Alpha SPID BIG RAK
Heavy Duty AZIMUTH ROTATOR.
The Big Rak is the biggest in a line of excellent quality rotators for serious applications. If you have a seriously 'weighty' array (such as a large EME system) then the BIG RAK is where you should be looking.
Take a look at the secification below -
Tube slide for mounting the rotor: 45-65mm Tube slide for mounting above the rotor: 45-65mm Resolution: 0.5 degrees (rotary controller can be a degree) Weight: 12kg Double worm gear Power supply: 12-24VDC Number of conductors in the rotor cable: requires at least 4 pieces Drag Torque: at 12V-24V = 583-903Nm!
All SPID rotators require an external power supply.
Typically they are run from the station 13.8v supply. For the larger rotators with sizable antennas, upto 8 amp would be required. In many cases a separate PSU from the rig is recommended, and start surge should be factored in.