making a source of microwaves

[alan2here]

What is involved in making a week source of microwaves, something small that isn't attached to the steel box you'd normally expect a microwave to come with and with less power that runs of batteries but that produces micowave frequency electromagnetic waves?

[Klaynos]

Why?

[kanzure]

You're thinking of maybe a microwave gun, also known as the Active Denial System to the United States federal government.

 

Youtube.com video of a microwave gun

Homemade microwave gun tech video

How to make a microwave gun

High-power microwave system employing a phase-locked array of inexpensive commercial magnetrons (2006)

DIY microwave gun

etc.

 

Edit: Some more links, less related:

Giant review of microwaves

Microwave melting of metals

 

- Bryan

[alan2here]

Thanks kanzure, I shall look though all those links again later, looks kinda complicated. I have no microwave to take apart btw.

 

I was looking at experiments like the one of getting plasma from 2 half grapes and trapping it in glass and the one with exploding water in containers when there is a think layer of oil over the top and making sparks from metal objects and such stuff.

 

The reason for the battery power is that I don't want to be (am not going to be) using mains voltage for safety reasons.

 

I thought there would be possibilities for making something not as large or expensive as a microwave that could do interesting things with microwaves such as the grape experiment but in a way that is safe for the person buying it (like how a lightning ball is doing something dangerous but in a way that can be sold in a shop as a toy).

 

That video of the microwave gun exiberting such power over such range seems amazing. If I didn't want to make one I do now.

[imp]

Thanks kanzure, I shall look though all those links again later, looks kinda complicated. I have no microwave to take apart btw.

 

The reason for the battery power is that I don't want to be (am not going to be) using mains voltage for safety reasons.

 

 

Microwave radiation is generated in ovens using a magnetron tube. These require relatively high voltage to operate, around 1200 volts, as I recall. So, if battery power were the source, it would need to be raised to the magnetron's required operating voltage, anyway.

 

Incidentally, the reason microwave ovens seem very heavy is that they contain a large power transformer, whose purpose it is to raise the local voltage to that needed. imp

[John Cuthber]

magnetrons are not the only way to make microwaves. The Gunn diode

http://en.wikipedia.org/wiki/Gunn_diode

offers another possibillity.

Of course, a mobile phone is a battery powered microwave transmitter. The problem is that the "sparking grapes" sort of experiment requrires quite a lot of power and the only practical way to get that is to use a magnetron.

[alan2here]

Id quite like to see a video of someone firing a herf\microwave gun at something metal, I can imagine lots of sparks.

 

The water was good but it seems pity dumb firing at each other. I think thats quite harmful even if they don't realize it immediately.

 

I can imagine the cat in that video being out of view whiten one frame (maybe that wasn't trick photography), our cat would be if it annoyed\hurt him, but then again maybe not as he likes things I would think of as being too hot.

 

I think this article is about how you can make one with a Tesla coil, but the link in the article is broken.

http://slashdot.org/articles/99/09/10/0826258.shtml

[YT2095]

I would also Seriously think Twice about doing this too! with the exception of the Gunn diode, the HT versions not only contain more than lethal voltages, but the design aspects need to be considered also, as well as proper earthing!

 

sharp edges are a NO-NO! for instance.

 

you`re seriously playing with Fire here, and a few mistakes may be regretable, the others will kill you!

[John Cuthber]

It's a bit worse than playing with fire; you can see fire coming, the temperature sensors in your skin give you a fair (though imperfect) warning of fire and the hospitals are quite experienced in dealing with the consequences of cocking up when playing with fire.

[alan2here]

I have already stated that i'm not doing anything if it involves thousands of volts or mains voltage.