Dan,
I got real lucky and found a guy who was selling 400' of old Rohn 20 on eBay,
normally assumed to be "TV tower", for $20 a section. I used the tower to
build my version of ON4UN's single elevated radial 4 square. For insulators, I
used fiberglass rod that fit inside the Rohn 20 legs. For each element, I
stuck 20' of tower "nose down" into 5 feet of cement, inserted the fiberglass
rods into the open leg at 15' height, then stacked 6 sections of tower on top.
I used a 10' aluminum tube (1") on top as the "tuning" device. I could have
just used 5' as it turns out since my element ended up at 64' after tuning.
Since I had Rohn 20 left over, I used them at the center of the square (to
mount the phasing box) and the end of radial supports but you could use 2x4s to
save money. I used Dacron rope for guys. I'm a 225lb guy so climbing these
tower SHOULDN'T be done very often but to stack the tower and adjust the top
aluminum tube, I was very comfortable and have lived to talk
about it. ;-)
That was the mechanical side. I bought the DX Engineering 80 4SQR phasing box
and built the 75 ohm coax lines with big ferrite chokes on the vertical end. I
have been very please with it and it has withstood some pretty heavy winds with
no problems. I liked it so much that I built one for 160M but since I didn't
have 800-1000 feet of Rohn 20 left, I used top-loaded wires hung off my 160'
40M tower. It isn't quite as good as the 80M 4SQR, but I'm very happy with it
even so.
I probably have $1000 in the 80 so it wasn't cheap but a 4SQR can get to be a
BIG antenna fast and it will take plenty of time tuning it correctly to achieve
minimum "dump" power. Tuning to achieve minimum "dump" power maximizes the
gain and F/B of a 4SQR. ON4UN's book goes into all the math and calculous
explaining that but I just absorbed as much as I could and experimented a lot.
The less money you invest means you'll be experimenting a lot more but time and
eBay are going to be your best friend to keep this project within budget.
Good luck,
Bob K5WA
Houston, TX
On Wed, Jan 27, 2016 at 9:05 AM, Daniel Hileman <n9wx@hotmail.com> wrote:
> Hi All,
>
> I am looking for advice on material to use for an 80m 4 square.
> Looking for the cheapest way to build an 80m vertical. I have looked
> at towers,used utility poles etc. (Utility poles look like the best
> option so
> far.) Curious what you guys use. I know that it may not be cheap, but
> I would like to do the verticals as cheaply as possible and looking
> for your input. I do not have 70' trees to hang a wire from (hihi) as
> I know this would be SUPER cheap. ;-) Like I said, I do not expect it
> to be free, but
> $1,800 for an 80m vertical from "Zero-five" antennas is crazy, and
> really dont want to spend $3,000++ on a 4 square! Looking at options!
> lol. I know it's alot of aluminum,etc.
>
>
> 73,
> Dan N9WX
>
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