GHz signal of 1 Amp

Microwave oven and a metal ring?

--

John Devereux

Good idea but I do not think I can get 1 Amp.

This might help:

help:

Thanks a lot. Yes i think that will help.

help:

Do you know how much an Amplifier like this will cost??

Depends on the impedance level. Most microwaves produce 800W or more of

2.4 GHz--with a 50-ohm impedance, you only need 6% coupling efficiency to get 1A rms. Figuring out how much you actually got will be the interesting part...you could probably just run a bit of heavy coax to a properly designed probe, e.g. strip the braid off the last 3 cm of the coax to make a 1/4-wave probe, and be very careful about RF burns due to not grounding the coax shield or doing anything else idiotic. RF burns are much nastier than ordinary burns, because they're caused by RF arcs. They're typically third degree, with the smell of charred flesh--and because they're often very deep, they can be very slow to heal. (On the other hand, if you got hit by the same arc at DC or 60 Hz, you'd probably be dead). If you don't have anyone there who understands high power RF, buy something from AR instead, and forget everything I said above.

Cheers,

Phil Hobbs

Thanks! ;-)

Just out of curiosity, what's this 1 amp supposed to be flowing _through_?

Thanks, Rich

As others have asked, 1 amp through what impedance? 1 amp (rms) at 50 ohms is only 50 watts. If you think you can't get 1 amp induced in a metal ring in a microwave oven, you've probably never tried it (and then tried to remove the ring with your bare fingers).

A magnetron is a good way to generate a lot of microwave power cheaply, but it's possible you have other needs, too, that you haven't told us about. Does the frequency matter? How about frequency stability? How accurately do you want to control the 1 amp? Does the load change over time (e.g. as it heats up)? What, exactly, is the load? (I can fairly easily get you one amp out of my signal generator that can output only +20dBm, if it's through a load of my choosing. Using a quarter wave long transmission line resonant at the frequency of interest, made from copper pipe, I can transform the 50 ohm output to a very low impedance. 1 amp at 0.1 ohms is only 0.1 watts, or

+20dBm.)

Cheers, Tom

At zero volts? Sure! You just need a resonant circuit and a way to excite it.

So what _power_ level do you need?

--
Tim Wescott
Control systems and communications consulting
http://www.wescottdesign.com

Need to learn how to apply control theory in your embedded system?
"Applied Control Theory for Embedded Systems" by Tim Wescott
Elsevier/Newnes, http://www.wescottdesign.com/actfes/actfes.html

On a sunny day (Wed, 17 Oct 2007 13:07:35 -0700) it happened Efthimios wrote in :

One amp, and no other thing mentioned, could just be the collector current in a transistor. Could be a simple circuit.

you can use something like a large PHEMT or MESFET

Colin =^.^=

Efthimios snipped-for-privacy@gmail.com posted to sci.electronics.design:

First you have to be able to talk coherently about the task.

Efthimios snipped-for-privacy@gmail.com posted to sci.electronics.design:

How about you do some calculations instead of guessing and dismissing and disrespecting?

Efthimios snipped-for-privacy@gmail.com posted to sci.electronics.design:

help:

Twit, your schoolwork assignment is to design and cost estimate it by volume.

yeah it is more than possible .. can source an amplifier circa 75 watts output.. has extra head room so that you may take this output and apply it to NON 50 ohm physics test cells you are likely to have. Have significant exwepricne in this power level and physics est cells!

best regards,

marc