couple magnetron output into direct load 1

[noblefuse]

hello fellows, is it possible to properly connect the output of the magnetron into a conducting wire??.
what i did so far.
1. the antenae off the anode block appears to be 2,25 inches long. surprising not 1/4 wavelength, that was new to me. however, i believe it oscillates with respect to ground or metal shell of magnetron. i soldered a wire to the antenae without destroying vacuum tube, i then soldered other end of wire to shell of magnetron. the wire lentgh was exactly 10 times length of the antenae length(i was trying to approuch some kind of imppedence matching criteria).
2. i dont expect the 2.45 ghz as i now introduce an inductance/short/opon across the magntron, but i am hoping for some kind of high frequency device for power extraction.
3. if this is then possible?? i will then place an electromagnet on the back of the maggie and vary the applied magnetic field to see if the frequency is slightly adjustable.
4. not too many really good books on the finer details of magnetron i have found--can someone recommend the maggie bible.
thank you kindly
sam

 

[logbook]

There are a surprisingly large number of people playing about with magnetrons who visit this site. Try searching on “magnetron” on this site to see what the other posters has to say.

The length of the wires you are attaching should not be used to define an impedance. You need a load! The launcher is a matching device to the waveguide and then to the cavity. It will only be matched when loaded.

You should be using a coaxial output from the magnetron, not a pair of wires. The ratio of internal to external diameters will give you the impedance from standard formulae. You must first read the safety warnings presented on the other threads however. Then you need a load to terminate the magnetron.

 

[dontthinktwice]

Logbook is right. You are going to end up cooking yourself if you don't figure out what you are doing before you try stuff.

The bible for magnetrons is by Collins in the MIT RadLab series. If you are a student, you can get the whole series on CD for a reasonable price. There is another two-volume book that is good, but I can't remember the author's name right now. I will post it later when I remember.

What do you want to do with the power you extract?

 

[noblefuse]

thank you gentlemen for replying. my student days were in the eighties. once a cource in communication design with small chapter on microwave devices and waveguides, i now find myself with the need to couple the magnetron. i should have explained my situation better. i want the wire to be the load. of course a wire is considered an impedence at a particular frequency. my only intention with the wire is to extract the signal from the magnetron and impose the induced current onto the conducting wire. the actual impdence is simply not the 10 gauge wire i am using soldered to the magnetron(as this is also the size of the antenae wire off anode), but this conducting wire will have a mutual inductance as i couple it into a tesla coil. it is very interesting to read the descprition of the magnetron, in which a resonant cavity will oscillate with a passing of discharge current from cathode to anode and by the swirling motion of magnetic field, i see a close analogy to the tesla coil in which the spark gap is an closure of a switch and the residual energy left in the cavity is akin to the charged capicitor in a tesla coil with remaining oscilations thru primary inductor, and then ofcourse by mutual induction into secondary transformer. thus , my intention is to somehow drive a tesla coil with the direct output of the magnetron. i need to "match" the output to the appropriate length of wire i am seeking, this very wire will be the induced oscillating current which will be used to oscilalte the secondary of the tesla coil. the resonant frequency will of cource have changed because of my placing of an impdedence load in parrelel to magnetron, however, will the new frequency still be in ghz, this would be valuable. i appreciate your thoughts, also, in regards to safety, it is comical to watch us in the lab throw the switch 30 feet from magnetron with one hand holding simply holding an old microwave door in front of our eyes, and the other across the jewels--quite amusing however with the utmost desire to not to injure ourselves, but progress must continue, any other suggestions on performing safty is welcomed, thank you again
sam

 

[logbook]

High power microwaves should not be considered "line of sight" when confined in a room. You are going to get multiple reflections and it will therefore sneak up behind your simple screens.

I would say the magnetron frequency cannot be "pulled" significantly. It will stay where it started plus or minus a few percent (guesswork).

You output wire is not dissipative and is therefore not a load. It will act as a matching transformer but a tesla coil at 2.45GHz is somewhat doubtful. If your tesla coil is resonant at 100MHz it will not couple much at all.

This whole project sounds like something between suicide and homicide.

 

[noblefuse]

this project. i have a need to establish a voltage potential across electrodes of at least 1mev. i desire a frequency range within 1-2 ghz. i am unaware of commercial devices in this realm. if someone knows, please advise

thank you

 

[zeitghost]

Stunning.

Self immolation for beginners.

)

 

[Higgler]

Your two wire transmission line will act like an antenna and radiate energy, watch out for heat generation.

Not many people use two wire transmission at that high frequency. Hence, your power at the load will be less than what you expect. Keep your wires from varying in separation distance from themselves. You may want to change the wires to a finline transmission using FR4. Finline is like having a circuit board with copper on one side only, then etching a slot out of the center. Result is two identical halves of copper clad board. Impedance is usually 100+ ohms but varies with the gap spacing you've etched.

KCH

 

[nbucska]

The proper unit is mV == millivolt and not meV. Electronvolt is the usit of energy of an electron
accelerated by 1 V.

For 1 mV you don't need a magnetron -- I would check gunn-diode or similar device.



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[nbucska]

If you mean 1MV (megavolt == millio volt) , well, I would'
start by budgeting the research instutute about the size
of the Manhattan-project...



----------------------------
Please read FAQ240-1032
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