Hello Vincenzo,
the G5500 rotator requires 6 wires for azimuth (connection between the control unit and the rotator unit) and another 6 for elevation. 3 wires are designed for motor power supply and 3 for voltage from the potentiometer (angle sensor). It seems that one (or more) of the three wires connecting the potentiometer to the control unit is broken. Then the rotor moves up and down correctly, but there is no signal about the antenna position.
The connection between the potentiometer and the control unit must be checked.
One wire is used as ground, the other one feeds the potentiometer and the third detects voltage from the potentiometer according to the rotation of the antenna.
73
jarda ok2gz
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