Greetings to the list.
Maybe two years ago I installed a small prop pitch motor under an 80 meter
yagi with 62 foot boom. This yagi had chewed up three rotors previously
which will remain un-named. I thought my problems were cured with the prop
pitch. Well, not so.
Within the first year, the yagi started turning counterclockwise in the
wind. I would park it due north but overnight it would creep in a wind over
to say 330. OK, I would go re-orient the yagi and within a couple of weeks
it would creep over to say 300. All the while the rotor controller in the
shack would tell me it is still due north. So, I thought I better pin the
antenna to the mast. I did this but the creep continued. So, I pinned the
mast to the prop pitch rotor. The creep continued. Somewhere in that prop
pitch motor something is slipping but only counter clockwise.
I changed the prop pitch motor over to a spare that I had. The problem is
cured. No counter clockwise creep.
I disassembled the prop pitch and find that somewhere along the line a bit
of water go into the gear section but not bad. No bearings were rusted but
a sleeve was rusted pretty bad. I have removed the "gear sandwich" and all
gears down to what I refer to as the bicycle gear just above the motor and
don't see anything wrong. I cannot turn any gears by hand which is how it
should be. When I turn the motor shaft, all the gears turn.
Somewhere something is slipping but only in a westerly or counterclockwise
direction. Can someone give me some guidance on this problem. Rather
perplexing. What could it be?
73,
Charlie, W0YG..>>
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