HFU HF Underground

Technical Topics => Equipment => Topic started by: bandarr3000 on April 12, 2018, 0048 UTC

Title: elevated vertical antenna -- radials?
Post by: bandarr3000 on April 12, 2018, 0048 UTC

I plan on installing a 20 meter vertical antenna, since my lot size is small.  I have a large tree in the middle of my back yard and around that tree is a platform/treehouse with the deck about 10 feet above the ground.  I can secure a telescoping mast to the deck and trunk below it, giving me the chance to mount the vertical starting at about 30 feet above the ground (I've taken into account branches and swaying, etc.).  Since this would be high above the ground my takeoff angle would be low which would be nice for dxing.  The question is: since it's so high above the ground, are radials practical?  It seems like the radials would radiate themselves.  Or, do I just need a good ground? Thanks.

Title: Re: elevated vertical antenna -- radials?
Post by: Stretchyman on April 12, 2018, 1125 UTC

Radials wont actually 'Radiate' but are needed to balance the system.

Since they are elevated they will need to be tuned, i.e the correct length.

You can slope them down at and angle and use them as guys for the mast too.

Try and fit a 5/8 if you can BTW.

Str.

Title: Re: elevated vertical antenna -- radials?
Post by: Looking-Glass on April 13, 2018, 2138 UTC

Radials enhance overall performance, try it with radials and then again without, you will see what I mean... ;)

Title: Re: elevated vertical antenna -- radials?
Post by: Stretchyman on April 14, 2018, 0712 UTC

It won't work Without radials as they're half of the antenna! It's just a (vertical) dipole, simple as...