VHF/UHF antenna made from wire and PVC Very directional sensitive

Useful information regarding antennas for SDR products.
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bubblegumpi
Posts: 49
Joined: Fri Oct 14, 2016 11:41 pm

VHF/UHF antenna made from wire and PVC Very directional sensitive

Post by bubblegumpi » Wed Nov 30, 2016 10:03 am

The elements are 50cm copper rods for a wave length of one meter. The directors and reflector are single piece insulated 16ga wire stuffed into the pvc tubes. I guess the wave length is one meter but it might be lower then this because there are ~25cm wires attached to them and the coax. Originally I was going to parallel a piece of coax to each to further impedance matching but found that wasn't necessary. This antenna was really easy to build and seems to totally ignore signals that its not pointed at. Seems to have eight lobes; where you rotate 1/8 turn away from the signal source and the signal drops to almost nothing then comes back at 1/4 then 3/8th etc. I works so well that you will miss any signals you are not aimed at when scanning around.
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bubblegumpi
Posts: 49
Joined: Fri Oct 14, 2016 11:41 pm

Re: VHF/UHF antenna made from wire and PVC Very directional sensitive

Post by bubblegumpi » Wed Nov 30, 2016 10:05 am

Here is the antenna being rotated around from the top to bottom of waterfall. You can see it cutting in and out at 1/8 turn intervals.
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Devotech
Posts: 9
Joined: Mon Sep 19, 2016 5:32 pm

Re: VHF/UHF antenna made from wire and PVC Very directional sensitive

Post by Devotech » Thu Dec 01, 2016 9:56 pm

Do you have full plans or a source of the design?
I have a lot of noise I need to pinpoint, and the directional nature you are describing may be perfect for hunting the noise down.

Thanks

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