[TowerTalk] TX-455

[Bill Ogden]

> His 55 foot TX-455 US Tower is on the verge of collapsing down.  The
> owner just noticed that two out of three legs of his tower just broke
> down.   The legs snapped just above the mounting ears where the tower is
> fastened to the "T" mounting plate.   We suspect that some 90 km/h wind
> gusts we have had here in Toronto last week may have been a contributing
> factor.
>
> The tower is currently nested and the antennas are still on top of it.
> It is basically holding on only one of the remaining legs and a few
> cross braces.   It was installed brand new in 1990 and it had a 2 el GEM
> Qubical Quad installed ever since.   In 2003, owner replaced the short
> mast with a 22" cromoly nested about 3" inside the tower and added a
> home made rotary dipole for 30/40 m at about 10 feet above the Gem
> Quad.   The dipole is a modified Cushcraft D3W warc dipole.

>From this description, the very heavy (I assume) cromoly mast extends
about 19 feet above the tower. I assume this adds greatly to the turning
moment on the tower, even with relatively small antennas on it. Does
this exceed the tower specs?  (I have a TX-455 with a 10-foot mast, with
about 5 feet above the tower.  I have been thinking about a slightly
longer mast so I can mount a 30/40 rotatable dipole either above or below
my 3-element SteppIR.)

Bill - W2WO