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/diy/ - Do It Yourself

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217474 No.217474 [Reply] [Original]

How can I make a gun which fires radio waves?

I can do fine tuning later, so technical details aren't necessary, but I'd like a general idea of what I will need.

>> No.217480

Is there a way to fire waves using a directional antenna?

>> No.217495

You will need a parabolic antenna to direct the energy in one direction. A satellite dish is arranged like this, a transmitter placed at the focal point of a parabolic dish.

>> No.217496

>>217474
Why? Really, there is no point. On the upper end of the radio spectrum you start getting into microwave bands, and they are deadly.
Think of it this way: Radio waves entertain your food. Microwaves cook your food. Also, microwaves are not part of the radio spectrum and are a completely different animal, even though they are used to transmit radio, gps, and tv from space to earth.

>> No.217501

>>217496

Of course, I don't wish to kill anybody.

I know that radio waves emitted at certain frequencies can have a low effect on peoples brains, even in subtle way. I'd like a gun that can fire these beams. I intend on testing on myself.

>> No.217516

This looks entertaining:
http://alectronics.blogspot.ca/2010/10/laser-audio-transmitter-introduction.html

Also, look to Amateur Radio (Ham Radio) for construction of a highly directional antenna.

>> No.217517

>>217501
Why not just repurpose that "gun" into a radio jammer, considering these may or may not be legal in your local area.

>> No.217521

>>217517
Not a bad idea. Also, why not get next to an antenna when it's transmitting?

>> No.217522

>>217501
Defeat all the safety switches on a microwave oven so it'll run with the door open, turn it on and stick your head inside it. That's what you're suggesting would be like, more or less.

>> No.217524

>>217522
> Defeat all the safety switches on a microwave oven
> microwave

Don't do that. Also, I've stood within feet of 5000 watt AM transmitters while in opperation and it does nothing. I can't say that about the microwave stuff.

>> No.217525

>>217524

What does the microwave stuff do?

I've never owned a microwave in my life, I have no idea how they work.

>> No.217529

>>217525
radio waves start at about 8 Hz and go up to about 1 GHz, Microwaves start about the 1 GHz range and go up to about 16 GHz or so. Indeed, they have more in common with light then radio. You know how light is reflected and absorbed by things on earth? The same for microwaves. We use this tech for "Molecular Exciters", commonly known as microwave ovens, cordless and cellular phones, GPS, sattilite tv, etc.

>> No.217533

>>217529

There's a lot of conspiracy theory/paranoia that radio waves screw with peoples heads. I don't mean in a "mind control" way, but that they can affect schizophrenics who are more sensitive to them.

Do you know anything about this?

>> No.217539

>>217533
It's well documented that certain fillings in teeth can pick up standard radio waves, if you are near certain crystals, sometimes you can hear radio. But schizophrenia? There was mention by a doctor a long time ago as being a "possible" link to radio, but that was not conclusive at all, just some brainstorming on his part.

>> No.217541

>>217533
A side note, my mother could here morse code transmitted from ships with her false teeth. LOL now woulden't that drive ya batty?

>> No.217553

>>217533
This "theory" is why people are for some reason upset about remote meter readers at that power and as companies are switching over to. States are passing laws allowing people to opt out of having them installed because despite no evidence of harm there are a lot of people upset about having a low power RF transmitter on there house. Even though they probably own a microwave or a cordless phone or a router or etc. I think Vermont is even passing a law were people that opt out wont have to pay extra to cover the cost of having someone come read their meter.

>> No.217554

>>217553

I'm not from North America, we don't have remote meter readers

>> No.217589

>>217553
Ya, now I see. The power companies are using 1 Watt transmitters on the meters, and they broadcast in the 2.4 GHz range. The government has all sorts of regulations for this, and they are deemed "safe". Indeed, friends, you all have at least 5 of these devices in your homes already. Wireless mice, routers, keyboards, doorbells, speakers, etc. My response to the meter thing is "who cares"? Because everybody has it. Also, a foolish company would base it's business on such flakey tech. Let them learn the hard way. As soon as they fire the meters up, someone will have hacked them.

