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5 watts is a tremendous amount of power in our application. It should be reserved for the much larger UAV's that can not only carry the transmitter, but a battery of sufficient capacity to power it for a reasonable amount of time.

I offer it mainly for folks who already know that they need 5 watts of power to succeed. Most folks don't ;)

Regards,

Bill

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Be sure to observe all the safety issues. I hear that five watts of microwave RF can damage eyes.

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My UAV have 3 meters wingspan.

The video below was shot from a 21 foot electric RC glider with 200mw of RF power:

NimbusCam

nimbuslakes1.jpg

We were operating at the fringe of the systems capability, so this is probably not enough power for your application, but it just goes to show that we can usually get away with less power than we think.

Bill

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It may be my imagination, but I could swear I can feel heat around the antenna

Hehe, 5W is enough to be felt, just like playing with an open microwave oven :rolleyes:

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Microwave ovens generally cook with 500 watts and more. However, exposure to 5 watts is suppose to be done with safety in mind. Especially if the Tx antenna has some gain to it and you are nearby.

I have been told that our eyes can be damaged to excessive microwave exposure, even low-watt levels, but I have never bothered to confirm that. I would hate to find out the hard way!

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Aren't most microwave ovens in the 900-1000 range?? or is that just the amount of A/C Power it takes?

Matt

Freq of microwave ovens is 2450MHz... like our nice TX <_<

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Heeeyyyyy.... if I could modulate the output of my microwave oven... but no, my wife just saw the glint in my eye and told me to go back to the basement :D

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Heeeyyyyy.... if I could modulate the output of my microwave oven... but no, my wife just saw the glint in my eye and told me to go back to the basement :D

lol... had already thought about this, but I've never had an old oven at hand's reach to look inside.. maybe it's better for me and my surroundings :P

even at min power you would have about 90W of output power... just enough for a very long range ground control station :D

I don't think that the radio organisations would love that :ph34r:

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BTW, your video is excellent, I really love tail view!! :)

I definitely will have to put my system on a glider, on planes there are far too many vibrations at this location... :(

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...even at min power you would have about 90W of output power...

Would come in handy when you fly on cold days. ;) Or, hmm, why does my flying buddy smell like bacon? :(

FWIW, I understand that the RF power is usually fixed at one rate in the oven. In other words, the RF source is not operated in linear mode to control heat. Instead, the oven's 2.4Ghz magnetron is slowly pulsed on and off to scale the lower heating levels. You can hear this effect while warming up something at a lower cooking temperature.

There is a hacker underground that (among other things) create EMF disrupter devices from microwave oven parts. These HERF-like projects can "kill" an electronic appliance from several dozen feet. Some hobbies really help test Darwin's theories.

Here is a site that has a microwave oven HERF project: http://www.svbxlabs.com/pages/projects/herf005/

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Argh, duty cycle control.... OK, had not thought about this but it surely is simpler and cheaper to do...

This one is mad!

If I was playing with 1kW I think I would take a R/C and not come closer than 100m from the unit when it's working :unsure:

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