Lots of dismissive comments in here, which I don't understand. KV4P did an awesome project that he spent a lot of time and effort on, and then shares it with the community. I think he did a great job, and I am very tempted to build one myself. I've been doing HF only, but this makes me want to start exploring VHF.
how the turntables. Back in the 80s my grandfather (N4MDB RIP) had a ham radio in his car and used something called an "autopatch" which could dial phone numbers. He'd call my grandma and say we were going shopping or whatever. Everybody from the shack could listen in with their radios.
He tried to get me interested in ham radio but at the time I was exploring the internet and ham seemed... boring? Overly fussy with its technical license and morse code? He did give me a shortwave radio and explain how radio waves could bounce off the atmosphere (which seemed like science fiction honestly) and I got to listen to numbers stations.
For any one interested in doing this, getting your Technician (lowest level) is pretty easy. If you're already familiar with very basic circuits and electronics you could probably go in blind and have a >50% chance of passing (there are questions you'll need to memorize). Go through the practice exams, you'll see.
But here's the thing, you don't need any time to wait to take the General test (mid level), and there are a lot of benefits to General. (Here's the chart for frequency allocation[0]) You can take the test the same day and won't have to pay an extra fee. (I've seen a few do all 3 in the same session, but time is probably an issue) So even if you don't get the General, it is worth the shot. You'll definitely need to study for the General though.
Your license stays with you for 10 years, so it can just be nice to have in your back pocket (and with this kit, quite literally)
True. Honestly, if I was going to do this (I won't) I would probably just set aside a couple weeks to train a deep net to parse and generate morse code (a near-perfect example already exists: https://github.com/f4exb/morseangel) and in the process of debugging the model, will end up dealing with so many audiovisual examples I'll end up knowing morse without actually studying.
Yeah those "autopatch" devices were illegal - Ma Bell had rules against connecting any radio to the telephone system. Probably worried about long distance revenue.
The portable radios/cord free telephones back then were a bit of a legal gray-zone.
This is a wacky idea, but the "modern" thing to do would be to repurpose seldom used 2-meter repeaters and make them 5G gNBs in the 3300 to 3450 MHz ham band (which overlaps NR band 78). Then you could directly use your cell phone (with a different SIM card) as your ham radio.
Network gaming servers to the gNBs and every kid in the US will want a ham license.
I went down this rabbit hole for a while a few years ago. I think it's doable, but I don't have good answers to a few questions:
1. How do you get cell phones to automatically identify in a way that satisfies the part 97 rules?
2. How compatible are modern smartphones with the null encryption cypher?
3. With fewer and fewer physical sim slots, is it possible for an amateur to produce valid eSIMs? (And is it possible without internet access, such that you could onboard new users during an internet outage?)
As other commenters mentioned, you need a core network too, which means you probably also need an 802.11-based backend network like HamWAN or AREDN plus some servers.
1.- You get a "nice PLMN" for the network and assign phone numbers (and manage key material) only after Ham Identification. DMR Style (at least here in Spain)
2.- Most of them will refuse to join any Private SA network that does not use SUCI and encryption (in my experience). If you have a "nice" PLMN, they will connect. What a "nice" PLMN is varies between modems, the testing PLMN is a safe bet :)
3.- Also gone down this rabbit hole. eSIMs must be signed by a GSMA authorized key, and they are picky. Osmocom people have relationship with someone that signs profiles for them (for pay). The crypto is quite straight forward to do offline, eSIM profile distribution not so much. Key propagation from generator to core network and final client (ue) would also be a challenge. Another option is using the testing certificate, it should remain active in most modems for certain PLMNs. I have yet to test this, but work gets in the way
There is a variety of open software and COTS hardware that could fully power this network. The client side is the hardest part, especially if you want a phone.
PC modems on a Linux machine are more manageable (But expensive, let's wait a few iterations on RedCap maybe). And SIMs with ADM keys can be purchased from different sources
I would love to set up a real managed digital network for hams, with stuff like roaming and the like.
But I'd be more interested in technologies that are one to many rather than the one to one calls on mobile phones. Open public channels keeps the ham community connected.
Something like DMR Tier 3 or Tetra would be great.