>> No.217593

>>217553
Also, the meters are not low power RF transmitters. they are low power microwave transmitters. PLEASE do not confuse the two.

>> No.217610

The following are my posts, and to avoid confusion I'll namefag it.
>>217496
>>217516
>>217521
>>217524
>>217529
>>217539
>>217541
>>217589
>>217593

>> No.217659

>>217524
That was my entire point: What I suggested *sounds* like a bad idea because it *is* a bad idea, which is what I'm trying to get across to the OP: What he wants to do would be extremely dangerous to himself and anyone he points the thing at. Essentially he wants to use a parabolic dish to tight-beam RF at a target. If the frequency is high enough and the power is high enough, he could do serious, perhaps fatal harm to someone. Bad, bad idea, and since the beam could travel for miles before dissipating enough to not be harmful, anyone and anything in it's path could be in harm's way. OP, don't play around with this shit. HIGH POWER RF IS NOT A TOY, DAMNIT.

>> No.217664

>>217659
And I can't agree more. Except for what you are calling RF. Mw is not RF. But even that should be preceded with proper education. Try that Ham ticket, OP.

>> No.217826

>>217659

>>tl;dr thread.

Don't forget the FCC showing up for OP's nuts.

>> No.217837

Mw is not rf
All of my why
Need some pedantic word venn diagrams

>> No.217855
File: 1.37 MB, 224x178, 1335289526003.gif [View same] [iqdb] [saucenao] [google]
217855

Except for >>217837
This whole thread pic related.

>> No.217938

>>217529
>>217837
JFC let's see you cook your food with AM radio, wingnut! The properties are entirely different for RF and Microwave. End of story.

>> No.217942

>>217938
...lol.

High power broadcast stations can kill living things within so many feet of their antenna. RF burns are nasty.

>http://www.youtube.com/watch?v=FSYj2lEaxhY

RF is nothing more than electrical energy being turned into electromagnetic energy. It's still energy and still potentially deadly.

>> No.217945

>>217837
Read the post. Do some research. Don't be an uneducated fag. Because what you don't know WILL kill you. :)

>> No.217947

>>217942
That's right. Still, the physical distinction is there. And playing with either of them can result in harm to the OP.

>> No.217948

op there are these bitchin ass radio waves that come from the sun for free and can be used to cook and kill things on any givin day, they are called, get this, sun light, all you need is mirrors bro, look it up

>> No.217950

I work in RF and i don't think I've read a single correct thing in this thread.

>> No.217955

>>217948
Right, dude. We here on earth like to devide the entire spectrum up into sections according to physical properties. RF is the frequency range that was traditionally used for broadcasting on with old crystal radios and such. microwave is just below the uv spectrum I believe, and has more physical charictoristics in common with light then with traditional radio spectrum.

But seriously, this comment was funny, bro.

>> No.217956

>>217950
care to correct us then?

>> No.217957

>non-ionizing radiation
>dangerous unless you're nearby some fuck-off powerful Megawatt omnidirectional transmitter or directional kilowatt transmitter
pick one.

All it can do is heat up tissue via dielectric heating or heat up metal (at a significantly faster rate)

>> No.217958

>>217957
How 'bout traditional RF <1 GHz being different then Microwave radiation?

>> No.217959

>>217958
Different doesn't mean more or less dangerous. It's just more difficult to produce amplifiers, connectors, transmission lines, etc for higher frequencies.

This also means it's generally very hard to get high power high frequencies signals.

>> No.217960

MRIs place you inside a several kilowatt RF field and have had zero documented evidence of health problems over the decades they have been in use.

RF is not dangerous.

>> No.217961

>>217959
So, you are saying a 1000W HF unit is as dangerous as a 1000W microwave unit that I make coffee with?

>> No.217962

>>217959
>>217960
Both of these have been my experience. I am paranoid of the Mw stuff, though I've built a few horns for networking.

