost and availability of | equipment, the amateur radio route is much more direct and cost- | effective. | throwawaysea wrote: | Isn't a handheld radio an "amateur" radio? Or is there a | nuanced distinction between the two? | | It also does seem odd that this requires licensing. Why is | that? And if you were not licensed how would they even identify | you or track you down? | chrisseaton wrote: | 'Amateur' in this context means 'requires a licence to | operate but at lower tier of licence'. So no most handheld | radios aren't 'amateur'. | Mister_X wrote: | Q: "And if you were not licensed how would they even identify | you or track you down?" | | A: Ham radio uses a frequency band plan that everyone agrees | to adhere to, so if someone shows up on those frequencies who | doesn't belong, we will notice. | | Hams are also required to broadcast their FCC allocated "call | sign" about every 10 minutes, or when starting and ending a | transmission, if you're not doing that, then licensed Hams | will notice. | | If you think you're being "clever" and make up a fake call- | sign, we will notice, we know who the regulars on the Ham | frequencies are in our geographic areas. | | If you're producing "harmful interference", i.e. illegally | broadcasting on a licensed Amateur Radio Band, then some of | "us" Hams will get together and Track your signal, via | triangulation, and eventually we Will find your transmitting | location. | | Then we notify the FCC, and eventually... they will contact | you, and you Will stop, or face legal consequences. | | A lot of Hams enjoy tracking down hidden transmitters, we | even set up "games" to practice doing just that, we call it a | "Hare & Hound" practice. | | I'm quite good at tracking down harmful interference on the | VHF Ham bands. | | Ham radio has a lot of places to explore, but do avoid the | H/F bands, it's full of "rag chewers", and you'll want to | poke out your eardrums if you listen to them. | | 73, KE6--- | underseacables wrote: | Oh, a 2x3. Did you get into Amateur Radio late? | sokoloff wrote: | Answer 9 gives some info on which radios require a license to | operate. | | Direction finding/fox hunting is a way to get caught. In | reality, if you're not causing trouble, you're never going to | get looked for, of course. | wiml wrote: | "Amateur radio" or "ham radio" is a class of _noncommercial | radio licensees_ in the US and many other countries. There | are reserved radio bands, various rights and obligations, and | perhaps most importantly a large community of people using | similar technology. Think of it as the open-source version of | CB radio. | | The radio might be handheld or vehicle-mounted or a fixed | installation occupying hundreds of feet on a side. | (Conversely just because something is handheld doesn't make | it amateur: your cell phone is a commercial radio service; | walkie-talkies and FRS and wifi are unlicensed services; etc. | Type-approval is different from licensing.) | maxerickson wrote: | What in the link are you responding to? | Mister_X wrote: | I live in a remote area where Ham radio is still a vital | communication protocol during power outages and such, but lately | groups of non Hams (preppers, and such) have decided that buying | those cheap FRS radios will serve them during an emergency. | | And some of those groups are pushing people to get their FCC Ham | license and use VHF radios because they can be used over greater | distances. | | Unfortunately, almost none of those folks are actually practicing | with their radios to become comfortable using them. | | So when an emergency occurs, they have no idea of what to do on | the air, and they will cause harmful interference because they | are willfully ignorant of the local communication protocols | already set up by generations of Ham operators. | | They will be a part of the problem, not a part of the solution. | | I put on a "Jump Bag" presentation every year in my small town, | and I warn folks that if they get an FRS radio or Ham radio, that | they need to practice with it and become comfortable using it, | otherwise they will not be helpful during an emergency, and will | cause problems with the coordinated Hams. | | Aside from that, I also recommend against getting an FRS radio | unless they are willing to make sure the batteries in them are | replaced on a regular basis, otherwise when the emergency occurs, | they will find a dead FRS radio with corroded battery contacts, | basically a paperweight and nothing more. | | 73, KE6--- | 99_00 wrote: | Are they lacking technical skills or social/tribal knowledge or | both? | ryanmarsh wrote: | I know the Baofeng UV5R's are cheap but hear me out. I've gotten | some great use out of mine. Lots of preppers have these. Because | they're so ubiquitous parts and know-how are easy to come by. | | If you want to buy radio that you're never going to use, or | probably won't take the time to learn, get the Baofeng and save | your money. Don't wait for "perfect". Good enough is better than | nothing when the SHTF. | rreichel03 wrote: | This is an area I've been interested in learning more about for a | while (not for prepping, just learning). Are there any good | resources for getting started with ham radio? I've been looking | for a guide that can explain the math and physics behind it along | with the electronics. | cweagans wrote: | http://www.arrl.org/shop/Ham-Radio-License-Manual/ | | This is really all you need to get started. I was 14 when I | first got my license - I used an earlier iteration of this book | to self study. It's really straightforward. Feel free to email | with any questions! Always glad to help people get started in | ham radio. | curiousfab wrote: | I will additionally suggest the "ARRL Handbook" (there's a | new edition every year - mine was 2001 and I guess there is | no need to get the latest one), from which I learned | everything about electronics, antennas and radio propagation | during my high school years. It not only enabled me to build | and experiment with ham radio transceivers, but also gave me | quite a head start into my university studies of EE. | cweagans wrote: | ARRL Handbook is great, but I would suggest picking it up | _after_ someone has their license. Personally, I found it | really frustrating to have a gigantic book full of | interesting things that I wasn't legally allowed to do - it | was a much better book after I had my license :) | justin66 wrote: | The ARRL publishes books that would be of interest. | | > I've been looking for a guide that can explain the math and | physics behind it along with the electronics. | | Interesting. I expect that if the physics in one of their books | about, for example, antennas is not oriented towards math and | physics enough for your liking, you'll at least get some | direction as to what part of a real physics textbook you need | to study. | bretuls wrote: | Is there any commercial radio for private use with proper | encryption? | | It seems the only ones you can find are limited to 48 bit key or | so. | GekkePrutser wrote: | There's not much market for them, that's the issue. | | You can't use much transmit power on a free license. And hams | are not allowed to use encryption as a licensing condition. The | idea behind this is that you're a community. It's not really | meant for private communication. | | Some business radios offer excellent encryption but can only be | used with an expensive commercial license. | | The Family radio service ones are more for like walky talky use | on the go where encryption isn't so important, and they have | more limited range. | userbinator wrote: | _And hams are not allowed to use encryption as a licensing | condition._ | | But are they allowed to use steganography...? Same | difference, really. ___________________________________________________________________ (page generated 2021-02-20 23:00 UTC)