You also need a 5G core to make that work. Also probably an IMS to actually provide some services on top of that. You also need to rip out all the encryption for the ham bands.
You could always somehow make the vibration motor a "movement feature", and call the phone a "remotely controlled vehicle"
;-)
Chatgpt- Yes, using the vibration motor to make small position changes on a remotely controlled vehicle would fall under the category of controlling the vehicle. If you encrypt the control signals that dictate when and how the vibration motor activates to achieve those position changes, it would be allowed under the FCC rules for encryption related to remote vehicle control.
Since these encrypted signals would only be used for the vehicle's movement or positioning, this approach aligns with the regulations permitting encryption for controlling remote vehicles. Just ensure that any non-control communications remain unencrypted to fully comply with ham radio rules.
I'm 99% confident that wouldn't fly and the definition of encryption is broad enough to cover even a "loophole" like this. I believe you'd have to demonstrate that you're actually "controlling" the phone rather than just performing communication and I'm not sure the communication with a vehicle actually is covered by the encryption cutout. My understanding is that it is so others cannot take control of the vehicle you're operating (which may leave you liable for whatever damage they cause with it, or at least makes that more ambiguous)
The real core is giant mess of servers but it's all software, no ternary vacuum tube device is involved. There are few OSS implementations and some even commercial ones that runs on single PC.
I think you misunderstand my point. My point was: If you have to replace everything why not leave the existing repeater up and add all the new hardware as well :) There is no need to take down the 2m unless the location is severely power or space constrained, which is not really the case for most of the high sites I've seen.
Replacing it only makes sense if you could reuse some hardware so you have to choose one or the other (or to invest in buying new). But in this case it will be 100% new so that discussion doesn't come up.
This is something I've thought about quite a few times, and I think it is a crazy idea but worth exploring. I'm way too naive here and have had almost no time to experiment due to other priorities.
But I think you could set up a global mesh network. I think what sucks is the encryption rules, but if there could be a big enough force that demonstrates it and its usage, those rules could get changed (there is already pressure to do so).
Now one thing though is there's some fuzziness about the definition of encryption with the FCC's definition[0]. Would this include routing protocols and/or compression? If they're open source protocols? If call sign is sent uncompressed and clear? This seems to be kosher considering other projects I've seen. So the messages might be able to be snooped on by anyone, but this would mostly be for fun and demonstration, like Ham is. But also, I think it would be pretty cool to have an open global communications platform. It would definitely also serve as a useful thing for natural disasters. (But we're not in the cold war anymore... we have encryption over the internet and that's even much more obscured. It would be nice to see encryption and a community driven global communication network)
The other thing I've been wondering is if anyone has tried satellite bouncing with the starlink sats? I'm sure they wouldn't be too happy about that, but hey, it is at least interesting to understand conceptually since you could really get a much larger view area and you don't need to travel all the way to the moon. But doing this you could potentially open up the network for coverage over oceans (at least more easily)
http://www.mobilinkd.com/ is probably the closest pre-existing thing that is similar. I don't think this was lack of imagination, modules like the DRA818V make building a fully integrated unit a lot easier these days
I had so much fun operating APRS through the space station with a car 2 meter radio and a moderate mast antenna in a terribly hilly spot but be able to see stations in the South Atlantic and Midwest states. Also the time I was on a 2 meter HT walking in the woods and heard the astronauts talking to hams. And the time the computer told me it was just about to be visible and went outdoors and the ISS was huge and bright, more an airliner than an asterism.
There are combination PoC (push-to-talk over cellular) + WiFi + VHF/UHF radios.
I think the problem as it relates to HAM radio as a hobby, is that if you have cell signal and cell phone, usually any other radio is less effective.
So while it is nice to use the interface/battery/CPU of a cell phone to drive a radio, it's superfluous if you have a cell signal. If you don't have a cell signal, usually having 5W for analog voice in an HT is much more important than having a special interface or digital modes.
I used to ask the same thing back when car stereos were all the rage --- I wondered why I couldn't get shortwave or SSB or Air/VHF reception and the answer lies in use-case. Yeah, you and I might eat up this super niche product, but the market on the whole would not.
