Turn your Android phone into a modern ham radio transceiver
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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.
Might wanna be careful, you might get your turns tabled and become that grandfather one day. :V
The portable radios/cord free telephones back then were a bit of a legal gray-zone.
> Yeah those "autopatch" devices were illegal[.]
Hadn’t the Carterfone decision[1] made them legal already in 1968?
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)
[0] https://www.arrl.org/files/file/Regulatory/Band%20Chart/Hamb...
Network gaming servers to the gNBs and every kid in the US will want a ham license.
;-)
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.
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.
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?)
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
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
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.
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)
[0] https://www.ecfr.gov/current/title-47/chapter-I/subchapter-D...
https://www.wouxun.com/radios/two_way_radio_kg-v98.aspx
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.
Probably the main issue is RF compatibility.
CBRS frequencies might work for that.
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.
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.
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.
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.
Even without a simcard, emergency numbers should still work if in range of a cell tower. IIRC that's a requirement of all 4g devices.
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.)
The question is why don't handheld radios have Bluetooth and USB-C data (some have USB-C power).
Only recently are some of the cheap radio brands coming with USB c charging. I'd love built in Bluetooth pairing.
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.
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’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.
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.
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.
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 :)
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.
Imagine all the data they could collect. I would probably even buy a subscription!
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.
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.
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.
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.
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.
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.
Allegedly that's easier for some or unbearably gross for some in comparison with soldering.
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
If learning some DIY skills isn't your jam, then maybe a DIY ham project isn't for you.
The compromise vs "buy some spectrum for 8 trillion dollars" is that you can't use ham radio for commercial (or musical) purposes.
Not sure if you mean building or designing and building. But QRP labs has some nice kits.
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.)
Plus you probably need a licence to transmit in those bands.
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
I just want something that takes battery cells.
Is there any way to enable this for iOS?
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?
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.
White pages had physical address too.
In practice, even today without published phone directories, lookup from name to address is readily accomplished from public records.
If you have put in the effort to avoid all of those vectors, then it's equally possible to use a safe address for your FCC registration.
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.
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.
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.
so long as you use it for an actual emergency, there are no issues
Its not great for over the horizon communication, but its pretty good at getting through trees and other obstacles.
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.
* 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.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.
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.
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.
It's a procedural thing. The FCC will tell you did it & tell you the penalties. Your options are zero.
Repeaters may use any method to limit access and control to authorized users.
(For some reason the radios are showing as $30 right now)
https://www.amazon.com/QUANSHENG-200Three-Frequency-Receivin...
Definitely don't try 27 MHZ, or perhaps outside of the above bands at all.
Are these Yaesu, Motorola, or Icom quality? No, but they're $25.
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.
I pretty much only use it for experimentation and receive.
The old Baofengs had that problem, not Quansheng which are actually clean and the harmonics are within FCC specs.
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.
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.
Well, let's just leave it at ham radio transceiver
When I saw the headline I was hoping someone had hacked the qualcomm modem and turned it into a software defined radio.
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.
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>.
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.
If anybody could do that, that would be a nightmare I suppose.
Unfortunately, in a locked down production phone, those modes are unavailable.
Turn your Android phone into a laser pointer (with a USB attachment)
Turn your Android phone into a bowling ball (by submerging it in resin that is then shaped into a bowling ball)
Turn your phone into X: 1) Start with a phone and X-module-w/o-UI. 2) Make an app with the UI 3) put them together