Take a look at my antenna system on QRZ.COM
I used two 20 ft sticks of 1/4 inch wall 20 ft long aluminum.
( The center of one 20 ft sticks is mounted and hinged to
the top of the other 20 ft stick that connects to rotator
down inside tower. )
I have put two, 18" steel inserts at the points seeing most stress
The top antenna, a 56 ft long force 12 Rot Dipole weighing 25 lBs
actually flips down so one can work on it when strapped to top of tower.
The large yagi is a 210 lB SteppIR MonstIR
I went with this scheme to keep the total dead weight on the tower below
350 lBs
as the Small Prop Pitch rotator unit weighs more than a lot of commercial
rotator units with similar turning ability. A 20 ft stick of 1/4" wall
Aluminum weighs in at
40 lBs as opposed to a 22 ft chrome Molly steel mast that normally would
weigh in
at 160 lBs ! ( This masting scheme shaved off at least 60 lbs system
weight and luckily
we don't have bad winds to deal with normally in San Diego city area )
73, Dennis N6KI
WB4UNA@aol.com wrote:
>
>
>
> I have been using aluminum mast for along time. I have to say I have bent a
> couple but that was all my fault for over loading them. I run the hazer on
> both my towers. The hf tower the mast sticks out 18' out the top. I have a
> th7,a3ws,and a d40 on the mast. On the vhf/uhf tower I have a 617b2,17b2,klm
> 31'
> for 222 and a 30' boom on 432 . This is all on 20' of mast. It has 18' out
> the top of the hazer also.
> I have bent a couple of mast due to the load. I am using #80 6061 .25" wall
> stuff. I am going to install two more towers and will use the same mast on
> them because they are light weight . I have a supplier here close to me. I
> have
> also sold many to hams and they also have been pleased with them. They come
> in 20' sticks.
>
> Randy
>
> WB4UNA since 1970
> Carlus M. Randy Chavis
> 247 Goff Court
> West Columbia
> SC 29172
>
>
> BANDS : SSB,CW
> 10-160,6,2,432,220
> EM93KV
>
>
>
>
> _______________________________________________
>
>
>
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>
>
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