Just look at what electric car makers are doing with AM radio. They're saying "screw RFI problems, we'll not filter those and just remove AM reception from the car radio because who needs that?" The answer is a larger slice of the population than would want other radio services.
Even Apple never enabled the FM receiver feature on their chips from Qualcomm. It's all about the time spend designing it, ensuring it doesn't cause issues with must-have features, is intuitive to access/use, _and_ aligns with buyer demands.
With ham radio making up less than 1% of most countries' populations, the need just isn't there. (Most folks you talk to are doing good just to even be aware of ham radio, let alone actually be a ham.)
Yes, but think about having a mobile that has native integration with APRS or can make voice/packet radio or even DMR. It would be perfect for hiking or adventures.
Even better with LORA.
forgive my ignorance here please, but I've read about APRS on and off for a few years and always wondered what I'd need to just transmit some data that would eventually make it's way to the internet. I recently suggested it to a Ornithologist friend doing back country research in South Afrika too.
But why are there no regularly recommended cheap hardware solutions that can do this (and or just hobbyist builds using an RPI). Seems like the demand would be there but perhaps I'm just not understand all thats involved.
Any insight you could provide would be appreciated.
APRS is actually pretty simple protocol. Data is encoded by modulating tones in a human's hearing spectrum, so if you tuned into the APRS frequency with any-purpose scanner (like most Baofengs), you would hear your childhood if you are old enough to remember 52k modems. The sound wave is easy to decode and encode with software. There are plenty of programs (Linux even has dedicated kernel modules) which turn your sound card into a modem, and the missing piece is the radio.
Now, there are different approaches. If your goal is to receive only, you can plug the headphone output of the cheapest Baofeng scanner into the microphone input of your PC, run the software, and you will start seeing messages soon. If you want to transmit, you do the opposite, but you must somehow automatically enable transmission on the radio when the program wants to transmit; there are different methods of doing so, depending on the radio. Basically, you can use anything what can receive and/or transmit audio on 2m bands. Such devices are cheap and easy to buy, so people probably don't bother with assembling a dedicated hardware. Just plug it to the computer.
It's even simpler if you have an HT with a Bluetooth KISS TNC. You just pair the radio to an Android device, and run APRSDroid and off you go. No cables or configuration of a PC needed.
The B-tech UV-PRO and VGC VR-N76 just got firmware updates that allow that. So now you can do it with a $180 radio instead of needing to buy a $900 Kenwood.
thanks for the detailed answer, so following your explanation if I wanted to transmit scientific data at regular intervals (for my friends field work) what sort of licensing / permission would I need?
Funnily enough someone posted down a few comments here almost exactly what I had complained about not existing ( http://www.mobilinkd.com/ ) at least if I understand that page correctly.
I wish they would get LTE/5G peer to peer working. It is defined in spec but barely anything supports it. Then could do any networking instead of limited to ham radio.
What's even more amazing, the local search and rescue helicopters have been outfitted with special 4G/5G base stations. So if they are flying a rescue mission in the mountain or other remote areas, and they come in range of your phone, not only does your phone suddenly have coverage, but they can see you connect, triangulate your position, and call/text you directly.
They exist but they are no-name brands. The phone is crappy, the radio is crappy, and the combo is a big brick. It would be awkward phone with antenna sticking out.
The question is why don't handheld radios have Bluetooth and USB-C data (some have USB-C power).
The common workaround for FM radio was to use the wired earphones plugged into the phone as an antenna. But FM radio is usually extremely, unbelievably strong (a lot of hams know that), so YMMV for other bands with much lower power signals.
The Ulefone Armor 26 is available with a built-in UHF/VHF transceiver, but the software isn't great.
The opposite trend is radically changing business radio - a lot of devices that look like VHF/UHF transceivers are just cellphones. There just aren't a lot of environments where VHF repeaters provide more reliable coverage than LTE & WiFi.
I recently dug up my old iPod Nano 5th gen (small square one) from 2010 and charged it up, and still works fine.
What I forgot, and it totally surprised me, is that it has FM radio! I selected some stations and it worked great. And that Nano was tiny, would be cool to have this feature back in current iPhones / Apple Watches. I know it’s not the same as having full tx/rx on the 2m/70cm bands, but still, even just just listening to normal radio on iPhone would be cool.
