How to power three microwave magnetrons from a low voltage power source

Fairly uneducated on capacitors; wondering how one might go about attempting to power three microwaves from a low voltage power source? Would there be any way of taking advantage of the capacitors inside to use a temporary charge to power it (much like a taser I suppose). It doesn't need to be powered for very long, nothing longer than 30 seconds to a minute at once. Is it possible?

You're thinking of a power inverter. I have a store-bought type that you hook up to a 12V DC car battery. It powers 120 VAC appliances. (Maximum 1000W.) During a blackout we ran a microwave oven from it. Since it depletes the battery quickly I had to start the car engine so the alternator kept it charging.

The inverter contains capacitors as you suggest but it also contains:
inductors
transistors and/or mosfets
probably a transformer.

It is not easy to construct an inverter yourself.

cryptolocker said:

... wondering how one might go about attempting to power three microwaves from a low voltage power source...

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Typical power demand of domestic microwave ovens is around 900-1200W each; for three microwaves, you will need 3600W max. Just to keep some headroom, settle for one with 4000-5000W capacity.

It will be tough to power them from low voltage. You may search for inverters used with solar panels.

I'm guessing an inverter with those power capabilities would be too large and/or too heavy to mount on a handheld device? Also, do you think that the short but incredible high voltage pulses a stun gun puts out be enough to pulse the magnetron? Multiple stun guns if needed?

Stun guns are a completely different beast; they produce a high voltage but perhaps only a few mA current. The two electrodes must make skin (more effective if they pierce the skin- dry skin has high resistance).

do you think that the short but incredible high voltage pulses a stun gun puts out be enough to pulse the magnetron? Multiple stun guns if needed?

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No; you need to consider the total energy output. 10kV at 1uA will not be fatal but 10kV at 10mA for 1mS will be fatal.

You are asking to power magnetrons from a mobile power source. "30 seconds to a minute" is effectively CW (continuous wave), no chance to take the energy out of a capacitor.

Magnetrons have about 70% efficiency, in the first place you are asking for a battery that can supply 140% of the required RF power, secondly for a respective DC/DC converter.

You didn't yet mention RF power amount or the purpose of RF power application.

Just in case let me mention that we don't allow discussions about weapon design or similar dangerous topics at Edaboard.

Look at it this way:

3 x Magnetrons of say 1KW each = 3KW
Allow for inefficiency (losses in the converter and magnetron cirucuits) makes it about 4KW
Allow overhead for safety and to cope with surge currents make it 5KW.

So you need 5KW of power. The current from the low voltage source is 5,000/Volts and is measured in Amps. For example from 12V you need 5000/12 = 416.6Amps.

A typical hand held battery has a capacity of say 2.5AH which means it can supply 2.5A for 1 hour. So with a 417A load it would last 0.006 Hours or approximately 0.36 Seconds!
Of course, the 1 inch diameter cables needed to carry the current and the cooling fans would make it difficult to carry and the battery would, if it was capable of such loads anyway (it wouldn't be) turn to vapor anyway. So it isn't really a practical proposition :shock:

Brian.