>> No.217963

>>217961
https://en.wikipedia.org/wiki/Dielectric_heating

Dielectric heating is proportional to frequency so it's "more dangerous", but like i said, unless you're right next to a 50MW Transmitter antenna, or inside of a microwave oven (or turning it into a directional antenna like an idiot) it literally doesn't matter. the power from say, a cellphone tower, is something stupid like 10 orders of magnitude lower (talking 10000000 mW versus 0.00001mW) then a microwave.

>> No.217966

>>217963
Ok, I stand corrected. "Dielectric heating is proportional to frequency so it's "more dangerous"." That's what I meant, so thanks for that.

>> No.217969

>>217966
Yeah, my problem is with people who think "RADIOWAVES ARE EVIL AND CAUSE CANCER".

Microwaves are dangerous, but only if you tried to stick you head in them (they probably wouldn't operate with the door open anyway) or if you turned them into an antenna.

>> No.217970

Concentrated RF is as dangerous as electricity. There's been numerous studies that people on very high power towers will get sick and dizzy. Because of the inverse square law you practically have to be on top of fm/am transmitters. As you go higher in the spectrum, the wavelength shortens, hense microwaves. They're a lot more directional, but take a huge amount of energy to transmit compared to radio. But it's all part of the same EM spectrum. Microwaves, like the one in your oven transmits at (for a standard 1100 watt microwave) 700 watts of power and most of the food is placed at less than a foot away. In comparison, most wifi devices operate on .1 to .5 watts at a max distance of 100 feet or less. Microwaves behave a bit differently at different frequencies, but in general they bounce around or are absorbed partially or fully by different materials.
Anyways, op wanted to make a radio gun without understanding that radio waves are all around us. The sun produces a lot of rf noise, most of which are filtered through the atmosphere. Honestly, if you want to cause harm, figure out at what frequency humans naturally resonate at, then transmit a directed beam that counters the resonation. Then you'll get a death ray in theory. Causing subtle changes to the brain is really difficult at a distance. There was some studies about people with electrodes in their brains having an effect on their thought process or having high powered magnets affecting them. How ever directed magnetism is a completely different topic. And without a magnetic mirror and some really scary levels of magnetism in the hundreds of tesla range i don't see that being practical. You could try something with ultrasound and two transmitters to heat an area of the brain, but at range with power and tracking your likely to kill the intended target. Hope this has been educational

>> No.217971

>>217969
Ya, I've dealt with up to 5000W AM and only 1W at 2.4GHz, like I said, the Mw gives me the creeps still. I don't think anyone ever got burned from less then 2 Meters for frequency, though.

>> No.217973

>>217971
Only thing that scares me is working on really high power amps or tesla coils, but tesla coils are more of an arcing danger.

>> No.217975

>>217973
Tesla coils? WTF for?

>> No.217978

>>217975
Why does anyone build them? Fun

I had been considering building one (Solid state you can "play" poor quality music on at deafening volumes) but you have to be really careful with those fucking things.

>> No.217979

>>217978
Lol sorry, I forgot I was in /diy for a minite. I was expecting something like "I could tell you but then I'd have to kill you" kind of answer. Anyway, I'm out for the night. See ya.

>> No.217982

>>217978
>>217978
>>217978
I want solid state tesla coils so much. Become a pro at making them. yeahhh

>> No.218042

Some one please explain coherently how radio frequency (RF) and microwave radiation are not the same thing. I'm not trying to start a flame war. I honestly tried looking for the answer. I Googled. I looked in the books that I have.

I want to know why everyone, all the text books, and the government, and science, lied to me. Why did those fascists tell me the RF spectrum goes from 1kHz to 300GHz? Why did those scum tell me the microwave band is just a segment of the RF spectrum? I hate those guys for lying to me.

Anyway, if it's as simple as everyone in this thread implies, please enlighten a poor Anon as to how these two things are different, or at least a good link.

