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View Full Version : Why aren't these guys dead by the end of the video? - Open Magnetron Tube



CCWKen
02-25-2015, 12:44 AM
https://www.youtube.com/watch?v=POGSEG20hkg

I stumbled onto this by accident but why aren't these guys dead? The microwave radiation has to be spreading all the over the room. There's a loose shield around the sides but it clearly lights a florescent bulb in the cone pattern. The guy is placing different articles near or on the tip and even melting glass. All with bare hands. And what is causing the flame at the tip? Partial plasma? :confused:

They're not speaking English so I guess the comments didn't make sense to them. :)

dp
02-25-2015, 01:09 AM
Microwaves are mostly harmless under those conditions. Things change when the microwaves are contained inside a chamber because of proximity and reflections. The MW energy is contained and absorbed by certain materials in the chamber. Water being an excellent example. Standing in a radar beam can, if you are close enough, warm your eyeballs to an unhealthy level. It has to be a hell of a lot more powerful than the kinds of radar you find at the local yacht club. These kids are in more danger from electrocution than microwave damage. Unless they try to warm their hands by holding them close to the radiator. That can create sudden heating.

macona
02-25-2015, 04:33 AM
Yep, the most you would get is cataracts from long term exposure to microwaves. This is not ionizing radiation.

CCWKen
02-25-2015, 08:29 AM
Well cripes! Apparently, I've been mislead all these years. Why were they scaring everybody 30 or 40 years ago into buying those MW detectors to check for "bad seals" and leaking MW radiation? They made it sound like it would cook your brain and your face would fall off. They must have sold millions of them. At the time, I made my own from a small diode. It was publicized about as heavily as "Don't smoke or you'll die". And now we're finding out that you need fat cholesterols to be healthy. Coffee is bad, coffee is good. Chocolate is bad, chocolate is good. Seems like everything changes from one year to the next. :)

Oh well. I guess the longer you live the deader you get and there's no way around it. Thanks for bringing me up to date.

michigan doug
02-25-2015, 08:36 AM
" They must have sold millions of them."


Yeah...that.


Hey, microwaves are new. Let's tell people it's super dangerous and then make a killing on the magic detectors...


I think the russians make a handy little hand held microwave emitter to kill people without leaving an obvious mark. Push it up against the guy's head and push the button. Cook a nice chunk of his brain and then walk off. No sound, no muss, no fuss.


doug

J Tiers
02-25-2015, 08:44 AM
Those things exist because there ARE legal limits on the radiation from a microwave oven. If you worked in a restaurant and ran one with the door open every day, standing right in front, you would *probably get some damage* to your body.

The unit would be cheaper with no door and no interlocks, so that's how they would be made if there were no limits.

Somewhere between that and zero was established as the limit for allowable leakage from a device that is used by nearly everyone every day, AND can obviously damage people, since it cooks food.

Rather than trying to establish just how much "cooking" of the user was OK vs too much, the limits were made well below that kind of level. And so the detectors are made to find that level.

Marketing them to consumers is probably pure money-making hype, having the limits and detectors exist is not.

davidh
02-25-2015, 08:49 AM
" They must have sold millions of them."


Yeah...that.


Hey, microwaves are new. Let's tell people it's super dangerous and then make a killing on the magic detectors...


I think the russians make a handy little hand held microwave emitter to kill people without leaving an obvious mark. Push it up against the guy's head and push the button. Cook a nice chunk of his brain and then walk off. No sound, no muss, no fuss.


doug


that could explain the condition we see a lot of in this world. . . . . .��

Weston Bye
02-25-2015, 08:59 AM
When I was in the Navy, working on airborne search radar, we would occasionally place a hand over the end of the waveguide to see if the radar was transmitting. Only felt a gentle warming, but I didn't chance it by leaving my hand there very long.

Forty years later my hands are OK, but some of my other parts...

QSIMDO
02-25-2015, 09:47 AM
When I was in the Navy, working on airborne search radar, we would occasionally place a hand over the end of the waveguide to see if the radar was transmitting. Only felt a gentle warming, but I didn't chance it by leaving my hand there very long.

Forty years later my hands are OK, but some of my other parts...

