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HapHazard57

Tue Jan 05 2010, 04:37AM

Registered Member #2605 Joined: Tue Jan 05 2010, 03:25AM
Location:
Posts: 9

Hello all, I have been gaining an interest in electronics over the last few months and would like to learn more.

I've had this microwave in my garage now for the last few days and I'd like to somehow fasion it into a snow melting device or something. Ya, ya, I know magnetrons and capacitors are the purest form of evil and should only be messed around with by someone who knows what their doing, or a priest.

So anyways, my questions are:
1. What resources should I study to undertake such a project.
1.1 If there is already a list of said resources could someone link me to it? I poked around a little bit and could not find it(Take that Site Rules P2:B)
2. What project(s) would be recomended to gain some experience that would be relevant to microwave snow melting technology?
3. Is there a database or place to find laws relevant to electronic devices.
3.1 Where is it?
4. Taking into consideration the type of questions I've been asking, did I forget anything?
5. I got one, terminology... Jouls, flyback convertors, and other things you don't hear everyday. *strikethrough* found the wiki. (wasn't working earlier or something.)
kkthxbi

Mattski

Tue Jan 05 2010, 07:33AM

Registered Member #1792 Joined: Fri Oct 31 2008, 08:12PM
Location: University of California
Posts: 527

There was a recent discussion on modding microwaves which has some useful information in it:

Short story is: radio waves are complicated, and at the microwave oven power level they are also very dangerous. What I would consider the very minimum knowledge prerequisites before attempting such a project would be basic horn antenna and waveguide theory, at least at system level if not Maxwell's equations level, something about the material science involved, and reflection at dielectric and conductor interfaces.

I mention the material science because you would want to look at how much power would be absorbed and reflected by ice at 2.4GHz. I don't know the numbers offhand, but it's going to reflect (not absorb) quite a bit more than water does, since it isn't really conductive. So while I'm sure you can melt snow with a microwave, it's not going to work nearly as well as heating water, and more power will be reflecting in lots of directions.

Edit: You should also do some quick floorplanning analysis with regards to the approximate mass of ice that you want to raise by what temperature. This, given a rough assumption of how much power you transmit and what fraction the ice can absorb will let you know how long you have to run such a machine.

Bjørn

Tue Jan 05 2010, 07:40AM

Registered Member #27 Joined: Fri Feb 03 2006, 02:20AM
Location: Hyperborea
Posts: 2058

First you need to look at this to make sure your expectations are in line with reality:

Unless you own a power plant you should not expect to be able to melt a lot of snow in a hurry.

Read the relevant parts of the wiki, search the forum and the archives, if you spend a few hours you will get a reasonable idea of the electronic side of the project.

EEYORE

Tue Jan 05 2010, 07:44AM

Registered Member #99 Joined: Thu Feb 09 2006, 06:10PM
Location: florida, usa
Posts: 637

I am hoping this is a joke. Screwing around with microwaves isnt a very smart beginner project. I suggest an LED blinker and some RadioShack electronic kits before you cook your kitty cat's eyes with that uwave.

Google will be your friend as well!
Matt

Steve Conner

Tue Jan 05 2010, 10:51AM

Registered Member #30 Joined: Fri Feb 03 2006, 10:52AM
Location: Glasgow, Scotland
Posts: 6706

1. Put snow in a suitable microwaveable container.
2. Put in microwave, and heat on full power until melted.
3. Tip water out, repeat until your driveway is clear.

Renesis

Tue Jan 05 2010, 01:27PM

Registered Member #2028 Joined: Mon Mar 16 2009, 08:13PM
Location: Norway
Posts: 319

Beyond the purely technical aspect of this, which i wil definately leave to to someone else, i think you will get problems with ice in your driveway when all that water freezes again. Steves idea is by my viewpoint the best, even if it involves some shoveling, because you can easily handle the waste water afterwards. BUT, there are far better and safer options than microwave. The simplest is resistive heating, as is used in water heaters, floor heating, hairdriers and so on. Or even fire, lighting a bonfire beneath the melting box. The fastest solution is using steam or hot water, which could be preheated and thus be more suited for domestic fuse sizes. Here in Norway at least the maximum fuse size in 2phase installations is 16A (13A by next year), times 230V gives me a maximum output of 3700VA.

But in the spirit of 4hv i assume you want a more complicated solution, and if so i would suggest you look into inductive heating:

Heh, or you could ask if you could buy cduma's heating blanket

HapHazard57

Tue Jan 05 2010, 05:34PM

Registered Member #2605 Joined: Tue Jan 05 2010, 03:25AM
Location:
Posts: 9

EEYORE wrote ...

I am hoping this is a joke. Screwing around with microwaves isnt a very smart beginner project. You said you wanted to learn more about microwaves, it's good that you said you want to learn more about them first, they are dangerous. I see from your OP that you want to get some experience under your belt before you try this, thats good. I suggest an LED blinker and some RadioShack electronic kits before you cook your kitty cat's eyes with that uwave.

Google will be your friend as well!
Matt

fix'd

Thanks for your suggestion.

Arcstarter

Tue Jan 05 2010, 10:12PM

Registered Member #1225 Joined: Sat Jan 12 2008, 01:24AM
Location: Beaumont, Texas, USA
Posts: 2253

That was not handled very well, guys.

If you went to a new forum, wouldn't you feel a bit attacked if someone said "I am hoping this is a joke" or something like that to you?

You can 'say' you are not trying to attack him, but that is really not enough to make someone believe that you aren't.

No, microwaves are not safe, but express that point in a somewhat more friendly way. Then perhaps he will listen, and his cat will see the sun rise again. Not to say that you are not listening, and not to say all of the advice was wrong, it was just presented wrong. That is my opinion.

HapHazard57

Tue Jan 05 2010, 11:50PM

Registered Member #2605 Joined: Tue Jan 05 2010, 03:25AM
Location:
Posts: 9

Haha, anyways, after reading a few other threads where someone else asked how to do the same, and then reading the same general comments, I've decided to just scrap it.

*pulls out boxcutter*
This thread is now about coil guns! All previous questions apply!

(That's a "thread hijacking" joke if noone got it)

Edit to add:

Renesis wrote ...

But in the spirit of 4hv i assume you want a more complicated solution, and if so i would suggest you look into inductive heating:

That is easily the coolest thing I have seen in quite some time...

badastronaut

Wed Jan 06 2010, 03:27AM

Registered Member #222 Joined: Mon Feb 20 2006, 05:49PM
Location:
Posts: 96

Will ice even absorb microwave radiation efficiently?

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