One of the locals used to have a 4L20 on 90 ft of Rohn 6.
It is a little on the 'light' side, but it was up for YEARS.
As I recall, Rohn 6 has flat plates with rounded edges mounted
vertically for steps and the legs are SMALLER in diameter than R25,
maybe 1 inch o.d.?
There were several manufacturers of TV tower that used
1.25 inch o.d. legs with same size tubing used as steps
where the ends were flattened and welded to the legs.
I have 3 such towers supporting 3 beams each at 55, 75,
and 80 ft. The main 'weakness' of these towers is that they
'twist and flex' more easily than R20 or R25 due to the
absense of any diagonal bracing. I guy those towers closer
(every 20 or 25 ft) than R25 and use guy brackets with torque
arms at the top and middle.
Bottom Line: I would not worry about a small 3L tribander on
40 ft of either tower, assuming it is guyed well. I would probably
use two sets of guys for such a tower.
Tom N4KG
On Wed, 25 Dec 2002 07:37:14 +0000 (GMT Standard Time) "Mike Brown"
<k9mi@arrl.net> writes:
> You guys really have my curiosity up now. I may be using a Rohn 6. I
> have
> 40ft of it up, and it was given to me around 6 years ago for helping
> take it
> down. It had some surface rust on it, and I was a bit concerned
> about it,
> but our local tower climber said to clean it up, and paint it, and
> it should
> be ok. He took it down, put it up, and has been up it quite a few
> times to
> change some things for me. The face of it is 11.5", which is close
> to Rohn
> 25, and I did buy a used Rohn 25 rotor plate that fits it ok. It has
> a TH3
> on it, plus a Comet omni 10ft above that. I'll put the link to my
> web page
> on here so if you want to take a look at it, I would appreciate it.
> Maybe I
> should think about replacing it in the spring! Thanks... > >
http://www.qsl.net/k9mi/antennas.html > > Mike - K9MI > > > >
________________________________________________________________
Sign Up for Juno Platinum Internet Access Today
Only $9.95 per month!
Visit www.juno.com
|