> And that Nano was tiny, would be cool to have this feature back in current iPhones / Apple Watches.
That iPod used its headphone cables as the radio antenna. There's no easy way around that for a SmartWatch, and most people wouldn't be happy to carry a USB-C antenna dongle around with them for their iPhone.
You can of course start doing black RF magic with more compact antenna designs, but that's much more complex and still has a much larger footprint on the board than the FM receiver in that iPod nano has.
Ohh right yeah, I remember once reading about the headphone-cable-is-antenna, clever!
I guess that’s why we don’t see it anymore in devices, as everyone is using more wireless headphones.
I remember that my HTC Desire Z Android phone, and possible also the iteration of a Nexus Android phone that I later owned, had FM Radio. It was relatively common back then, and I made use of it almost every day on my bike commute and such.
They used the (wired) earphones plugged into them as an FM antenna, worked well enough.
I recently found my old e-reader (Kindle Keyboard) from 2011 and the first thing I had to do was swap a new battery in, the old one would not hold a charge for too long.
I haven’t played with it long enough, need to check again.
I’m also happy and surprised that all my music files are there and that everything works. I haven’t touched it in probably 4+ years, and was under the impression that flash memory, especially older generation like 2010, can degrade / bitrot if it’s not powered every so often.
I know very little about antenna technology, but physics might play a role. 2m/70cm is pretty far away from the few-cm-wavelengths of somewhat modern cellphones (70cm a bit less so). For FM radio, the common workaround was to use the cable of plugged in wired earphones as antenna, but I don't know how well that would work for bands where the transmitters aren't as unbelievably strong as they are for FM radio.
And then there's of course the fact that almost nobody is asking for that, so the engineering and maintenance effort behind it would be insane in comparison.
If you can parlay it into an 1/8 wavelength, 25cm is probably not impossible to fit into some monstrously meandered beast that could fit in a phone's footprint. We've come a long way in terms of miniaturizing antennas, though I'm no expert.
But I think your second point hits the nail on the head - cell phones have enough antennas in them, and asking to add another one at such a low frequency is a great way to get your antenna and QA teams to look for a more sane employer, and to put your EMC compliance partner's kids through college :)
Anyone that has a real need for something like that is either using either very specialized (and expensive) hardware, or some peripheral solution like TFA. We already have general purpose, mass produced devices that benefit from huge scale, and there's no such scale in amateur radio.
I wish this was for sale assembled. I know probably about 50% about printing PCBs compared to what I’d need to know, don’t have a 3D printer, and I expect that the firmware and apps probably have at least one or two quirks to take into account. All together, this makes it a big difference in accessibility between being able to buy an assembled item and tinkering oneself. I know tinkering is fun for many people, but having a mobile ham is fun for many more.
P.S. Upon second glance, it looks like I’d need soldering skills, too. These things really add to the price. The price of components may be $35, but the cost of learning all these things (time) and mistakes along the way may be in the thousands if we take the hourly rate of a tech worker. Flawed comparison, I know, but you get the point.
It's...not that hard. Unless we're dealing with SMDs, soldering takes about a weekend to learn correctly. Most DIY kits involve through-hole components that you can master after you take a cheap iron to a couple dozen header pins or something equally banal. SMDs, on the other hand, take a bit more finesse, but can be achieved with a wee bit of time and patience.
I work in industrial controls and it blows my mind how many people in the field are terrified of soldering, even something as simple as tinning wires so the crimps fit a bit better, let alone the amount of "DIYers" I meet that don't even own an iron. Y'all are holding yourself back by not learning this easy-to-grasp skill.
It’s not necessarily about how hard it is, but what’s the ROI on learning a skill. If soldering was something I did at work or if I often repaired my own electronics, then it could even be worth learning it if it took a month of evenings. But as I’d not have many of the tools and schematics to do component level repair on today’s electronics and I almost never need to solder anything at my software engineering job, so this skill would be used maybe once or twice in a decade on a hobby project, it is mostly not worth investing even one weekend.
We can learn a lot of skills that are useless. Coming from a conservative family, I learned to play the violin and piano at a very young age instead of spending time with friends. These are skills I never have any use for and I’d rather just have some better memories from my childhood. Even if learning to play piano was relatively easy — with one weekly lesson over about 6 months it is extremely doable.
