Re: CD's as director-reflector units?



On Jun 27, 12:45 pm, "Ken S. Tucker" <dynam...@xxxxxxxxxxxx> wrote:
Hi fella's
Let me know if I should go to another group.
We're doing experiments with UHF antennae,
design.
CD's have a conductive aluminum substrate,
and diameter in UHF range.
We got into experimenting with them and have
unusual results, some very good, using them
as reflectors and directors.
Anyone else screwed around with these?
Regards
Ken S. Tucker


I've never messed with them, but I used to have a microwave TV
antenna that used disks as the directors, or whatever..
That portion of the antenna was a long rod that stuck out of
the housing which held the driven element I assume.
The rod was filled with tube spacers and small aluminum disks,
one after another. So it's been used, but like I say I've never
messed with one, or even used the TV version I had. It was just
an antenna I picked up out of a bunch of other junk..
Just find one of those old TV microwave antennas that they
used to mount on houses, and you will see "disk" elements.
I don't see why the CD's couldn't do the same, but of course
they are tuned to one, or at least a fairly narrow range of
frequencies if they use the stock disc size without trimming.
I'm not sure of any advantages.. Maybe one.. The elements
are naturally good to go with either polarization. Seems you
would only need to change the driven element polarity to
change from one to the other. BTW, the one I had, all the
disks were the same size.. And they were much smaller
than a CD.. Maybe 2 inches dia max?
MK

.



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