Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [magnetron]

A magnetron tube is a metal clad glass tube with a hot cathode in the center which is surrounded by a powerful magnet. It is a low-cost way to generate ~10 GHZ microwaves of high intensity but not a stable frequency. Good for cooking food but no longer used for Radar. The Klystron tube is a much better microwave generator.

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What causes loss of power over lifetime of a magnetron?

The power of a magnetron declines over time\$^1\$. While not noticable for most consumer applications (A 2000-hour lifetime would last over 20 years if the device is used only 15 minutes a day), this is a problem in industrial situations. What…
Joren Vaes
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UHF Tesla coil powered by low voltage?

I want to know if it is possible to use a 2.4 GHz magnetron as a oscillator for a Tesla coil circuit. The idea is to use a oscillating relay-driven step up transformer (12 V to 10 kV) and then charge a capacitor bank up, just to smooth the DC…
South African Railfan
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How is it possible that emitting electrons create alternating charges in the cavities of a magnetron?

In a magnetron, electrons are emitted from the cathode and create alternating charges in cavities (fig). These alternating charges produce oscillations in the cavities which result in electromagnetic waves. I know the working of magnetron but I…
Prerna
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Connecting microwave oven magnetron with coaxial cable (for a simple plasma torch)

I would like to try and build a basic microwave plasma torch using an oven magnetron. I've had experience with S-Band RF back in my physical chemistry days but am not liking the prices for waveguides. Is it possible/practical to couple a microwave…
nitrous dude
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What dictates the current drawn by a magnetron's anode?

Typically AFAIK in a magnetron from a commercial microwave oven, the cathode filament is heated by a 3.3V 10A supply, generating a cloud of electrons by thermionic emission. The anode cavity resonator is then supplied 4000V, at which point the gap…
Oliver Walters
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Can a lower voltage overheat a magnetron?

Background I am working on a microwave oven that starts to emit an odor after 2 minutes of full heating despite otherwise working correctly. The smell is the same as that "sweet", overheated coil varnish smell that anyone with much electronics…
kackle123
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Understand magnetron monitor circuit

I'm trying to understand the lightbulb monitor section of the following circuit, the 2200 uF cap, zener, choke, and bulb. Everything else is a standard microwave oven circuit. The magnetron will not pass current until the filament warms up, a few…
PWalsh
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Magnetron Working Principle

I was reading this simple description of magnetron working principle. Can you explain me why when electrons go near the cavities, they start to resonate at microwave frequency? I do not see the link between these two phenomena.
Kinka-Byo
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How is the frequency in the label behind microwave ovens determined? How could one measure the frequency?

It is very common online for people on youtube, forums, and other social media to bring up the following fun home experiment to "measure the speed of light" using chocolate and a microwave oven. To explain it, the proposal is that by putting…
Maximal Ideal
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Using a non-time domain equation for a nonlinear equation based device in QUCS

I'm trying to model a magnetron oscillator source in QUCS. I am only interested in the output of the magnetron, not how it is powered. Traditionally a magnetron is modeled the same as many oscillators, with a parallel RLC circuit attached to a…
kthaxt
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Drive a magnetron with low power via a CCFL backlight driver

[EDIT] My real question here is: can a magnetron from a microwave oven be used to output low power microwaves? If so, how can I achieve this? If not, what is a source for low power microwaves? In this context, low power means that I don't intend to…
iamnotgoodwithcomputer
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In what pattern does the electrons get emitted from cathode in thermionic emission?

We have structure with an cathode and filament at the center. A cylindrical shaped anode with cavities surrounds the cathode (fig 1). When the cathode get heated the electrons are emitted from cathode and move towards the anode. This is the…
Prerna
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Microwave oven: How can I temporarily limit the startup load?

Problem: It's a common problem for "NON-inverter" type microwave ovens to pop circuit breakers, and mine is no exception. UPDATE Jan 2021: Extension / power strip added, (mentioned below) has still eliminated this problem completely! I think I've…
DaaBoss
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How to generate microwave band frequencies like 85GHz? Is there a DIY device or parts kit to do this?

Let's say I want to build a device that generates and sends out a microwave of some arbitrary specific frequency to a short distance, say 1 - 2 feet. For example, 95 GHz. Is there a straightforward DIY way to do this? Buying some parts kit,…
emjunkie
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What does information on a 2m319J D622 magnetron label imply?

I been looking for a 2m319J D622 magnetron at reasonable $. I see the D622 also D623 and D625 ,, What do the values imply, I've been unable to find any info..
xtal
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