Does a device exist which can generate microwaves using heat (e.g. hot air) as a power source?
You could use steam (and a generator) to make a current, which, when fed into a microwave generator circuit will give you an output at the desired frequency.
Don't know of an existing device though.
Thank you for the help
Hot bodies tend to radiate energy in the infrared range unfortunately :(
Some teeny fraction of the emitted power will be in the microwave range, but if you depended on that you'd have lousy efficiency.
Heat + Water = Steam
Steam + Turbine = Electricity
Electricty + Magnetron = Microwave
Heat => Microwave
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