Spiderbeam Rotor Adapter for Alu Masts
Spiderbeam has 3 models of Rotor Adapters in its product portfolio.
It is important that you use the correct adapter for your installation.
The bottom segment of Spiderbeam Aluminum Masts come in 2 sizes:
- 70mm
- 80mm
Common Rotors for Ham Radio antennas do not accept masts of these sizes.
- Some Rotors accept masts up to 2 in. (50mm) outer-diameter
- All common HyGain Rotors
- Some Rotors accept masts up to 63mm (~2.5 in.) outer-diameter
- Yaesu G-800, G-1000
- Some Rotors "accept" masts up to 63mm, but must not be used with masts larger than
50mm!
- Yaesu G-450, G-650
- WARNING: Using this rotor with masts larger than 50mm will cause it to rotate
out-of-round, which can eventually damage the bearings of the rotor.
- If the mast above the rotor is used with a thrust-bearing, limiting the horizontal movement of the mast, the bearings will be damaged. This includes using the rotor with a Spiderbeam Tripod.
- WARNING: Using this rotor with masts larger than 50mm will cause it to rotate
out-of-round, which can eventually damage the bearings of the rotor.
- Yaesu G-450, G-650
- If no thrust bearing is used and the mast is free to move horizontally, usually no damage will occur.
- NOTE: The latest instruction manuals specify the mast size as up to 50mm. Older versions of the manual specify up to 63mm but have a WARNING (near the back of the manual) not to use masts larger than 50mm when a thrust bearing is used.
DRILLING the 2 HOLES in
the BOTTOM OF THE MAST
The Rotor Adapter attaches to the mast with a single, long bolt.
The user must drill his/her own 2 holes on opposite sides of the mast for attaching the Rotor Adapter.
There are currently 3 different models of Rotor Adapters and several different models of aluminum masts.
Rather than specify a distance from the bottom of the mast to the position of the holes for each combination, please measure and drill holes as shown in the drawing on the right.