Tim and Jim are correct. A 40-ft boom on 20M is a little short for five
elements. However, someone once said that sometimes you just gotta use what
you got. So, if you have a fairly recent copy of the ARRL Antenna Handbook,
there is a design shown in the chapter on HF yagis for a 5-element, 20 meter
yagi on a 40-foot boom (520-40.yag on the CD that comes with the handbook).
There is also a similar design that comes with K6STI's YO software.
> -----Original Message-----
> From: firstname.lastname@example.org
> [mailto:email@example.com]On Behalf Of Tim Duffy K3LR
> Sent: Saturday, October 09, 2004 1:50 PM
> To: EL34GUY@aol.com
> Cc: firstname.lastname@example.org
> Subject: Re: [TowerTalk] Wilson 5 element 20 meter monobander
> Hi Mark!
> I had a brand new one of these in 1979. Its factory dimension
> performance was horrible. I was attending college at the time and
> thanks to hundreds of key punch cards I was able to model on
> the mainframe computers (optimizers were only a dream in the
> public sector) a 56 ft boom design which worked much better with
> 5 elements. As Jim, SM2EKM (He visited me about the time I
> extended the boom in 1980) pointed out, 5 elements on 40 ft boom
> is one element to many for that boom length.
> Tim K3LR
> EL34GUY@aol.com wrote:
> > Hello,
> > Does anyone have any experience with the large 3 inch 40ft boom Wison
> > monobander for 20 meters? Im wondering how well it works and if
> it was reoptimized
> > and what the new spacings might be? 73
> > Mark
> > W0NCL
> > _______________________________________________
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