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Are microwaves bad for you?

gintonic said:
I intended both actually - with the former I am getting an increasing list of people on here who might need them. Actually I am sure I can source a delux sheep skin lined one for all the vegans!

I recall from my childhood TV programmes that claimed microwaves leaked microwave radiation and that they can cause cataracts......whether it is true I do not know.
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They would have to be spectacularly flawed in design and have large enough gaps in the oven cavity.
 
Stunsworth said:
Speaking of tinfoil, I once put some butter in the microwave to soften it up. What I’d forgotten was that the butter was wrapped in foil covered paper (Lurpak if you must know). The resulting fireworks were quite spectacular, as was the butter bursting into flames.
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it's actually a rather convenient way to heat up metalware when needed! with one proviso:
 
In my youth, working as a field service engineer for Tempo, we all had to take special training and learn how to use the microwave leakage detector when we first took them on as field service items. Everyone had their own leakage detector. Within a few years you only took a spare detector if you were changing the magnetron core - they never seemed to leak anyhow.
 
blossomchris said:
If the scientists at Sellafield do not use them, that is good enough for me.


Bloss
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I remember hearing this too. Was it because they caused interference with sensitive measuring equipment or did they upset some covert monitoring system?
 
linnfomaniac83 said:
Maybe so, but it’s true that they don’t leak around the edge of the door, the only way they would leak is if the grid were to be damaged... And microwaves only radiate from the front of a magnetron, not the back, and waves that do travel back will be reflected. If microwave ovens didn’t employ a deflector, you’d just get hot spots due to the directional nature of microwaves.
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We did an experiment at step daughters' parents day to measure the wavelength of microwaves with a piece of chocolate; something about a standing wave and the chocolate melted in 11.5cm stripes?

A long time ago but I know we won a planetarium (not the one in London, just a little domestic thing obvs)
 
Geoffrey Boycott had trenchant warnings about the danger of microwaves long before the internet existed

I remember him giving what was clearly an oftrehearsed rant on this subject whilst rain stopped play ....

For colonials reading this Geoffrey was a hi profile cricketer
 
timola said:
I remember hearing this too. Was it because they caused interference with sensitive measuring equipment or did they upset some covert monitoring system?
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Microwave ovens use a frequency of 2.45GHz and that is slap in the middle of the 2.4GHz WiFi band also lots of other kit uses this frequency band like video senders, cordless phones and car alarm sensors just to mention a few.

Cheers,

DV
 
gintonic said:
Gosh Tempo that brings back memories
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Not particularly good ones for me :) I had to take a job with them to get enough points to migrate to Australia at the time - I left a nice cushy office job building computers and networks (not recognised by Oz at the time - null points!) to become a consumer electronics (mostly TV and video) service engineer again with an area that covered most of London and South of England - 200-250 miles was the average daily travel from memory...at least no speed cameras back in those days...
 
I'm not clear what you mean by the "only radiate from the front of a magnetron". AIUI a magnetron will be a closed device with a guide / coax for the output.
 
Jim Audiomisc said:
I'm not clear what you mean by the "only radiate from the front of a magnetron". AIUI a magnetron will be a closed device with a guide / coax for the output.
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If you don't connect a longer waveguide, the electromagnetic radiation will propagate in all directions from the end of the waveguide built into the device which on its own cannot collimate the beam.
 
Jim Audiomisc said:
I'm not clear what you mean by the "only radiate from the front of a magnetron". AIUI a magnetron will be a closed device with a guide / coax for the output.
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Well they only radiate from the front because it has a wave guide. If course if microwaves were transmitted from a dipole antenna, they would prophegate in all directions but in the context of a microwave oven magnetron, they don’t, they radiate only from the opening of the wave guide. If microwaves were able to leak from the back of a magnetron, they would quickly destroy the circuitry that drives them... but they don’t.

On that note, the OP still hasn’t stated in which context he’s asking about. If we’re talking WIFI routers running on the 2.4 GHz band, it’s very low energy and it’s non ionising radiation, it won’t harm us.
 
I knocked up a bow tie and Schottky to check mine out a few months back as it has rusted through on the bottom in places... there was about 2V into 50R @1' which I deemed unlikely to cook me... I avoid hanging around in front of it though, just to be sure.
 
Arkless Electronics said:
I knocked up a bow tie and Schottky to check mine out a few months back as it has rusted through on the bottom in places... there was about 2V into 50R @1' which I deemed unlikely to cook me... I avoid hanging around in front of it though, just to be sure.
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That is the only risk with them though, a breach in the oven cavity large enough for the waves to pass through. Well that or if you rip one open and start playing... you can get a right whack off a microwave transformer!
 
A mere 1500V or so:D A cheap way of powering large triodes...

The circular "moat" in which the wheels under the glass plate run acts as a sump for moisture and this is where mine has rusted through in a few places. There is of course another steel bottom cover under this.
 
Arkless Electronics said:
A mere 1500V or so:D A cheap way of powering large triodes...

The circular "moat" in which the wheels under the glass plate run acts as a sump for moisture and this is where mine has rusted through in a few places. There is of course another steel bottom cover under this.
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MOTs deliver closer to 2kV, and with a good dose of current too, you really don’t want to be coming into contact with it. I’ve had a couple corrode in the same place, the moisture is from condensation. Leaving the door open for a few minutes after use will prevent that. If there we’re enough leakage to hurt you, it’d destroy the control PCB first given that it’d have to escape the outer casework to reach you.
 
linnfomaniac83 said:
MOTs deliver closer to 2kV, and with a good dose of current too, you really don’t want to be coming into contact with it. I’ve had a couple corrode in the same place, the moisture is from condensation. Leaving the door open for a few minutes after use will prevent that. If there we’re enough leakage to hurt you, it’d destroy the control PCB first given that it’d have to escape the outer casework to reach you.
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They are also very useful for nutters like me who use them to make a small Tesla coil. When you chuck out an old microwave rip out the xformer and flog it on evilbay.

Cheers,

DV
 
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