Those are sort of the real costs and benefits of learning skills. Easy or hard doesn’t mean necessarily that it’s worth or not worth learning.
Respectfully, you're over thinking it. In the time you took to write this post (what was the ROI on that?), you could have soldered your first thing. Unless you're really not interested, you should just do it.
Learning how to solder (and to solder very well) is much easier than learning to play the piano or the violin.
It's also tool-using skill that changes the way one thinks about stuff; it opens doors.
These days I'm fairly comfortable and confident with ordering custom PCBs to support various hardware and software projects. This lets me build stuff that I would not have imagined without the ability to solder.
I don't do component level repair at work or at home if it goes beyond changing out an obviously-bad electrolytic capacitor or something, but I have rescued many things quickly and inexpensively by swapping things like obviously-bad electrolytic caps. That saves me money, and by extension it also saves me time.
I wouldn't have ever considered any of that if I didn't know how to solder.
Bonuses: Unlike learning piano, it doesn't take six months to learn soldering. And unlike the piano itself, the soldering kit is inexpensive, portable, and low-maintenance.
Honestly, learning things and doing projects together brings memories too. If that wasn't the case, your family was doing it wrong.
Plenty of kids jam together in a garage, have awesome memories from the school band, or otherwise. Great memories are formed. Or sitting around a camp fire playing a harmonica or a guitar.
If you're learning "instead of" rather than "as a means to," well, there's your problem.
I think a relevant gap you may be underestimating is "if you finish your solder job and it just doesn't work, what now"?
Just getting some melted metal onto a thing is really ~none of the skill cap that makes it "scary", when it inevitably doesn't work, the skill involved in debugging it, fixing the issue (desoldering), identifying if you fried other small cheap components that may need to be replaced, that's really the part that makes soldering a scary skill.
FWIW I think this is an example of a broader class of "being a beginner is much harder than knowledgeable people think"; if you're skilled then you also actually don't make nearly as many basic mistakes to begin including the connection being bad, accidentally shorting, wrong polarity, wrong sized component, and you'll recognize something might be problematic right when it happens. That means you don't even need to do noideadog debugging when a beginner must.
You can probably imagine doing "carefully solder and just fail the project if it still doesn't work at the end" being a strategy that would have a pretty good success rate, when it would actually have a dismal project success rate for an actual beginner.
All of those knowledgeable people were beginners once, made those mistakes, and came out the other side as knowledgeable people. You'll never do anything if you don't start somewhere. This is a fairly simple electronics project, with relatively easy soldering.
I am not sure what gap you mean, since troubleshooting is part of the learning process. If someone expects to always get it right the first time, they are a bad student. Problem solving is relevant to all learning.
What I meant is that the comment said that you can learn soldering in a weekend and described only the physical aspect of getting solder onto some components.
I spent a number of weekends trying to get any intuition over basic circuitry components and how you might debug things and got basically nowhere. I can put some hot metal on stuff but it's not useful if you can't debug and the knowledge needed to debug isn't remotely obtainable in a weekend.
SMDs are not that bad, I always design my boards with SMD components, though I never put smaller than 0805. The chips are even easier to solder once they are fixed at two or three points. I totally abandoned THT elements once I felt confident with surface mounts. I'm doing this with an iron tip, so no BGAs for now (until I turn old toaster oven into a PCB oven).
> may be in the thousands if we take the hourly rate of a tech worker. Flawed comparison, I know, but you get the point.
I get what you're trying to say, but if "tech worker hourly rate" is your metric and "putz around with ham radio" is your goal, honestly, the answer is go buy an off-the-shelf radio for 1-3 TechWorkerHourlyBuckaroos [1]
If the goal however is "tinker with electronics", the relevant metrics are precisely "counting up the mistakes" and "tallying up the opportunity cost wasted at the workbench".
"Why buy this for x when I can build it for x^n" is the motto of any sufficiently-respectful building-shit hobby in the era of global drop-shipping.
