Checking the Control Unit Voltages
To check the control unit voltages, first remove
the rotator control cable from the DCU-1 control
box, then plug the line cord into a 110 VAC
outlet. Set the target bearing at least 10 degrees
from the current bearing. Press "START" to
check voltages on pins 2, 5, and 6. Check for the
following voltages on the 8 pin connector:
NOTE:
You have 8 seconds after pressing "START" to
make each measurement. The DCU-1 checks for
movement, and after 8 seconds without
movement, it stops trying to rotate. You may
wish to make your meter connections with
alligator clips, then press "START" when you
are ready to read the meter.
Pin #'s
Ambient State
Press "START" (see note)
1-2
0
30 VAC
1-5
0
30 VA C (for CW rotation to target)
1-6
0
30 VA C (for CCW rotation to
target)
4-8
0
0
3-7
+ 5.0 VDC
+ 5.0 VDC
Table 4
Checking the Rotator Resistances
from the ground
You may possibly avoid bringing the rotator
down from the tower by making electrical
resistance checks on the control cable.
Disconnect the control cable from the control
box. Check for the following resistances:
Description
Pin #'s
Approximate Resistance (ohms)
Brake Solenoid
1-2
0.75 + cable resistance
1/2 Motor Winding
1-8
2.5 +cable resistance
1/2 Motor Winding
1-4
2.5 +cable resistance
1/2 Motor W switch
1-6
2.5 +cable resistance
Entire Motor
4-8
4.5 + cable resistance
Right Limit Switch
5-8
0 +cable resistance
Left Limit Switch
4-6
0 + cable resistance
Entire Pot
3-7
500 + cable resistance
Pot Arm to + End
1 - 3
0 to 500 ( 0 at full CCW)
Pot Arm to - End
1-7
0 to 500 ( 500 at full CCW)
Table 5
