The Rotor Unit was designed for a maximum of 10 pounds in antenna weight centered low on the Rotor. Large antennas with long booms that provide a long lever allow a small amount of external force to cause an up down rocking motion to the antenna. Never force the antenna system against the Rotor Unit. You will break something.
This is an indication that the antenna is off balance front to back along the length of the boom. The off balance antenna, epically if large, will cause more stress to the bearings and require more power to rotate it. It is recommended to balance the antenna.
The Rotor system will operate from 9 volt power source, but the drive motor in the Rotor unit is designed for 12 Volts. Operating on a 9 volt battery is possible, but only for the smallest of antennas. At 9 Volts input, the motor is getting less than 8 volts which is far less power than the motor is designed to operate from. The use of the 50 foot extension is not supported when running from under 12 volts. The IR losses can become too large keeping the motor from getting the power it needs to do the mechanical work asked of it.
An erroneous heading indication be caused from a number of issues. First thing to check would be that you properly set the Heading Calibration. If you are using a circular push-up mast make sure that the locks on each section are tight. When turning the antenna the mast sections can slip allowing the mast to rotate over time. Also verify that the mast to Rotor Unit, and antenna to Rotor Unit mountings are tight. Finally you can do a master reset of the Control Unit, resetting it to factory defaults, clearing any erroneous operating states. See the User Guide for instructions.
The fault (Red light) goes on when the Controller is trying to rotate the antenna but not sensing the position feedback signal. Most likely the cause would be that the operating voltage is too low for the antenna size. The motor inside the rotor is designed to operate at 12 volts. Due to voltage drops in the control electronics, a 13.5 volt power supply input will provide about 12 volts to the motor. The motor speed is controlled by pules width modulation PWM and the rotation is slowed once it is within 4 degrees of the commanded heading. If the supply voltage is low and the antenna is large (like a YP-3 Yagi) then the fault most likely is due to low supply voltage, operate from a 13.5 volt power supply or fully charged battery. If the fault light goes on after the first second of a turn, then either the cable or its connections are bad or there is an internal fault.
The Rotor Unit is not designed to be left in the weather full time, it is designed for portable operations. If you are operating portable and a rain shower happens, it is recommended to not turn the Rotor until the rain stops. In normal rain fall, the mechanical seal formed by the mast and shaft provide an adequate seal. By rotating the shaft, the mechanical motion will break the surface tension of the water and allow it to more easily migrate around the water barriers and into the Rotor Unit.