>> No.218045

>>218042
They are the same thing. Just like light, infrared, ultraviolet, xrays, cosmic rays, etc are all part of the same EM spectrum. Microwaves just have different properties than lower frequency radio waves. Just like light has very different properties than microwaves. Just like you can get a tan with ultraviolet, heat up things with both infrared and microwave, but probably can't heat up food with radio or xrays/cosmic rays.

>> No.218050

>>218045
Thanks for the reply. Can anyone do what was requested in >>218042 ?

PurpleNurple?

>> No.218061

>>218042
Microwaves, as in your microwave oven, don't work simply by having a really high output power. They transmit at a frequency that resonates with a particular vibration mode of the water molecule. Also, the microwave oven reflects the waves so that there is a standing wave pattern in the oven. That means that there is a lot of constructive interference at specific points, which means that a lot of energy is deposited in those places. Zapping someone with a "microwave gun" isn't the same thing at all. You'd need immense power to do that.

>> No.218070

>>218061
True true true.

So now we're going to have a slew of Anons who know what they're talking about, but I'd still like to hear from Nerple, who claims to be (and I don't doubt is) this Anon >>217496
and states that microwaves are not part of the radio spectrum.

>>217496
> Also, microwaves are not part of the radio spectrum and are a completely different animal, even though they are used to transmit radio, gps, and tv from space to earth.
>microwaves are not part of the radio spectrum

>> No.218074

>>218042

Wavelength becomes comparable or smaller than the equipment (or human) size somewhere near the low end of the microwave band. This affects the practicality of different construction techniques. Also, human-sized objects start absorbing the radiation noticeably.

I guess these are the reasons behind the idea that microwaves are somehow different than "ordinary" RF.

>>218061
> They transmit at a frequency that resonates with a particular vibration mode of the water molecule

This is often repeated, but it is not true. Water has no resonance at 2.45GHz and there are microwave ovens which use other frequencies.

>> No.218076

>>218074
So do you agree that 'microwave' is a part of the rf spectrum?

>> No.218077

>>218076

Yeah, sure.

>> No.218078

>>218077
Smart Anon

>> No.218096

Fun fact: the human body's RF resonance is typically between 80-100 MHz

http://hps.org/hpspublications/articles/rfradiation.html

>Because of this resonance phenomenon, RF safety standards are generally most restrictive for these frequencies.

That's the lower half and just below the FM broadcast band btw

>> No.218105

>>218050
>>218070
If one follows the current textbooks, then you guys are right.

Look at the older texts to find the answers, also the dates of the legislation as to when mw was included in the RF spectrum. Say, Brittanica from the 1930's or 1920's. What you'll find is that government excluded the mw and higher frequencies for 2 reasons: too dangerous for civillian population and we're gonna keep this for military sonar and communications.

Fact: Government, under pressure from corporations and special interest groups, lumped mw in with RF and started selling the bandwidth to large communications companies. This was what in the early 1970's?? It would be easier to sell to the population if they included it with widely accepted RF.

EM spectrum is NOT RF spectrum. RF is a small part of EM spectrum. Only small parts of the EM spectrum are used to transmit RF on.

>>218070

Like I said, if you follow the new textbook, you are right. Now look at it this way: a ham operator broadcasts within a few yards of his HF antenna which puts out anywhere from a few Watts to several thousand. This is deemed safe.

And now cell phones have been found to cause cancer. Why? Because the Gov. decided to lump mw in with RF and fool guys like you into believing that all RF was the same, including mw.

>> No.218110

OP, in the US you need a license to legally transmit on most of the radio spectrum regardless of how you do it, and even then there are regulations as to what you can do with it. Other than uses for communication, they are illegal.

Radio wave "guns" can get you into a lot of trouble in most of the world, depending on how you have it set up and power/frequencies it does.

>> No.218111

>>218110
He's right, op. Smartest poster in this thread.

