On Mon, 13 Jul 2015 08:33:34 -0700, "Wayne"
wrote:
"Jeff Liebermann" wrote in message
.. .

On Mon, 13 Jul 2015 13:45:43 +0200, "bilou" wrote:

"Jeff Liebermann" wrote in message
...

Yep, antennas radiate photons.
+1
There is not any proof that RF behaves differently than light.
Things are already quite complicated without it :-)

One of my not so great ideas was to devise a contraption that would
let me "see" RF. It certainly would make troubleshooting RF devices
much easier. Essentially, it would be a human eye analog implimented
with RF components. According to theory, if it works for light, it
should also work for RF. At the time, I was working at about 1GHz.
Light is about 400 THz. So, all I need is an eyeball that's 400,000
times larger than the human eye. I'll give myself a -1 for the idea.

Wouldn't such a gadget be awesome for adjusting antennas!

Yep. I later realized that it would be marginal for RF circuits
because I could only see the components and traces that radiate RF. If
the circuit was any good, it wouldn't radiate anything.

I also burned some time trying to make an RF equivalent to a liquid
crystal sheet.
http://www.edmundoptics.com/testing-targets/calibration-standards/temperature-sensitive-liquid-crystal-sheets/1642/
Before thermal imagers became relatively inexpensive, I would place a
sheet over the power amplifier or whatever, and be able to see the hot
spots. I was also somewhat successful at creating a blurry thermal
image, using a small germanium lens and one of these sheets.

However, the ideal would be to have a liquid crystal sheet that was
sensitive to RF instead of heat. I couldn't find anything that
detected low frequency RF directly, but did get some interesting
effects by screen printing carbon squares on the thermal sensitive
liquid crystal sheets. The carbon would get slightly warm from the
RF, and cause the color to change. You can also use thermal crayons
to get a similar color change with temperatu
http://www.tiptemp.com/Products/Color-Changing-Thermal-Paint-Crayons/TLCSEN464-245-Color-Change-Crayon-Kit

Long ago, in High Skool, the instructor waved a neon lamp (NE-2) over
a transmission line, so that we could see standing waves. I thought
that was cool, but would be even better if a had a row of neon lamps
so that I didn't need to move the lamp. So, I built one with about
100 NE-2 lamps. Not only could I see the standing waves, but I could
also tune the load for minimum SWR. Today, I could probably built
something similar out of the LED strip lighting on rolls:
http://www.amazon.com/Triangle-Bulbs-T93007-Waterproof-Flexible/dp/B005EHHLD8
However, it would take more power to light up than the NE-2. At 4.8
watts/meter of LED strip, a 20 meter half wave dipole would require 48
watts to fully light at 10 meter long strip.

There are admittedly many things wrong with the aforementioned ideas.
None of them will work because of obvious (and not-so-obvious)
reasons. That's not the point. One has to start somewhere, and
started at "close, but not quite" is as good a place as any.


--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558