We were on a tug made up alongside a visiting French destroyer.
A Chief was standing next to the wheel house and started to convulse, the glasses seemed to blow off his face and he fell in a heap on the deck.
The explanation that came down was the destroyer forgot to turn off their radar and par-boiled the poor SOB.
I dunno, I was an Engineman.

Weston Bye
02-25-2015, 09:50 AM
We were on a tug made up alongside a visiting French destroyer.
A Chief was standing next to the wheel house and started to convulse, the glasses seemed to blow off his face and he fell in a heap on the deck.
The explanation that came down was the destroyer forgot to turn off their radar and par-boiled the poor SOB.
I dunno, I was an Engineman.

French fried?

sch
02-25-2015, 10:41 AM
From the limited speech ?Russian, certainly outside N America which too some extent explains the videos lack of attention to any gesture towards safety precautions verbally
or in the vid. The potato reminded me of an episode in 1972 when microwave ovens were rare. A nurses aide was attempting to reheat a foil wrapped potato and it came to
my attention when I saw smoke pouring out into the hallway through the top of the door. Inside the minikitchen was a layer of smoke 2 feet deep at the ceiling and the aide
punching another heat cycle into the microwave. When I pulled the foil wrapped former potato out it was glowing like a charcoal bricket and the non-glowing part was
completely carbonized.

QSIMDO
02-25-2015, 11:24 AM
French fried?

I'm so embarrassed I didn't think of that. :(

JRouche
02-25-2015, 12:11 PM
Magnetrons can be deadly. Mainly the metal bodied type, very high power. The metal body emits xray radiation. I was also in the Navy. We had some very high power mags and klystrons. The klystrons were even more of a danger from xray energy. Interlocks all over the cabinet to prevent accidental exposure. Although there was some preventative maintenance that required us to take voltage readings with the 50kv applied. But no HF so no xrays. Fun job. I sill have some large magnets from dead magnetrons. JR

Forestgnome
02-25-2015, 01:18 PM
Well cripes! Apparently, I've been mislead all these years. Why were they scaring everybody 30 or 40 years ago into buying those MW detectors to check for "bad seals" and leaking MW radiation? They made it sound like it would cook your brain and your face would fall off. They must have sold millions of them. At the time, I made my own from a small diode. It was publicized about as heavily as "Don't smoke or you'll die". And now we're finding out that you need fat cholesterols to be healthy. Coffee is bad, coffee is good. Chocolate is bad, chocolate is good. Seems like everything changes from one year to the next. :)

Oh well. I guess the longer you live the deader you get and there's no way around it. Thanks for bringing me up to date.

Pacemakers?

Paul Alciatore
02-25-2015, 02:31 PM
Dead? NO.

Able to reproduce? Well, ????????? I don't know.

When I was in the Army, there were stories of servicemen walking into the beams of high powered radar for birth control. Darwin had it right.

I worked with high powered klystrons for a number of years in my career: 25 to 35 KW size. About as tall as I am. They were fairly safe because they were wrapped in enough steel and copper and a water cooling jacket that no X-ray had a chance of getting out. The smaller ones were probably more dangerous, but not excessively so. The warning signs were probably more to ward off law suits. But I DO NOT recommend playing with them, large or small, unless you know exactly what you are doing. Same for magnetrons.

As for the damage from microwave ovens, yes it is real. It cooks your food. It WILL cook you; from the inside out. Kind of like opening your skull and sticking your brain in the oven. All parts of your body that are exposed to it will get hot. Not radioactive hot, just plain elevated temperature hot. You will cook, not glow. It's the same danger as a conventional gas or electric oven, but you don't have to stick your head or arm into it for it to happen. The radiation can bounce around the room.

