Ron;
First, compare your county's wind load rating zone, ie 70 MPH etc..
Comtek 4-Square users have modified Hy-Gain Hy-Towers (24') by stripping
all stubs off and tapering the aluminum "stinger" so the vertical is
about 70 feet tall self supporting and or Rohn 25G sections.
For an insulated base, see www.mgs4u.com & click on Antenna Mart Catalog.
Their insulated bases available for 25-45-55G tower models.
Your best route is two 10' straight + one tapered top to give 29' of
Rohn 25G and a multiple tapered aluminum stinger, since Rohn discontinued
HBX type sections. You may have to consider Rohn 45G sections if in a
higher wind zone.
Follow Comtek's "Mid'Band" dimensions for both 3.5 and 3.8 use, as our
serious contest station users, without re adjusting any portion of the
array from a SSB to CW contest weekend.
Good Luck-73,
Jim Miller, K4SQR
http://www.comteksystems.com
4-Square Phasing, Stack Yagi
& Remote Antenna Switching Systems
On Fri, 5 Jan 2001 23:22:47 -0600 "Ron Stordahl"
<ron.stordahl@digikey.com> writes:
> I would like to put up a full size 80 meters vertical without guys.
>
> I will have space for a buried radial system of as many 1/4 wave
> radials as
> is needed for good performance. Would prefer an insulated base
> design,
> however I believe some successfully use a gamma match grounded base
> system.
> I would like to not have to tune it to cover from 3.5 to 3.85 if
> possible
> with max 2:1 SWR.
>
> The reason for no guys is to keep the neighbors and city planning
> commission
> happy, thus it would also be important that the tower be as small in
> diameter as possible consistent with the no guy design.
>
> This tower need only support itself. I will be hanging nothing on
> it.
>
> I would imagine the top would consist of a pipe section pushed up to
> the
> proper length to resonate the antenna midway between 3.5 and 3.85.
>
> Any suggestions?
>
> Ron N5IN
>
>
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