On 12/29/2018 06:43 AM, William Gothberg wrote:
Shouldn't we have faster microwaves by now giving out a few kW? They
were invented decades ago.

I worked for a company around 1970 that developed a few high power
microwaves that were placed in area restaurants. The idea, now
completely familiar, was the restaurant could prepare quantities of
food, freeze them, and thaw on demand. Other companies had similar
industrial ovens.

The core business of the company was industrial plastics preheaters
which functioned at around 100 MHz rather than microwave frequencies.
They completely missed the consumer microwave market that was to grow in
the later '70s.

We always had a couple of the smaller preheaters hanging around
engineering. They did wonders for stale donuts. Even the factory workers
in the molding plants caught on. 'I bet if that thing can heat a
phenolic biscuit to 300 degrees it would work on my sandwich.' We didn't
explicitly mention it when installing new equipment other than vague
cautions about not putting aluminum foil in the cavity. The larger
models were 15 KW and could generate some Tesla quality fireworks.

As the various RF technologies like heat sealers made it to the
workplace a whole folklore grew up. Working around them could either
make you sterile or incredibly fertile, take your pick.

The technology has been around for over 50 years. What you find at Tesco
is what sells.