Project Home Rotor MicroController Motor Controller Yaesu G-5500 Software Virtual G-5500 iPoint
The Yaesu G-5500 Az-El rotator is a popular rotor for use with ham satellites. It is two independent conventional motor driven rotors one for azimuth and one for elevation. Each rotor is mechanicaly connected to a pot which provides an analog DC voltage proportional to the position of the rotor. The G-5500 control box has a connector on the back that allows complete control of the rotors through a 7 conductor cable. Four of the lines control the direction of the rotors (Up-Down for elevation and Left-Right for azimuth). Two lines are required for the analog position output (one for each motor). Include a ground line and that makes seven. Power is available from another pin on the G-5500 rotor control box but I do not recommend using this as the source of power for the controller.
Only a small number of additional parts are required to add G-5500 control to the system. A two channel A/D converter for handling the analog position information and 4 small signal NPN transistors to control the 4 rotor control lines are the only major parts required for this option.
Some people convert TV rotors for use in az-el applications. If you have a rotor system that provides a 0-5.0 volt DC analog output voltage that is proportional to position you should be able to use this system.
My wonderful Yaesu G-5500 has a maximum continuous operation time of 5 minutes (see page 2 of the manual). On page 4 of the G-5500 manual they state "The rotator motors are rated for five-minutes intermittent duty. However, they be brought to rest for at least 15 minutes after-wards". This rotor built with a stepper motor will run 24/7 without the motor having the need to rest. Stepper motors are used in CAM systems where they often run for days without stopping.
For more information on various parts of the project click on the links at the top of the page.