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Old 28-06-2020, 15:45   #1
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Bending VHF antenna

Is it ok to bend the VHF antenna to create an offset to avoid Windex and other masthead equipment?
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Old 28-06-2020, 16:18   #2
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Re: Bending VHF antenna

If you can bend it, the only effect would theoretically be in radiation pattern (assuming no radical bend). As a practical matter, any nearby conductive objects will also affect radiation pattern and can detune the antenna. If something is that close as to require bending it, it's probably too close.
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Old 28-06-2020, 16:34   #3
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Re: Bending VHF antenna

Do not bend as it is supposed to stick vertical for optimum pattern when the boat is horizontal.


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Old 28-06-2020, 16:46   #4
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Re: Bending VHF antenna

It depends on the bend!

One 10 degree bend is no biggie but two 90 degrees bends is a no no.

BTW, a mast head mounted VHF doesn't have to be vertical but it should be as close to vertical as practicable. You will note that it is rarely vertical when in use underway. However it does look silly at the dock if it isn't vertical!
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Old 28-06-2020, 16:46   #5
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Re: Bending VHF antenna

There you go Bob,

When you ask the internet for an answer, you always get “Yes, of course you can” and “No, absolutely not.” Wait a little bit longer and you’ll get “Maybe” as well.

I guess it’s back to you to decide!
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Old 28-06-2020, 18:44   #6
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Re: Bending VHF antenna

Maybe
Mine's been bent to clear the windex for 18 years with no discernable effects.
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Old 29-06-2020, 09:17   #7
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Re: Bending VHF antenna

Curious to know how much real estate you have at the top of your mast that the antenna would block the wind vane? You must have a tiny head at your mast or a huge wind vane. There should be ample room for the vane and the antenna.

And when one asks the internet for an answer, one usually gets replies that have nothing to do with the question. Gee... wonder how that works.
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Old 29-06-2020, 10:26   #8
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Re: Bending VHF antenna

Quote:
Originally Posted by SVHarmonie View Post
There you go Bob,

When you ask the internet for an answer, you always get “Yes, of course you can” and “No, absolutely not.” Wait a little bit longer and you’ll get “Maybe” as well.

I guess it’s back to you to decide!
Must have missed it - can you point to who said "no, absolutely not"?
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Old 29-06-2020, 16:40   #9
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Re: Bending VHF antenna

We have a price of extrusion about 15” long to keep the vhf away from the wind and flag
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Old 29-06-2020, 17:17   #10
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Re: Bending VHF antenna

OK here is another opinion, I bet if you bend it, you’ll never notice any reduction in performance, it’s there of course, but I bet it’s below the threshold of mattering in the practical world.
There are a lot of perfect things many say you have to have, like the thumb sized stiff Coax cable, but I’ve seen it used and there was no discernible difference, on paper sure, but not on the boat.
I can’t even see the silly thing from the dock, and I have a short mast.
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Old 29-06-2020, 17:26   #11
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Re: Bending VHF antenna

Bending an antenna will def affect the reflection in the antenna at least in the tests I have done with my Keysight Fieldfox. I was testing some antennas for IoT devices I manufacture that use knuckle joints. When I bent the antenna even 45 degrees it had a major impact. Whether this really matters to you is probably not that big of a deal in real world.

When I bent "whip" antennas, it did not seem to affect them, just the knuckle with a hard bend.
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