Terry,
IIRC, the Rohn literature specifies 40' bare tower as the max height
for tilt up. A Hazer (or the like) could then be used. Simplifies
antenna maintainance.
I tilted up 20' with a mid size satellite array on top. It's as much
as I'd chance.
https://www.flickr.com/photos/n3ykf/7584223098/in/dateposted/
Norm 5J0YKF
On Sun, Sep 17, 2017 at 6:11 PM, Terry Brown <n7tb@comcast.net> wrote:
> Hello,
>
>
>
> I am need of some help. I have five 10-ft. and one top section of Rohn 25G
> that I took down when I sold my home recently. I am building a new home and
> my wife has asked that I not have a tower that is much higher than the top
> of the roof and with a smaller beam.
>
>
>
> For background, I realize that my new setup won't be as good for DX as my
> last one. My goal is to enjoy an antenna with directional gain again. I am
> not a serious contester. I already have DXCC, etc., so I don't have a
> burning desire to work every DX prefix out there, but would like to work
> some DX when possible. My operating mode has gone from exclusive SSB to
> exclusive CW.
>
>
>
> My new QTH will be built on a hillside facing east. My tower will be in the
> backyard. The ground has a very slight rise to the west. My roof line is
> staggered with the highest point being a horizontal 4 ft. section 23 ft. in
> the air in the backyard. It is in the center of the roof line and across
> from where the tower will be. The rest of the roof on either side is about
> 20 ft. above the backyard terrain. The ground at the front foundation is
> about 5 ft. lower than the foundation in the backyard.
>
>
>
> My antenna will be the Mosley TA-33Jr. My rotator is a recently
> reconditioned Alliance HD-73 that I used to turn a Cushcraft ATB-34 for many
> years.
>
>
>
> I am almost 70 and realize that I really should put up a tower with a tilt
> base. My concern is how much load a Rohn tilt base for a 25G tower can
> carry. I am willing to have a custom built tilt over base made if
> necessary.
>
>
>
> My tower will be attached to the house 13 ft. above the ground. I plan to
> put a pully system to lower the tower attached to the side of the house 12
> ft. above the ground.
>
>
>
> I have two thoughts about what will work. In both cases, the beam will be
> about 31 ft. above the ground in the backyard and about 8-10 ft. above the
> 23 ft. max roof height.
>
>
>
> 1. Use two 10 ft. and one top section of tower. This will put the top of
> the tower 29 ft. above the ground in the backyard. I would be able to
> attach the tower to the 13 ft. level of the house thus leaving 16 ft.
> unguyed. I would have roughly a 3 ft. section of mast extending above the
> top of the tower where the beam is attached. I figure the weight of the
> tower, beam and rotor would be slightly less than 200 lbs.
>
>
>
> 2. Use one 10 ft. and one top section of tower. This would put the tower
> 19 ft. above the ground in the backyard. Instead of using another 10 ft.
> tower section, I would have a 2 in. aluminum mast, extending 13 ft. above
> the top section. This lash up would weigh less than the other one. There
> would be 6 ft. of tower unguyed.
>
>
>
> My preference would be option 1. I just have no experience in knowing if I
> can tilt over an almost 200 lb. 29 ft. tower with beam attached using a
> pulley system attached 12 ft. above the tower base. If this is possible to
> do, I would need to know if I would need to custom build a tilt over base or
> could use the Rohn 25G tilt over base.
>
>
>
> Thanks so much for the help. If I was 20 years younger, I would just put
> the tower in concrete and climb the thing as I have in the past.
>
>
>
> Terry, N7TB
>
> _______________________________________________
>
>
>
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