[TowerTalk] Rohn 25G tilt base tower possibility

[Terry Brown]

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