@@stujones3566 Same - really clear info on the LC circuit.

John, what is the power and frequency used in Marine radars ?

@@Mayosoftware Tesla level stuff man!

​@@JohnNy-ni9np sus comment

​@@JohnNy-ni9np...its adjustable for military purposes. Long range dissipation is very high. A so called horn focuses the beam. A ordinary sheet of aluminum foil can already protect 100% by reflection.

the Germans did

Yeah I've seen a guy comment on a similar video, he thought the oven stopped working so he put his head inside to check something out and he described the feeling as getting very dizzy, but nothing more serious. And it's the brain we're talking about, so it's definitely not that dangerous. And anyway it takes a while to get some heat to build up, with the brain thing it wouldn't be a surprise if the actual molecular vibration does something weird rather than heat alone.

In addition to the correct statements you and @Techalyzer have already made, microwaves also just don't penetrate that far. When cooking food, anything more than about 1" thick will heat much more slowly. For practical purposes, if you can arrange the food to reduce thickness, including putting an indentation in the middle of malleable solids like rice, mashed potatoes, etc., you can heat the food more evenly and quickly. For humans, this means that yes, some potential for injury exists if one really just ignores the pain involved before things get hot enough, but it's unlikely organs deep in the body would be affected much if at all.

I wonder if is this going on in Ukraine. During the Bosnian war very expensive anti radar site missiles would get to blow up decoys made of ovens rigged to operate with the door open. Probably the highest ratio of cost to kill ratio of any tech warfare kit.

@@echodelta9 Shortwave diathermy machines were used for similar purposes in WWII, though instead of disrupting radar seeking missiles they disrupted a radio beam intersect used by bombers. IIRC it was called the battle of the beams.

A good explanation.

Actually they do and the video explained that. Any electron that undergoes acceleration releases photons. He said the magnets were put there to make it "more efficient".

Actually I would be very curious to understand that "electron whistle". Would you have any links or explanation ?

it's about resonannnnnnnnce. RF is all about resonance, really. What frequencies and what proportions -- and especially geometry. The magnets provide a field for the electrons to surf against and curve into a spiral, it's together with the force of the electric field reacting against the uniform magnetic field that creates motion at a right-hand independent vector. The electric waves radiating out of the center would merely be attenuated by reflection by the LC tank of the copper cavity, but realistically I'd wonder if it would just cease to operate from damage overheating after a short time without the needed magnetic field to transform the radiated energy into EM waves with transmission capability.

Thanks for the explanation. This is truly incredible every day engineering that we take for granted.

Do gigatrons work in similar fashion?

That was kind of an old microwave that's why I tought it could still have... Better avoid it :)

Any dust are dangerous in high volume, maybe he breeze only few micrograms or less anyway everyone will die

@@ELECTRONOOBS I think it’s safe as long as you not breaking the ceramic

Beryllia is very white; a pink tint generally indicates alumina (aluminium oxide) ceramic which is much safer to handle.

@@ELECTRONOOBS it would have to be one of the very, very early microwaves to have BeO (The old Raytheon Radarange for example)

Nog een nederlander *G E K O L O N I S E E R D*

hahahahah thank you. The presence of a "static magnetic field" is actually just a pause in the animation while explaining. In real life it would be fast as you say, the field collapsing after the voltage passes the threshold.

@@ELECTRONOOBS You're welcome! Just wanted to clarify that an inductor's magnetic field will only collapse in this circuit when the voltage across the capacitor is zero.

I believe you got something wrong there, as the magnetic field is proportional to the current in the inductor, so the magnetic field has its maximum amplitude when the capacitor voltage is zero. Thinking if it in another way: Energy must be conserved, so when theres no cahrge in the capacitor (0 V) The energy must all be stored in the magnetic field

Good general advice for any power supply, really. For really high voltage stuff in the Navy, we had shorting probes and, in extreme cases, thick rubber gloves. I want to say protection up to around 30Kv with both. Which reminds me of an actual maintenance check documented in the technical manual for an air search radar I worked on, that dated back to the 50's or so. It was called the "tinfoil test" and was a way to test the "crowbar" circuit that was supposed to shut down the radar's high voltage in the event of a short. You would take a piece of foil and wrap it around the end of the copper rod of the shorting probe, fanning it out for a couple of inches. Then, you would glove up, open the cabinet to get access to the high voltage connection, connect the probe's ground clip, then bring that fanned out piece of foil, slowly, close to the HV connection. Before you make contact, it'll arc to the foil, burning a hole in it, until the crowbar kicks in and shuts it down. You then measure the size of the hole burnt in the foil. If the hole is too big, the crowbar was too slow, and it fails the test. I got to be first in my class at school to do that test. Makes a rather startling pop, too. 🙂

I used to repair microwave ovens. I've stripped lots of them. The reality is that if you test the capacitor, the voltage is gone in seconds. It's all BS.

To test a magnetron , you measure the voltage at the terminals. If the magnetron is dead, you'll get maybe 2.2KV and if it's good and drawing current it will drop to about 1.9KV. Got to use a high voltage 1000 times probe in the meter to measure

@@brolinofvandar super cool! Thank you for this share

⚡Bang! 💥🤣

While studying radio, I found Inductors and Capacitors are kind of opposites.

Hai i need help regarding usage of magnetron for waste management, plz send ur mail id

@@shanthalakshmik6884 Stop lying, there is no use for a magnetron in waste management. Fucking scammer.

