>The newer models are DC powered, the motor is mounted horizontally, and
>they have a shield over the top seal.
>With the older models the top seal is recessed about 10 mm leaving a
>recess in which water can collect, or rather be trapped and corrode the
>output shaft. This in turn causes the top seal to fail, followed by the
>top bearing. I have not had a chance to examine one of the newer
>models to see the construction and implementation of the top seal.
>I'm planning on, or hoping to build a motorized, crank up, tilt over,
>heavy duty tower this winter
Watch out for PST rotators in a tilt-over tower, because the water
shield over the top seal is only fully effective while the tower is
upright. If the tower is routinely tilted over for storms, it is
advisable to protect the rotator from driving rain.
73 from Ian GM3SEK
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