What to do with an old microwave?

jzmtl

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So I just retired my old microwave, it's a 800W that still works but seem to generate less than that (can't pop popcorn properly thou still heat food fine). The door sensor is also broken so doesn't auto stop when opened. What can I do with it, throw it out, or are there ant cool things I can make with the parts, or any other suggestions?
 

jrmcferren

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I smell a BIG rat here. The reduced output is normal and how a vacuum tube normally fails, in this case a magnetron. The rat I smell is the failure of the door sensor. A microwave oven as three sensors, the first two wire to the control board to keep it from turning the oven on the third is wired across the primary of the transformer, so if the other two fail or are tampered with a direct short occurs and the fuse blows. I would either send it to the relevant safety agency or the manufacture, this is dangerous and is NOT a normal failure!
 

yuandrew

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You can save the electronics/keypad and find something to use it as a "timer" for.

The transformer should probably give about 2000 volts on the secondary. There are plenty of High Voltage experiments/projects that you can look up on the internet of which you can use the transformer as a power supply for.

There would also be a large diode, a big mother of a capacitor (be careful around that, it may still be charged !) and finally the magnetron itself although your's is going bad.

You should also have a cooling fan, and either a "stirrer" or a synchronous gear motor for the turntable.
 

Black Rose

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So I just retired my old microwave, it's a 800W that still works but seem to generate less than that (can't pop popcorn properly thou still heat food fine). The door sensor is also broken so doesn't auto stop when opened. What can I do with it, throw it out, or are there ant cool things I can make with the parts, or any other suggestions?
Watch Discovery HD on Friday nights at 9:00 PM.

The Brainiacs have interesting uses for microwave ovens :laughing:
 

jzmtl

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Ohh, 2000 volts, is that enough for a tesla tower?

How large is the capacitor usually? I'm wondering if it'll be enough to make a capacitive discharge welder for batteries.
 

LuxLuthor

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Mount it on a pole and stick it in your front yard. Put a couple lights and sound devices in it. It will become a great conversation piece.
 

PhotonBoy

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Microwaves can be DANGEROUS!! I'd get rid of it as soon as possible, completely disabling it before discarding. You could get cataracts in both eyes if you view the insides while operating it with the door open.

From Wikipedia: http://en.wikipedia.org/wiki/Microwave_oven

"When injury from exposure to microwaves occurs, it usually results from dielectric heating induced in the body, the same heating that cooks food. Exposure to microwave radiation can produce cataracts by this mechanism, because the microwave heating denatures proteins in the crystalline lens of the eye (in the same way that heat turns egg white and so opaque) faster than the lens can be cooled by surrounding structures. The lens and cornea of the eye are especially vulnerable because they contain no blood vessels that can carry away heat."
 

jrmcferren

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Microwaves can be DANGEROUS!! I'd get rid of it as soon as possible, completely disabling it before discarding. You could get cataracts in both eyes if you view the insides while operating it with the door open.

From Wikipedia: http://en.wikipedia.org/wiki/Microwave_oven

"When injury from exposure to microwaves occurs, it usually results from dielectric heating induced in the body, the same heating that cooks food. Exposure to microwave radiation can produce cataracts by this mechanism, because the microwave heating denatures proteins in the crystalline lens of the eye (in the same way that heat turns egg white and so opaque) faster than the lens can be cooled by surrounding structures. The lens and cornea of the eye are especially vulnerable because they contain no blood vessels that can carry away heat."

I still say contact the appropriate safety agency and ask if they want to look at it. I know that microwaves can be very dangerous as can any radio frequency energy at that power level. Please take it from someone who is actually licensed for more power very close to that frequency such as me or most other ham radio operators. If the safety agency doesn't want to look at it ask the manufacturer (if they are still in business) as the failure mode you describe is supposed to be impossible without internal tampering.
 

jzmtl

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I know there is no internal tampering, because it was working fine but suddently became like that one day. Anyway it's now retired so I'm just trying to make the most out of it like salvage useful parts. It's several years old so I doubt the manufacture would care anyway.
 

Fallingwater

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Rip the transformer out and rewire it with two turns of thick wire on the secondary. Instant welder! :D

Or just leave as it is and have fun making sparks (do try not to kill yo' ***, though) :D
 

AJ_Dual

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Remove the magnatron, install it at the focus of an old large-style TVRO satellite dish, hook it up to your PC and start your own "active SETI" program.
 

Sub_Umbra

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"What to do with an old microwave?"

I've always wanted to gut an old MW and build a PC into it. I'd build it with positive air pressure cooling and filter all of the input air. The case would have great RF shielding. :D The LEDS would be visible through the tinted glass door. I'd put DVD drive, etc, inside -- just open the door to access any removable media but usb/firewire. It would all stay nice and clean...and wouldn't look like a PC.
 
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NA8

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I've got one out in the garage. I cut off the power cord and turned it on it's side. It makes a great little table next to my paint can rack.
 
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