/tech/ - Technology★

>What would be a good radio frequency for point-to-point transmission of data without needing to go through the FCC?

Get an Ubiquiti AirMax or something like it.

>>944131

Cool. How well did it work?

433 mhz ?

you can find cheap radio modules for that, connect it to a pi or arduino or go full analog

>>944130 (OP)

>What would be a good radio frequency for point-to-point transmission of data without needing to go through the FCC

As long as you don't transmit beyond 150 feet or something, it is legal.

>FCC owns radiation

Land of the free

>>944130 (OP)

>without needing to go through the FCC?

Everything in the ISM band is loosely regulated. Title 47 CFR Part 15 defines allowed unlicenced communication.

Basically, you can build and use your own stuff as long you play fair (Reasonable about of transmission power, so you don't blanket others).

>>944172

No, the radiation is yours. FCC owns the silence.

Eh, I guess I'm not as lazy as yesterday.

>What would be a good radio frequency for point-to-point transmission of data without needing to go through the FCC?

>My guess would be the unlicensed microwave frequencies, but that's not good for transmitting through weather. Is there something near AM that could use the magnetic portion of a radio wave to transmit digital data legally like how AM does? The idea of a high-gain loop antenna on top of a pole for sending/receiving digital data seems intriguing.

You could try using the PMR 446 band with a 500mW transmitter, that's the band for cheap unlicensed walkie-talkies, and the 500mW is the transmission limit in that band, in a good day(at night) it can get some incredible distances.

>Have any of you guys built your own radios? If so, what kit did you use and how good was it?

Nope.

Does increasing antenna length or size do anything to affect the gain of said antenna or is it more complicated than just adding more metal?

the antenna size is determined by the band you're trying to use, by the wavelength, you're going to gain the most by having a full wavelength antenna, but depending on the frequency you're using, it's going to escalate very quickly, so most antennas are a harmonic fraction (a quarter, an eighth) of the full wavelength or a fractal.

Really, any piece of wire can recieve any frequency, but if it's length is an harmonic of the frequency it's going to have a noticeable gain on that particular band.

But you should be careful of adding more gain without thinking about it as it also makes the noise floor higher.

>What amplification kits exist that could be used for boosting signals coming from an antenna?

All of them

Wideband amplification? no problem.

Single band amplification? yep.

Single channel amplification? of course.

>>944179

That would be me. Radio space is very much a shared resource. I am offended when selfish individuals want to take this commons away from the rest of the public. This level of offense is really on the level of life and death because it is a resource that can support injured people in their rehabilitation to being well.

>>944309

You're a fucking autist.

You could have played the we need it in an emergency card, but those frequencies are already agreed on and are monitored by the relevant bodies.

>>944309

you're the reason i'm designing a traveling solar sdr balloon to loop earrape on all frequencies

>>944721

The government is very good at tracing the history of components used in electronics.

>>944785

lmao

>>944721

>ear-rape pirate b'loon

Yar, fucking fund it.

Radios are for boomers

>>953342

Everything wireless is radio

>>944785

Just make it nuke itself.

>>953731

>just

Have you seen the videos of government agencies recovering airline fragments? They will literally reconstruct every remaining component over the course of a decade until they have enough to figure out where it came from.

>>954199

They have black boxes for that actually orange coloured

It's simple to avoid that shit, delay the beginning of the emission some time and don't have GPS.

>>953342

Let's just throw away good technology, cuz boomers. ZOMG!!!! GUYZ ZUCKERBERG JUST INVENTED FACEBOOK DIGITAL RADIO 101010101011111010101010101010 MUH TUNES!!!!

>>944130 (OP)

Adhoc Wifi is probably the best legal way of transmitting data. AM and FM don't transmit digital data. They are both analog. There is such thing as HF digital modems, but they are like dial up modem speeds. You couldn't do wide bandwidth transmissions in HF without the FCC raping you with a plunger after they take away everything you own.

Aren't digital transmissions highly regulated?

>>954334

>AM and FM don't transmit digital data.

You don't understand what those acronyms stand for.

>There is such thing as HF digital modems, but they are like dial up modem speeds.

What is 4G?

>>954350

You can transmit whatever the fuck you want with an unlicensed PMR-446 that nobody is going to say shit about it.

>>954356

>PMR446 (personal mobile radio, 446 MHz) is a part of the UHF radio frequency range that is open without licensing for business and personal use in most countries of the European Union.[1]

I don't think this applies with the FCC.

>>954357

No it's the ECC.

Your equivalent band would be the FRS channels 8 to 14.

>>954356

>You don't understand what those acronyms stand for.

Please go educate yourself.

>>954467

How about you stop larping and go educate yourself?

>>944721

=do it=

>>944785

>not going to shenzen and buying all components needed there

Your worst enemy would be getting triangulated.

They could measure the signal strength and do a massive operation to find you because why not and the police have too much free time.

Next would be implementing ECC and autoatically correct corrupted shit like how packets work and other shit that ensures TxRx quality from bad weather or interferrance because you're trying to go in the digital realm.

Get Ubuquity like this anon says >>944132 to save you time then have a unlocked router that has many features but don't let the Land of the Free know about your router.

>>955124

>Leaving a peper trail of your trip

Salvage parts. scrub off anything that can be used to identify shit after palcing them and make your own PCB or don't and have everything via wires, it's going to be a mess but if it works it works, and give it an isoprpyl alcohol bath before sending it out, just in case.

>>955138

Nice suggestion anon.