Thread: rf burn
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Old June 25th 06, 02:38 PM posted to rec.radio.amateur.antenna
Bob Bob
 
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Default rf burn

Hi Frank

Although ot answering your question I thought I might relate a recent
experience of my own.

I remember various RF burns over the years. I never however thought I
would have an issue with a 18dBm (100mW) 11GHz TX I work on in my
employment.

The fault was low output and I was doing an initial feel around with my
fingertips, not actually touching an active citcuit metal but looking
for excess heat. I then rested my finger on a small screwhead (maybe
M2.5) that held the PCB down neear the output stripline (after the MMIC)
and got enough of a burn that it felt like a static discharge spike one
gets from a nylon carpet. It was a whoppa and totally unexpected!

I never did try to reason why the burn happened. The screw was loose
about 2-3 turns so I am thinking a tuned cct of some kind with my finger
as part of the dielectric! Oh an tighting the screw solved the low power
problem!

Cheers Bob VK2YQA

Frank Alforo wrote:
If I touch the coil in my tuner while transmitting I get a painful rf burn.
But a bird can perch on my antenna wire while I transmit 100 watts and it
stays there seemingly without a care in the world. How come?