How to use radio/radio modems to communicate with random people?
How to use radio/radio modems to communicate with random people?
You know how sometimes in a show or a movie there is a character that has a "radio friend" that they talk to? Yeah that's what I want to do.
But I do not know how to so I came to ask you! Cheap, preferably.
Out of curiosity, I found this app on IzzyOnDroid, (which gave me the idea in the first place) Codec2Talkie that seems to be what I'm looking for but I'm unsure due to my ignorance.
A radio modem seems to be required as the app description dictates. I can find one somewhere no issue. But is this the correct approach? Is there a better way that I don't know of?
Yeah, ham radio. If I was doing it all over again, I'd go for the most basic SSB radio I can find that plugs in to a computer sound card - that should in theory be able to do anything reasonable. You'll also need feed lines, an amp and a large-ish antenna, which is where things get a bit more technical hardware-wise, especially if you're in an apartment or have something like an HOA, but it nothing you can't figure out.
And yes, a licence. So far I've found the requirements pretty reasonable in my jurisdiction, they relate to not frying yourself or your equipment, and how not to be a menace to other people sharing the radio bands. You used to need to learn Morse code fluently enough to pass a practical test, but most places have gotten rid of that.
Any recommendations for basic equipment for someone wanting to get into ham radio?
It can be daunting to get into the hobby, there are a ton of niches.
To start: where are you? I'm in the USA, so that's where my experience is.
License: required to transmit on the ham bands; you can listen without a license.
Range: are you looking to talk to people in your city/region? If so, a cheap "walkie-talkie" style (called "HT" in the biz --- best avoid "walkie-talkie") is a good place to start. These VHF/UHF (very/ultra high frequency) radios are affordable --- something from Baofeng(~$30) or similar will work just fine, though they are often looked down on (I have one --- for the price, it's great). You will have the most luck if there is an active ham scene in your area, in large part because they may have a repeater, which can greatly extend your range. Many regions will have scheduled "nets" where you just go around and chat.
If you're looking for the ability to chat with folks on the other side of the world, you'll want to look into HF (high frequency). This is much lower frequency, thus longer wavelength, than the handheld VHF/UHF HTs. So...the antennas take up a lot of space. Mine is 52 feet long, in the attic. And the radios are much more expensive (more like $1k new). ICOM 7300, Yaesu FT710 are popular entry level units (but you also need power supply, cables, and antenna).
That said: if you just want to listen to HF, the antenna doesn't matter as much at all, and you can use an SDR (RTL-SDR probably works?) for listening. You can probably also find a used shortwave radio that covers some of the HF ham bands.
Disclaimer that I'm still a noob, too.
I gave my main recommendation there, for transceiver. I haven't done the research to have a model or brand in mind, but a cheap SSB (single side-band) radio seems like it should exist, given that you can make such a device with just 7 transistors. Any remotely modern computer will be able to generate an audio signal that, when mixed up to RF the way a SSB radio does, will look like the mode of your choice. Software-wise, I've really liked working with GnuRadio so far.
Amps go for a lot more new, because they have to handle both radio frequencies and >100W powers, and do so without causing distortion. Ham radio is a dying art, so poking around for ones at estate sales or similar seems promising. 100W is generally the recommended minimum if you don't want to be frustrated.
For the feedline, assuming you're doing coax, the design tension is between bendability and DB/meter attenuation. For radio 50 ohm impedance is standard, not 75, so you can't reuse stuff from cable TV without transformers. (Impedance matching is very important, as you'll learn getting a licence)
For the various accessories you may need to connect cables, amps, antenna wires and maybe filters, Amazon. They even have the obscure stuff I've needed for my direct sample radio.
All the prefab antennas I've seen seem ludicrously expensive, given that it's a chunk of ordinary metal, so probably skip that and cut your own. Antenna recipes are all over the place on ham homepages. If you're doing a bunch of non-resonant antennas, a tuner will save you time, but they cost as much as an amp. Everything that works at the high-power end is expensive.
