Thread: Dish reflector
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Old April 10th 09, 04:00 PM posted to rec.radio.amateur.antenna
[email protected] jimp@specsol.spam.sux.com is offline
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First recorded activity by RadioBanter: Jun 2006
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Default Dish reflector

Brian Howie wrote:
In message
, Art
Unwin writes
I made a helical end fed antenna that is inside a cone shaped
reflector
The reflector is made from 1/2" mesh steel with an aluminum foil liner
and connected to the braid of the feed coax. No baluns are used, just
direct connections.
I was surprised to hear signals from the rear!
I thought that a dish reflector prevented such signals getting to the
receiver. So what can be wrong with the reflector or can signals get
reflected back from the frontal area? Antenna is at a 40 foot height
Any ideas as to what the fault could be?


Diffraction off the edge of the reflector. It causes backlobes. It's
not a fault.

Brian GM4DIJ


Ask him the working frequency and dimensions of his "dish reflector".

Don't be drinking anything when you read his answer.


--
Jim Pennino

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