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Old October 17th 04, 07:33 PM
Thierry
 
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"Fractenna" wrote in message
...
Bull feathers. The leads would *obviously* (duh!!) screw-up the operation

of
the antenna (unless you're proposing fibre optic temp sensors).


Actually, the real problem is that the RF can screw up the very sensitive
probe.


Hi,

We can also do record such images in a lab. In a cold chamber (10°C or
lower) and sending +1 kW tunes in the antenna
I am sure that with a sensitive thermal device like those sold by
http://www.x20.org/ we can do it.

Thierry, ON4SKY
http://www.astrosurf.com/lombry


The trick is to do on-offs of antenna power, and register the temperature

on
the offs. The duty cycle must be adjusted so that the equilibrium

temperature
is being sampled properly. Most of the time, the temp drops noticeably

after 30
seconds to a minute. In some cases, the probe can be quickly attached and

then
detached during the off cycle.

It's fun to do. Som experimenting shows how to mitigate 'to measure is to
disturb' issues.

Best,
Chip N1IR