[1]: +/- the "ham spectrum requires a test and a license before you can touch it" legaleese
Don’t get discouraged. This is a good opportunity to dabble in each of these areas and this is a project that the author shows will work, so you can follow the recipe. There’s some up-front investment for tools, but you may find it fun and challenging.
You have to get a ham radio license and a callsign to lawfully make bodily contact with a ham radio device. Reading through textbooks and taking tests on a sunday and shaking hands with cellular clones of Gabe Newell and all that.
Allegedly that's easier for some or unbearably gross for some in comparison with soldering.
As long as the end user assembles 51% of it, you don't need it. You self-attest that the device is in compliance. You also have to perform an "RF study" but there is no requirement for documentation on that.
Don't have my license yet, but for me it's definitely building homebrew (i.e. designed by me) transceivers. Not actually that interested in talking to other hams except for then testing my gear.
Heh, I'm not that interested in talking, but I am interested in typing. Especially with the advantage of advanced math/error correction, store and forward, relaying, and related. This adds up to a few watts in a $100 radio getting across a country.
Not sure if you mean building or designing and building. But QRP labs has some nice kits.
It's a ham project, you self-certify. Part 97 allows you to build your own equipment.
Now, in doing so, you're also taking responsibility for your emissions, and you're expected to be diligent about making sure everything is within the rules. But there's no paperwork or anything unless you want there to be. (Taking notes about your spectral purity testing is probably a good idea, you'll probably never need them, but if someone complains it'll be nice to have.)
If it were an emergency backup you have basically free reign, afaik all the FCC rule parts have an exception for emergency use. The tough part is you'd ideally want to test your backup before the emergency too.
The key selling point is the single power source. Most average consumers carry charging tools for their phone, and don't want to manage another device like a radio.
I personally prefer standalone handy-talkies, but powering them is still a pain. I wish a company would redesign the baofeng to run off of 18650 cells
The UV-9R Pro takes batteries that have a USB-C charging port on the back. I have a couple I setup as my disaster radios because of that and them being water proof(ish, better than other models at least). Programmed them with the local repeaters, weather channel, and the 2m and 70cm simplex calling frequencies plus whatever the default channel setup was.
i have a couple usb-c and though they are better than the previous baofeng, they still don't scale very well, and the battery cells now cost more and are less reliable.
I'd recommend something like a couple $25 Quansheng radios instead. More reliability, more range, less finicky, more durable and about the same size as this add-on.
(For some reason the radios are showing as $30 right now)
Yeah I have 4 that are great 2m/70cm, which is what the included antennas are optimized for. Even better with a cheap Nagoya antenna and non-stock firmware.
Unfortunately people don’t realize that even if you install a firmware that allows down to 11m, even connected to a $1200 base antenna the power output will be in the milliwatt range while throwing off on harmonics.
There’s also the case of hardware inconsistency and fakes. When I hook up 4 of the included antennas to my VNA there’s pretty big variance, and I recently tested a fake Nagoya that was clearly tuned for air band and not 70cm/2m as advertised.
The Qansheng's that I've tested have been fine, first harmonic down 44dB, which is OK for the FCC.
However, if you hack the firmware and transmit outside the bands the radio's RF is designed to transmit on, then you will probably see all sorts of spectral weirdness.
Another issue is people were “testing” them using an RTLSDR which very easily gets overloaded and shows harmonics where there are none. Even my local FM station shows up on my SDR at frequencies I know they’re not actually transmitting on.
I think it's poor practice for the seller to advertise those simply as a "Walkie Talkie," as that Amazon link does, without making it clear that it is an amateur radio transceiver that requires a license with an FCC-issued call sign to operate. I wonder how many people buy a pair of those and then just start transmitting without quite knowing what they are doing.
Using GMRS requires a $15 license that has no test and is good for 10 years. But nobody ever gets the license. GMRS is constantly full of chatter everywhere you go. Nobody ever mentions needing to get a license. You see YouTubers constantly using and promoting "Rugged Radios" which are just rebadged Baofengs. They are sold by the thousands.
Might want to consider the meshtastic, something like a lilygo t-echo. A few advantages over the standard ham radio:
* Nodes automatically forms a mesh
* works with any android/IOS widget, simple text message like interface
* store and forward means all nodes don't have to be online at the same time.
* Cheap, no soldering, and no ham license required.
