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Jimmy Wilkinson Knife Jimmy Wilkinson Knife is offline
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Default How do flatbed microwave ovens work?

On Sun, 03 Jun 2018 00:28:44 +0100, Rod Speed wrote:



"Jimmy Wilkinson Knife" wrote in message
news
On Sat, 02 Jun 2018 23:16:14 +0100, Rod Speed
wrote:



"Jimmy Wilkinson Knife" wrote in message
news On Sat, 02 Jun 2018 21:38:35 +0100, Rod Speed
wrote:



"Jimmy Wilkinson Knife" wrote in message
news On Sat, 02 Jun 2018 12:44:35 +0100, wrote:

On Saturday, 2 June 2018 11:41:57 UTC+1, Jimmy Wilkinson Knife
wrote:
On Sat, 02 Jun 2018 02:12:06 +0100, tabbypurr wrote:
On Friday, 1 June 2018 21:32:34 UTC+1, Jimmy Wilkinson Knife
wrote:
On Fri, 01 Jun 2018 21:25:40 +0100, Brian Gaff
wrote:

Back many years ago this idea was tried by Philips, their
microwaves with
the drop down door, and with rotating aerial rather than a
turntable. to be
quite honest it was rubbish and left cold spots in the food so
you
still had
to stop and turn the food.

I think the mistake is that the cavity is not moved in relation
to
the food
so standing waves still exist in the same places and only
moving
the food
relative to those is a true answer to this.
End of story.
Brian

That doesn't make sense. Spinning the pattern of microwave
radiation
must be identical to spinning the food. In both cases they are
rotated in relation to one another.

not identical at all. turntables produce much better evenness than
stirrers. Both together are best.

As I said, it's relative. The food and the microwave pattern are
relative to each other. Where the oven is and where the kitchen is
don't matter. If you rotate the food, or rotate the microwave
pattern,
PRECISELY the same effect is achieved.

I know you think that, you already said. And as so many have pointed
out
you're clueless.

Not one person has pointed out why one is more efficient than the
other.

I will, particularly with the microwaves with a built in meat
temperature
sensor. Clearly a lot easier to do those with the food not rotating.

And I can also see why rotating the food gets a more even distribution
of the microwaves into the food too. Harder to explain that one tho.

I see no way it could be explained. Two objects, the food and the
microwave pattern. Rotate one, rotate the other, same effect.

But you can't rotate the microwave source like you can the food.

Rotating some metal thing at the end of the waveguide
the microwaves are coming out of is nowhere as effective
as rotating the food as far as getting an even distribution
of the microwaves in the food is concerned.


Why not?


Basically because of the frequency used, you get standing
waves in the oven and some rotating metal at the end of
the waveguide doesn't have all that much effect on those;


I see. But Panasonic seem to think it works. Anyone ever compared the two as in how evenly the food gets cooked?

When they metal thing had rotated 90 degrees, so has the weave pattern.


No, because you get standing waves in the
part of the microwave where the food is.


Yeah I was (incorrectly) thinking those would change shape with the source moving, but I guess not.

Precisely the same effect as if the food had rotated 90 degrees.


No, a quite different effect as the food
moves thru the standing waves.

Please do explain and I will be happy to accept I'm wrong. I doubt
Panasonic will though.

With anything where you see both offered, there must be good reasons
for
both approaches and it can't just be habit/tradition when its been
going
on for 40 years or more now.

Price I would think.

Maybe. I've never had a good look at how the flatbed microwaves do it.

Most likely just put their dead ones in their wheely bin
and we don't allow people to put them on the footpath
for the council bulk collection in my council anymore, so
I have never had the chance to have a look at a dead one.


Makes you wonder why we pay council tax when they refuse to collect half
the stuff.


Ours doesn't refused to take it, you're free to take
it to the dump yourself, and pay $25 per tailer or
ute load, $10 per car or station wagon and they
have 2 or 3 free dump weekends a year as well.


You have to pay to dump it?! But you pay council tax to cover that. Plus they're getting the raw materials! They're conning you threefold!

But that doesn't work very well for those who only have
a car with the bigger stuff like mattresses, lounges, dead
fridges etc.


Find someone with a trailer, they allow those here. They (for some reason) charge commercial dumpers, like gardeners, tradesmen etc, but sensible tradesmen take the stuff in a trailer attached to their own car then don't pay :-) Or if you go in the last half hour before closing time, there's nobody at the entrance to charge you and you just drive straight in.

Our council is unusual in that regard tho, most councils here
do have a few days a year where they will show up with a
truck and pick up the big stuff that's left on the nature strip.


Not collecting stuff free is a silly idea - the poorer parts around here where people don't have cars, their TVs just get dumped on the nearest bit of land until the council comes to collect them.

Mine refused to collect an old portable TV for recycling,


Our dump has a 40' container you put
that stuff in that is replaced when its full.


Why should I drive all the way to the skip just for a 14" TV? It went in the normal waste wheelybin, **** them.

so I put it in the landfill bin and hid it under some normal waste. Would
have been funny if the tube blew when it was tipped into the lorry.


Our trucks that show up every week compress the
rubbish and that would normally explode the tube.


Ours compress too, but I don't think they're strong enough to implode a tube. The compression thing is a big thick rubber sheet, probably designed that way so it doesn't jam on uncompressable materials.

--
Reticulating splines....