If you were to look at a commercially-made pivoting base for typical light
duty triangle-type tower (essentially conduit and zigzagged steel rod)
you'll see that the anchoring points need to be very heavy duty.

Slight wind loads at the top of a 25 foot tower can generate a lot of stress
at the base.

A base I saw at a local dealer was made with parts fabricated from 1/2"
steel.. 2 "legs" pivot, and one separates with a heavy duty latching
mechanism.

You will most likely need to take the tower apart/down (top first) to
install a proper pivoting base.

If the tower were oriented properly (one triangle point toward the wall), a
winch could be installed in the garage for lowering the tower away from the
wall.

You might be further ahead to rent or hire a bucket truck for an hour to
allow you to get up there to change the antenna more easily, and be done
with it.

--
WB
..........


"stryped" wrote in message
...
I have an antenna tower in concrete behind my garage that has my local
tv station antenna. It is a big yagi type antenna. It has been there,
both the antenna and tower, for 12 years. I am getting a little older
and dont have any help and to be honest, dont like climbing up it. I
think the tower is 25 feet ot so from it's top to the ground.

Would it be possible to make a hinge for this thing so I could bring
it down to replace the anteena? Can I do it now that it is already
errected, maybe loosening at one of the sections and pulling it off,
installing the made hinge then putting back on? Would I be able to
lift the tower and antenna by myself once it is pulled off to install
the hinge. I appreciate any help.