* Can use phones GPS, makes it easy to track other nodes
* Don't have to program in repeaters, every node can repeat.
Meshtastic(Lora) also doesn't require a license since it's in the ISM bands.
Lora also has really good FEC and other things that make it work incredibly well(at the cost of throughput). Honestly I wish we saw more things like that in the ham bands(other than FT8).
There's a couple Lora radios out there that are USB serial based and can be controlled with AT commands that would let you so something similar if you want to build up from scratch.
This isn't true, it is not exclusive to the ISM bands. You can run it on any band you choose so long as you have a license to do so. Case in point: the ham bands
Sure, that's "technically" correct but most usage of Lora is going to be in ISM since that's where they are traditionally deployed. That doesn't require a license which can be a hurdle if you don't already have one.
I've got a ham license so not a big deal for me but for those wanting to try radios without a huge investment a pair of $20 Lora AT serial radios are a great way to dip into digital radio.
Note that various ham bands have limitations on what types of emissions are allowed. For example some only allow RTTY and data, so no phone or image. And some allow phone or image but no data. Even if the type of information is allowed there might be technical restrictions prohibiting some forms of modulation.
So before using something that was designed depending on some non-ham part of the regulations for its legality, such as part 18 (ISM) in the US, on a ham band I'd want to look into the details and make sure it is not doing something under that part but not allowed under the ham regulations.
Also, the ham bands as a whole cannot be used for profit-motives or any financial gain. People often forget this rule. Not to mention the (kind of absurd, IMO) rule against any form of encryption.
almost every single repeater I know of uses this method for remote control. I even remember listening to someone sending long strings of high speed DTMF, presumably to try and brute force control of the repeater. One of the managers said they weren't successful
In the US, there certainly is. The rule doesn't mention encryption specifically, it just prohibits "encoding for the purpose of obscuring meaning". The intent is what matters not the method.
Decent walkie-talkies are cheap. Cheap enough that I bought some for my kids to play with instead of a single channel garbage radio like I had as a kid. If you really want a cheap programmable radio Yaesu and BaoFeng are the brands most people go with.
> This would be amazing for backcountry communication
At 1W, you'd be better served with little FRS/GMRS radios. Better still, for less than the cost of building this yourself, you can buy ready-made a Baofeng UV-5R for under $20. The antenna is a little crummy, but you can buy that and _still_ be under the $30 build price. Further, the Baofeng isn't supporting a whole operating system so the battery will last much longer. I wouldn't want my "always-on" phone draining its battery until I need to transmit to someone. 1W is only going to be useful to hit repeaters in an urban environment - but because it's 2m (and not 70cm), it's even less likely to be all that useful beyond a neat/fun build.
I wonder how good the range would be. I was thinking that even if I didn't have the appropriate license, having something like this in a pocket on my backpack would at least give me one more signaling option in an emergency. I could deal with the fines later.
Generally speaking, line of sight. Assuming you're in the US, the FCC wouldn't come after you for using this in an emergency situation unless you were being absolutely egregious about stomping on other emergency comms, even then I seriously doubt you'd see a fine.
Having said that you're basically going to need enough knowledge to pass the test to make use of this anyway. Why not just take the test and be legal?
Yes. You can use a PO box, but since all past addresses and changes are visible in the database, you have to get the PO box _before_ you get your very first license, in order for it to be meaningful.
Well, for white pages, it used to be name to phone number lookup, not, you know, physical address, in almost all cases. Yellow pages were different ofc. And the tide against that turned 20 years ago, which congress banned that for cellphones.
In any case, sounds like "yes".
Not a deal breaker, but concerning. I know folks in my home would be opposed to my doing it.
Sometimes yes, not always, and practice decreased as privacy concerns increased. The old one for our city that was still printed up to about a decade ago did not have them.
And yeah, could probably find some way to spoof.
And yes, people can find things, just makes folks here uncomfortable that it would be readily available to a random nut in a short list linked to a "pseudo" one might be using routinely.
Anyway. It's one more hassle and disincentive. I'm interested in its potential for an emergency out in the woods (I'd be carrying my phone anyway, so a tiny pocket dongle is far less weight than a radio), but if I learn how to use it, I probably won't go for the license.
