[TowerTalk] 40/80m dipole

[Bill Coleman]

On Mar 24, 2010, at 10:43 PM, Dan wrote:

> I would like to build and send to my son a coil loaded dipole for 
> 80/40m. He has about 90 feet space to hang it in. Has anyone information 
> on loading coil values and placement in the 90 ft dipole?

Sorry to respond to an old message.

I built just such a dipole last fall. I wrote it up on my blog here:
http://boringhamradiopart.blogspot.com/2010/02/trap-dipole-for-8040m.html

Mine came up to be 98 feet long. You can let the last few feet of each element droop down to fit in your space. I have about 105 feet in the clear, and used this technique to put up 125 foot doublets before. 

I've been very pleased with the performance of the dipole. It is low, at just 10-12 meters (33-40 feet), but works well, and on 40m has a definite pattern. On 40m, it is as strong as my rotatable 40m dipole at 50 feet. I often turn it to be cross-wise with the fixed dipole and flip back and forth to get the best signal.

Bill Coleman, AA4LR, PP-ASEL        Mail: aa4lr at arrl.net
Web: http://boringhamradiopart.blogspot.com
Quote: "Not within a thousand years will man ever fly!"
            -- Wilbur Wright, 1901