[HN Gopher] Handheld two-way radios for preppers and other curio...
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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.
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