I am sure the standards for allowable microwave radiation are very, very conservative. Neither the government nor the manufacturers want even one incident of harm from a microwave oven. And they probably have a better safety record than conventional ovens.

ldbent
02-26-2015, 01:04 AM
I, too, put a hitch in the USN 50 years ago. I was an ETR-2. A 2nd class petty officer who worked on radars.
My radar was an AN/SPS-29C. An air search radar that put out 250KW peak. The plate voltage on the output tube was greater than 20KV. The power supply for this tube had 2 each 18 inch tall thyratron tubes that glowed a weird purple and buzzed quite loudly. The pwr. supply cabinet had warning signs about limiting exposure that were ignored. Hmmm, I don't have children either.
The output tube was silver plated to reduce resistance at skin effect frequencies. The tube tarnished and had to be cleaned. The final step was wiping down with sick bay 190 proof grain alcohol that didn't leave any residue. I drew the alky from sick bay and was returning to my space via a passageway when I encountered an old BM-2(boatswain mate). He asked to see what I was carrying and I handed it to him. Some how he had recognized the nondescript can for what it was. Looking around and seeing no one, he quickly unscrewed the cap and knocked
back a couple without making a face. He probably was less than 45 years old but the booze, cigarettes, relentless sun and weather had did a number on him. He looked worse then than I do now at 70 and I'm no fountain of youth.
My brother was 18 months older and had joined the navy 4 months before me. He was an Aviation Electronics Technician. 1965 found him serving on ships of the line off the coast of Vietnam. He was temporarily assigned to fly drones for ships gunnery practice. While close ashore he was exposed to agent orange that had drifted seaward after being sprayed on coastal jungle. Move the clock forward 24 years and my brother has non Hodgkins lymphoma. Coincidentally, it's the same lymphoma found by the Defense Dept. at elevated levels among those exposed to agent orange. Of course our government denied all responsibility. Move the clock forward 10 years and my brother is dead. My brother fought for 8 years for his rightful benefits and finally won. The disease was more relentless than the VA.
Isn't it odd that present circumstances closely emulate those of times past. "Actions" that were enabled by falsehoods-The Gulf of Tonkin Incident and the Weapons of Mass Destruction. The extraordinary powers granted Johnson and Bush that resulted in debacle and tragedy. All for nothing.
It's a good life but you got to be strong.

dp
02-26-2015, 01:59 AM
50kv is at the low end of what it takes to generate xrays. Microwave ovens run at under 5kv. Xrays form a very small part of the total energy consumed in a vacuum tube - on the order of 1%. The commercial marine radars I worked on were 25 and 60kw with plate voltages quite a bit under that required to create xrays. Because of the PRF (pulse frequency) and short pulse length the average power was quite low. The pulse width is measured in microseconds and has be be less than the round trip speed of light to the closest desired target. The pulse energy for 3 miles is far less than for 60 miles. Marine surface scanning radar antennas have a very narrow beam in the horizontal plane but are quite wide on the vertical plane. This allows a ship to pitch and roll while maintaining a target. The degree of fanning reduces the energy/square foot and that energy fall off quickly with distance.

Xrays cannot be directed by the antenna feed be it coaxial or waveguide. None of the radars I worked with were ever placarded for xray radiation hazard. The only radar I ever worked on was on a Russian ship that had the transceiver in the wheel house and the antenna was feed by wave guide. It was a dual system capable of S-band and X-band frequencies. The x-band was fed by a waveguide that also served as the inner conductor of a coaxial transmission line for the S-band radar. It was inside an outer sheath that formed the shield for the coaxial line that fed the S-band scanner. With two magnetrons, two thyratrons, and two klystrons it was the densest cluster of VHV gear I'd ever worked on. It also had two vacuum tube IF amplifier strips. I had the distinct feeling the S-band radar was also an air-search unit. They're normally used to penetrate weather at sea that will block x-band frequencies, but this bugger was capable of far more power than the 25kw we normally see.

darryl
02-26-2015, 02:02 AM
Had a babysitter once who tried to light our gas oven. Took awhile to get it lit- gas flowing all the time- suddenly- POOF! She kind of got blown out of it, burned her hair. Dangerous bloody things- I'll stick to cooking CDs in microwave ovens.

Paul Alciatore
02-26-2015, 02:47 AM
And you trusted her with your kids?



Had a babysitter once who tried to light our gas oven. Took awhile to get it lit- gas flowing all the time- suddenly- POOF! She kind of got blown out of it, burned her hair. Dangerous bloody things- I'll stick to cooking CDs in microwave ovens.

darryl
02-26-2015, 03:02 AM
I was one of the kids- I tried to tell her how to light it, but she didn't do it right-