"Jim - NN7K" wrote in message
m...
One consideration is that Magnetrons are NOT designed, normally for ccs
service-- they are designed for "PULSE" service, even the ovens- (duty
cycle of MUCH less then even .5) and, pulse transmissions arn't looked
favorably on many of the microwave bands any more.

Sorry if I am repeating stuff that you may have seen before, but I have
noticed things that do not seem to add up. For example the paper at:
http://www-personal.engin.umich.edu/...aes_tps04.pdf;
Shows the CW output of the magnetron spectrum as -10 dBm. Since for the
output is monitored via a 30 dB coupler, and a 30 dB attenuator I would have
expected the amplitude to be 0 dBm. It is hard to imagine such testing
being done with a grossly overheated magnetron. Having observed the output
of a microwave oven on a spectrum analyzer, it did appear to be pulsed,
although the spectrum was more characteristic of a frequency hopping (or
swept) signal.

Frank

In article ,
Anchor wrote:

* FYI:

o microwave ovens with the door closed already interfere with
most 2.4 GHz ISM band FCC Part 15 devices in close proximity

Agreed, and it's not too surprising. The FCC doesn't regulate
microwave oven leakage, and the FDA's standard limits leakage for an
installed microwave oven to 5 milliwatts per cm^2 at a distance of 5
cm from the surface. I've read that a fairly high percentage of older
microwave ovens leak more than the standard would allow.

That level could add up pretty quickly... a watt or more of leakage
from an older microwave oven would not surprise me very much. A
15-milliwatt Part 15 device can't compete.

--
Dave Platt AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

Here is an excellent and practical discussion of rough design and
practical use of can antennas, make sure to follow the link on the
bottom of the page...
http://www.turnpoint.net/wireless/an...coffeecan.html

John

"Anchor" wrote in message
news
Any suggestions on how to build a 2.4 GHz CW transmitter with a
microwave
oven magnetron and a 2.4 GHz "pringle" or coffee can style antenna?

There are tons of "pringle" or coffee can antennas or similar on the
web.
For example: http://flakey.info/antenna/waveguide or
http://www.turnpoint.net/wireless/an...coffeecan.html

I suppose one need only insert the magnetron antenna into the coffee
can
where one would normally mount the N-connector feed point.

A labeled diagram of a microwave magnetron can be found at:
http://www.gallawa.com/microtech/mag_test.html

I suppose the metal coffee can has superior micro shielding properties
relative to the aluminumized cardboard pringle can.

Would I be better off with plumbing copper drain pipe from the stray
RF
exposure perspective?

Since microwave magnetron use a half wave power supply, can I use two
magnetrons in the same coffee can powered from a single AC HV
transformer
with a pair of HV rectifiers to feed alternate cycles to the
magnetrons?

Greg, VE0ACR