>> No.218121

I'd also like to add that the "low power" argument is not valid, and much like radiation from a reactor, the damage builds up over time. So, a 1/4 Watt mw transmitter is still emitting damaging mw and the charactoristics of the waves will still be the same as a 1000 Watt transmitter

>> No.218251

Lol whut? Microwaves are used for radar. Back in the 30s/40s people used to warm near radar transmitters not knowing it was harmfull. Gladly they never got cancer because you body has natural protections against cancer. Radiation is a different kind of energy transmission, but it is also natural and around us. It has to do with decaying isotopes. For example potassium is radioactive, therefore bananas register on geiger counters. The level of radiation is miniscule and not comparible to that of nuclear reactors, however your proposed theory would seem to indicate that chronic exposure to microwaves gives you cancer. I'm fairly sure that just about everyone today would have cancer if that was the case and or cancer would only exist for the past 30 some odd years. However it was called consumption in the days of old where they didn't understand what cancer was. There have been studies that show that exposure to low doses of radiation is actually benificial. I would strongly suggest you look up the inverse square law and read a lot more into the subject instead of your fanciful conspiracy theory websites.

>> No.218260

Ohh and also dipshit, sonar is soundwaves. Bats and dolphins use sonar. Nothing to do with radio whatsoever

>> No.218261

>>218251
eh no comsumption is the old name for tuberculosis. Cancer was well known as a common killer since prehistory.

>> No.218273

>>218261
True. My bad

>> No.218363

Oops, my bad. I have a life outside of 4chan and that was a quick post. I should have put radar rather then sonar.

> your fanciful conspiracy theory

If I'm a conspiracy theorist, then that would make you [[GASP]] a sock puppet? How much are they paying you? LOL

> never got cancer because you body has natural protections against cancer

That's why everyone dies of cancer these days?
>>218261
And again, explosive cancer rates since the 1950's. Sure, it's been there since pre-history.

Bottom line, "sock puppet dipshits", is that the effects of mw on the human population have gone untested, and there are cases of brain cancer from appearant use of cell phones. Not that I really care, I live in the country and don't jam blue tooth shit in my ear. However, from the paper trail and what not, I think I'd like to buy YOU one for yer birthday.

>> No.218432

>>218363
Just sayin'. Epic lolz!

>> No.218451

>>218251
Microwaves still wouldn't give you cancer, they'd just heat you up or give you RF burns (which are probably worse the cancer.)

>> No.218463

>>218451
And that's your professional opinion as... a Doctor?

>> No.218651

>Cell phones
>Cancer
>Non-ionizing radiation

Oh look, it's three things that don't have anything to do with each other!

>> No.218726

>>218463
not poster you are replying to but...

His info is correct. A microwave will not cause cancer, and no I am not a doctor. I work with microwaves everyday.

A microwave causes the water atoms in an object to quickly switch polarity back and forth. This switching causes friction, which in turn heats up the object from the inside out.

No cancer particles, or bad photons are being transmitted. lol

>> No.218946

>>218726
Yep. The eyes are especially at risk, due to the fact that they can't be cooled as easily.

>> No.219097

microwaves = radio
microwaves ≠ radio

Is this argument based on an old vs. a new FCC chart, or is it based on science that can be backed up?

>> No.220356

>>217969
So if I was a redneck who wanted to kill birds flying on my property, I could -in theory- build a directional antenna out of a microwave to aim at them and cook anything in the beam from the inside?

I imagine this is both incredibly dangerous and somewhat difficult, or the military would just be making guns that cooked people instead of blew holes in them.

>> No.220366

>>220356
The military has such weapons, but they don't use them, pboably because of the really bad press they'd get e.g.
US troops frying hundreds of hadji peace protesters with that sadistic magic weapon...

>> No.220368

>>220356

Just google Active Denial System or directed energy weapon

>> No.220372

>>220368
I'd be interested in knowing what would happen if you pointed an ADS at a sheep for ten minutes.

>Wikipedia article
>testing in prisons
Oh god. Who allowed this? Have they never heard of the Stanford prison experiment? There are going to be some badly burned inmates.