Agreed -- I'm with you 100% on the opsec hygiene regiment.
But FWIW, I think "Firstname Lastname Postal_Address" has never been easily kept private (indeed, the winning strategy is subterfuge), and that adding "Callsign" does not change that equation.
Of course it does mean that you shouldn't use your callsign as a pseudonym online. And I am not a person who is comfortable with the idea of a ham vanity plate! :) But with proper hygiene, your callsign is just an arbitrary alphanumeric string that is attached in exactly one place, to another instance of your name/address in the wild.
One thing getting a license would do, is give you an idea of how to maximize your tx/rx options. Understanding RF propagation in varied terrain could be valuable in an emergency situation.
If you already know this stuff, then the license exams are very easy.
Yeah. It's something that interests me and that I wouldn't mind learning, I just don't have an enormous motivation to get a license and the archaic (IMO) requirements on public listing are a part of that. I wish they'd rethink that policy.
But, I could just get some training just to improve utility in an emergency then take the license thing under consideration. I know some hams so wouldn't be too tough to learn the basics.
See https://www.n1fd.org/2019/03/23/tape-measure-yagi/ for a upgrade to a 2 meter HT that will make it into a repeater 100 miles away under ordinary conditions and could go 300 miles under extraordinary conditions.
You need to know the squelch keys for repeaters and get some practice, it never hurts to get to know the people who run the repeaters, check in on the nightly net, know who is listening. So it is worth getting the technician license, there is no Morse code, just a multiple choice test run by friendly hams.
One rainy night I was talking to an amateur storm chaser who was reporting on conditions close to the inlet and asking why the repeater wasn’t so busy during storms like back in the day there were lots of storm chasers and I told him that NOAA advises people not to drive into flooding prone regions so most of us don’t do that because we don’t want to become part of the emergency.
Other times in the rain the air is silent but you know there is at least one ham monitoring who will call 911.
VHF / 2m is basically line of sight. But it will go for long distances. I've worked the repeater on the ISS with a 5W handheld radio and a 1/4 wave antenna.
I'm not in the market and clicked the link out of curiosity, but yes, I can turn my android phone into a hair dryer if it takes $35 of auxilary equipement.
I'd love to see that actually... Most hair driers are very power hungry. 2kW is not uncommon (at least here where standard voltage is 240V). Achieving substantial amount of drying from a mobile phone battery would be quite a feat of engineering.
Make a small rechargable hair drier for camping/use where outlets are in short supply, and you've got yourself a saleable product, even it it only gives about 5 min of hot air.
If battery powered, it would be a very expensive device and require a big heavy battery.
Power tool batteries, eg a dewalt 18v drill, allow a max discharge current of around 10 amps. So for a 600 watt hair dryer, you're going to need 3 power tool batteries! Imagine the cost/weight of that!
To make it work without the high cost/weight, you're going to have to blow mostly cold air and hope the user is okay with that.
I agree that it is an interesting configuration, but I also agree that it is click bait.
The clickbait part is the "Turn your Android phone" bit. Of course you can turn your Android phone into <x>, where <x> is a USB-powered device, for approximately the price of <X>.
The build cost of this (about $35) is very cheap for a ham radio with the features that it has, so "approximately the price of <X>" is what i'm taking issue with here
Good BMS systems which don't stress the battery, limiting max SoC, liquid cooling, not using its peak current draw as often, etc.
Also most drivers won't really use that many charge cycles per day or whatever. I easily use like 90%+ of my phone's battery every day, I'll use up most of my laptop's battery when I'm on the go. Both of these devices often sit at a high state of charge and goose the voltages more to get more juice out of the pack at the expense of how many cycles they're good for. Meanwhile it's not like I'm driving >200mi every day.
By "managed", they mean periodically charged and discharged, and kept out of the heat. which is why I don't want to keep a baofeng battery in my glove bod
Such a thing is clearly possible - various debug and calibration modes for these modems make them output the raw I/Q values needed for a software defined radio.
Unfortunately, in a locked down production phone, those modes are unavailable.
In remote areas with group of people, I have an idea where all phones could linkup like those tesla cars in a mesh-network fashion and then all of them become a loudspeaker.
