Author Topic: Electrically Shortening/Adjusting a VHf antenna?  (Read 713 times)

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GreekMan

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Electrically Shortening/Adjusting a VHf antenna?
« on: May 23, 2018, 02:10:24 AM »
hi all!

is there a way to "shorten" a VHF dipole or groundplane, but not physically?

Like placing a ferrite bead on the root of the elements?

Tempstar

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Re: Electrically Shortening/Adjusting a VHf antenna?
« Reply #1 on: May 23, 2018, 04:22:03 AM »
Yes, capacitors in the Pf range. I have used a 15pf trimmer cap soldered across the connection at the antenna.
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GreekMan

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Re: Electrically Shortening/Adjusting a VHf antenna?
« Reply #2 on: May 23, 2018, 04:42:59 AM »
indeed. I should have thought of it myself.

I guess efficiency will suffer a bit

BTW, at what voltage rating?

Tempstar

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Re: Electrically Shortening/Adjusting a VHf antenna?
« Reply #3 on: May 23, 2018, 06:59:21 PM »
I used 100 volt
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