I've had a few of the C-band dish actuators apart, and the leads going into
the gearbox were for DC motor power, and a feedback device which may be
either a potentiometer or a reed switch assembly that's aactivated/switched
by a rotating magnet disc.

If you remove the gearbox cover, the wiring should be fairly obvious.

The older actutors that I'm familiar with (1980s models) had an indoor power
supply (separate from the tuner) that was the power source for the motor,
and also had the reversing relays in it.
The feedback leads went to the tuner IIRC.

It's not entirely clear, what you described as the actutor only moves in one
direction regardless of the DC polarity change.
I think you are seeing that with one polarity, the actuator moves, and with
the other polarity, it doesn't move (not that it moves in the same direction
as the first polarity).

Inside the actuator tube there is a ballscrew, and since ballscrews are
easily moved by external forces, there needs to be a braking system to
insure that the actuator holds it's position.

The actuator tube probably isn't designed for disassembly, but there are
likely to be a pair of spring coil mechanical brakes wound to fit snuggly
onto hubs.
The ones I saw (when I used an angle grinder to disassemble the actuator),
were the type of brakes that hold a hub in the way that turning a rod
inserted into a spring will turn freely in one direction, but be gripped by
the spring in the other direction.

If water has gotten into the actuator and caused the spring coils to rust,
they aren't likely to be operating as intended.

--
WB
..........
metalworking projects
www.kwagmire.com/metal_proj.html


"mike" wrote in message
...
Long time since I've posted but I need some help.
I have a HTS (Houston Tracking System) linear actuator off of a C-ban
satallite dish. It has 6 wires coming out of it; 2 large (~16 ga.)
[red and white] and 4 smaller wires [od green, green, yellow and bare]
I'm pretty sure that the red and white are the power leads and the
others are sensor wires. I also think that it is 24 volts dc, here is
where I have been having problems; I can get the actuator to move in
only one direction no matter which wires I use for positive and
negitive. Is there a couple of the other wires that need to be dealt
with in order to make this motor turn in the oppsite direction? Any
help would be appreciated.

Mike