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How do I construct a maser? Answered

So I have mentioned before about my plans to build a HERF gun using a magnetron powered by a highspeed motor w/ permanent magnets that serves as a generator(it's driven by a minature gas turbine engine). But the issue of collimating the microwaves into a beam that can travel at least 4 miles without significant diffraction is an issue I'm still working on. Now magnetrons have an efficient of roughly 70%.  So here's the idea: The magnetron's output coupling loop(antenna) will be inserted into a highly tempered glass cylinder that is attached to the top of the magnetron and the cylinder will be filled with either hydrogen gas or (anhydrous)ammonia. The oscillating RF field will pump the gas molecules at their microwave region resonant frequencies(if I use ammonia that will mean I need the magnetron to produce peak power at 24 GHz)and stimulate microwave emission by the molecules(population inversion). Has this technique ever been demonstrated experimentally? I know that RF radiation can be used to heat up hydrogen gas into plasma but maybe there are some references to masers constructed in this fashion.


"a magnetron powered by a highspeed motor"?

Could you provide a link to the design you are using - I've never heard of a magnetron with moving parts.

I think the idea is to use the motor as a high voltage source to drive the magnetron.

Mmmm I don't think that's going to work. Power requirements are enormous.

richharris, the generator is coupled by an axle to a miniature jet engine that will rotate at several thousand RPM.

Kiteman, the magnetron has no moving parts. I plan to use a high speed motor with permanent magnets so that it can function as a generator which provides the electric power to the magnetron.

Have you considered/calculated the power necessary to drive the magnetron?

Focussing RF beams is done with a suitable reflector or alternatively with a shaped antenna (at microwave frequencies, 3 to 10 cms, a physical antenna is tiny) Your idea will not provide you with a collimated beam.