My recommendation would be to find a local ham group and see if anyone will let you use their equipment. In my experience, hams are very often excited to do this, they have a new buddy to play radio with. Many radio clubs have club equipment for members to use and often gather and set it up during events, especially ARRL's Field Day. There's nothing like getting hands on with working equipment set up by an experienced user to see what you really like.
Licensed hams can supervise non-licensed users, so you can get on the air before you have a license if you have a buddy with a callsign willing to let you at the controls.
Especially since OP asked about having a "radio buddy," I think this is the way to go about that.
What you're most likely looking for is amateur (ham) radio. The exactly regulations will vary by country, usually there's some sort of testing/licensing required (at least if you want to transmit, you can listen without a license)
I didn't look too far into it but it looks like the app you linked is basically a tool to let you use your phone as a controller for other radio equipment. You'd probably need to be licensed to actually use it, and there's a good chance the equipment needed is pretty pricey. Ham equipment can kind of run the gambit from handhelds that run from about $20 up to thousands of dollars depending on what you want to do with it. You're probably better off starting with some more standard equipment before you start trying to rig together other stuff controlled by an app.
There's a lot of info out there for free on the internet and plenty of books have been written about how radio, so there's a lot of resources out there to learn from, or if there's a radio club in your area (there usually is) you can show up to a meeting and ask some questions.
Assuming you're in the US (different countries again have different laws) there's a few other radio options if all you want is to talk to people who are local to you. You can get a CB radio (think Smokey & the Bandit or truckers talking to each other) some places have more or less people actually using CB radio. The range and capabilities are more limited than a lot of ham options, but you can usually count on a few miles of range, and sometimes it's nice to get a heads up from truckers about traffic issues and speed traps and such. I personally like to use them with friends in different cars when we're on a road trip.
There's also FRS radios, you can pick them up pretty cheap at Wal Mart, pretty basic walkie talkies.
Many of those FRS radios are also GMRS radios, there's a GMRS license needed to use the GMRS capabilities, not test, just a licensing fee, so that's something to be aware of.
MURS radios also exist, I honestly don't know too much about it, but it's another free, no-license radio service you can use.
Each of those have their own limitations and restrictions on what you can do with them, but in probably 99% of cases you're probably not gonna run afoul of the law if you don't try to modify the radio or do something obviously stupid and use it in a way that's not interfering with other people's uses.
like ham radio? i think you can find affordable radios to listen, but in order communicate i recall you need like a radio communication license. at least in the USA
Does it have to be audio? A meshtastic radio like what you get from https://www.lilygo.cc/collections/lora-or-gps will pair to a smartphone app (or browser app) and let you text with people who also have a meshtastic radio nearby. If you're in a reasonably dense area there may be several people chatting.
I can't recommend meshtastic enough. I have 2 radios and I get to chat with other like minded folks over off the grid encrypted p2p 100s of miles away.
There are at least three legal ways to do this. CB radio, ISM frequencies and amateur radio. I say legal because the radio spectrum is heavily regulated because every transmitter affects everyone else to more or lesser extent.
You can buy CB or ISM band radios and get started.
Amateur radio is a better option in my opinion. There are many more frequencies to experiment with, people who can help and people to talk to.
Amateur licensing is different in each country, but an introductory licence is often no more than a weekend course and exam. I know of nine year olds who have done this. It's not hard. No Morse code required either.
With such a licence in hand you can use things like JS8Call, CODEC2, Olivia, WSPR and hundreds of other protocols to communicate using just a radio and a computer.
Disclaimer: I'm a licensed amateur in Australia and have been since 2010. I hold an introductory licence, here it's called a Foundation licence, and have been having an absolute blast with all that I can do.
If you have specific questions, don't hesitate to ask.
You could throw one at someone with a message attached.
I realize this in not answering your question, but I thought you might like to know that some people share access to their antenna on the web at http://websdr.org/. This sdr webapp lets you listen to the airbands from their antennas basically, and each user can tune it to their own frequency at the same time.