Thank you for your comment. I'll look for that video.

@@cherylm2C6671 You're welcome. I'll post a link to the video in the next comment. If you only see one comment then it means KZfaq is blocking the link.

@@cherylm2C6671 Microwave diagnostic video: kzfaq.info/get/bejne/rJ5_ZrZqrZrQj5c.html

Thank you for your comment. What did you have to learn to start doing microwave tech?

@@cherylm2C6671 Quite a lot, I studied electromagnetism (Maxwell) and the maths in my own time, linear algebra and basic electrical theory. Our company was also working on the new X-Ray Tomography machines just coming into production. I worked in the section designing and making the cavities, so had to learn to use machine tools as well, to very high tolerances I may add. The smallest klystrons were used by jet aircraft in the nose cones, these were much higher frequencies (X band) but much less powerful.

@@tomctutor Thank you for your reply. I look forward to learning more about magnetron applications. Cookbooks now, theory eventually.

You long wondered how copper wire and magnets work? The schools suck today?

Thank you for your comment! Cleaning the interior often is a good insurance. Fat splatter gets hot enough to damage the protective mica.

@@cherylm2C6671 I used a plastic film on one of my ovens and it worked for many years with no visible damage. I think that mica is used just as a "worst case scenario", the area doesn't usually get very hot during normal operation.

@@techalyzer I will try that! Thank you for your suggestion! That will make cleaning easier than pushing on that mica plate. break. Fats (or bits of exploded egg) kept away from the magnetron.

What does ‘pounced’ mean?

@@2Sorts i mean if a hole appears, as shown in the video

Simple reason is cost and efficiency, magnetrons are over 50% effective at generating microwaves, and need no excitation at all, where transmitter tubes need both an exciter stage to drive them, and also filters on the output, plus the typical efficiencies of around 30% is a big drawback, and also the volume they need. Magnetron combines self exciting, and built in filtering cavity filters in it's design, so it is a single part.

What do you mean by "Radar vacuum tube"? Magnetrons _are_ vacuum tubes. Indeed, they are used for certain types of RADAR too. Klystrons aren't altogether too dissimilar in working principle either but they're specifically set up to be able to amplify a signal, whereas a cavity magnetron can only really act as a local oscillator. Handheld RADAR guns use solid state devices (Gunn diodes) and there are now power FET devices that can operate well into the mw band, but when theres no need for a high fidelity, low noise amplifier and all you need is raw RF energy it's pretty tough to beat the humble cavity magnetron.

@@whatelseison8970 The ORIGINAL vacuum tubes used for RADAR had a micro disc inside as the resonator with specific gaps on the inner circumference for the RADAR frequency instead of the size of copper chunk inside a microwave oven. It appears if you increase the size, triple the wattage you can achieve the same frequencies and higher without being in a vacuum.

Thank you for your comment. A radio science newbie is always looking for analog applications. There is still plenty of work for vacuum tube in the industry.

That magnetron is a vacuum tube till you cut it open.

Going to check it out now :)

Years ago i took the display/keypad/controller assembly off an old microwave oven and attached a power cord to it and hung it on the wall in the garage. Makes a great wall clock with count down timer and beeper all built in. Great conversation piece.

Alumina probably.

@@plainedgedsaw1694 Yes, only ever saw beryllia in military and avionics, where you needed the extra performance heat wise, and cost was not a driver. The place where you will find Beryllium alloy though in the house is in things that need fatigue life, like pressure gauges and clock escapement springs, where it is used with copper to make a very fatigue resistant alloy. World production of Beryllium is in the 200 ton per year range, and it is expensive, so no way will that go into a $20 magnetron made by the millions. The ceramic there in a magnetron is purple because they add chromium and cobalt oxides in small amounts to improve thermal shock resistance, and to allow the ceramic to bond well with the nickel and copper alloys used to make the outside envelope and the feed through terminals.

_"and the oven will work just fine again."_ -- well...not _that_ oven. But yeah, in principle it could've been repaired, before it was torn apart. :)

That's why you want to spin what you're cooking so the waves don't heat up one spot.

Back in the 70's, at ET "A" school in the Navy, I taught these things. Something like this video would have been nice back then. I made do with drawing a cross section on a chalkboard and trying to describe the electron flow that way. Animation is so much nicer. Our animation was Army films from back when radar was invented, mostly cartoons with sgts yelling and hearing echos. I always found the reflex klystron intriguing, with its re-entrant cavity. The visualization reminded of a popcorn popper, electrons flying up through the cavity, seeing the repeller plate, and reversing back to the cavity. One of the weirder devices, but kind of fun to teach. TWTs, on the other hand. We really only touched on them, and I never worked on them. Taught a brief segment on them, can't say as I really understood them that well, myself. I can say, however, I can remember having to change how we referred to them while I was there. The change happened as we started getting women coming through the school. Before, when we talked about TWTs, they were amplifying tubes. After, we had to refer to them as intensifying tubes. Because we used an acronym to refer to them, and I'll just leave it at that.

@@brolinofvandar Tit for Tat. 😲🤣

@@jlucasound Don't forget the 'W'.... 😀

@@brolinofvandar Known as Twits in my SatCom days, Did all the theory during my apprenticeship training, now long forgotten. Still makes me shudder working on water cooled klystrons, power off of course, but nevertheless, had to be done.