I took apart a Kenmore microwave in order to salvage the magnetron, transformer, and the HV capacitor. The transformers, HV capacitor, and the magnetron from the microwave are intact. Is it possible to make the magnetron work without the microcomputer panel?
Electronic – Magnetron and microwave
high voltageradiation
Related Solutions
- The problem with MOTs is the voltage is too low to make a sparkgap work reliably. A pair is just-about doable but still not ideal. A neon-sign transformer is an easier and safer transformer for a first-time coil.
- Insulation and /or spacing
- A ground with a low inductance path, and one that will not damage anything if it sees a HV discharge to it. i.e. not the ground pin on an AC outlet. Stake in the ground is ideal as long as the cable length isn't very long.
- You won't need to do any measuraments on the HV side. You will know if there is HV present - corona hiss, ozone smell, arc-overs etc.
I believe the way microwave oven magnetrons are wired is that there are two coils on the transformer more or less in series, one to supply the HV and one to supply filament. The filament doubles as the cathode and it has some series inductors to keep the RF from leaking out the power terminals. The HV return from the anode could just be the metal case as it is less than an amp. An inverter-driven microwave likely has the same setup, however the transformer will be smaller as the switching frequency will be much higher (60 Hz vs several kHz). The inverter should have essentially the same connection to the magnetron as the older style single transformer solution. Also, you won't be able to run the inverter transformer by itself, you'll also need the rest of the inverter drive and control electronics. I'm not sure if it will work without the front panel/user interface; it may be required to turn the inverter on and possibly select the power level in some way.
However, turning on a magnetron outside of a case is very dangerous. Not only could you kill yourself with the high voltage, the high power microwaves could give you serious burns as well as possibly causing interference and damage to electronic deivces. The magnetron could also overheat due to reflected power if it is not properly coupled to a waveguide.
Edit: Looks like the inverter microwaves operate on exactly the same principle as the older ones, just at a much higher frequency. You'll either need to keep the front panel or figure out what signal it sends to the inverter to turn it on.
Image from http://www.electronicspoint.com/threads/microwave-inverter.234684/
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Best Answer
Unfortunately, it is possible to make the magnetron work outside the oven, but as the comments have said, this is a really bad idea. Do not fire up a magnetron after removing it from an oven.
You recall what a microwave oven is designed to do? Heat food! Do you know what you are? A big bag of food.
If you are lucky, you might discover this with your hand. The skin has nerves, and a cooling blood supply, and you'd probably spot it warming long before the proteins begin to denature. If you are unlucky, you might discover this with your eye. The cornea has no nerves and no blood supply, and you'd probably spot it first with your vision going cloudy, as it does exactly what egg white does when you heat it. This would be permanent.
In terms of life-changing injuries, it's even more dumb than messing with lasers without goggles. Do not fire up a magnetron after removing it from an oven.
It's quite easy to take a magnetron apart with a screwdriver and a pair of cutters to release the two ferrite magnets. These are strong enough to be fun, without the bone-crushing danger of neodymiums, but they can still give a fold of skin a nasty nip, so keep them away from 8 year olds (sorry my daughter!)
Before you power up anything removed from the microwave, let me review different sources of high voltage, and the effects of their limited current or energy on the human body.
TV flyback - very limited current, painful shock
TV tube, charged - very limited energy, painful shock
Auto ignition coil - very limited energy, painful shock
Neon sign transformer - fairly limited low current, serious shock, but probably survive
Microwave oven transformer - high enough voltage to jump through clothes, currents to one amp, serious shock, probably die