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C
HAPTER
3. M
AINTENANCE
P
ROCEDURES
3-127
02.9631.0010
CONFIDENTIAL
15 Jan 98
h. For model 2225 oscilloscope model only, turn HOLDOFF
knob (18) to fully counterclockwise position.
i.
Position left TRIGGER SOURCE switch (13) to CH1.
j.
Position right TRIGGER SOURCE switch (14) to LINE.
k. For model 2225 oscilloscope model only, position
COUPLING switch (19) to DC.
l.
Press in POWER button (1) to apply power. Allow unit to
warm up for 5 minutes.
m. Adjust CH1 VERTICAL POSITION knob (2) and align
trace to horizontal centerline of display to set zero voltage
reference for display.
n. Adjust HORIZONTAL POSITION knob and align trace so
that it stretches fully across width of display. For model
2225 oscilloscope, use COARSE adjustment knob (16) first,
then use FINE adjustment knob (17).
o. Position CH1 AC GND DC switch (6) to DC.
Step 11.
Attach ground clip of oscilloscope probe to luminaire chassis.
Make sure that clip is attached to unpainted surface to ensure
good ground connection. Zinc screws and most unpainted
surfaces are good places to make ground connections.
Step 12.
Using oscilloscope 10X probe, at yoke termination board,
probe green wire on four-pin MTA connector for wheel to be
calibrated:
a. Revision C Yoke Termination Board
1. W1 E.T. for color wheel 1.
2. W2 E.T. for color wheel 2.
3. GOBO E.T. for gobo wheel.
b. Revision D Yoke Termination Board
1. WH1 for color wheel 1.
2. WH2 for color wheel 2.
3. GOBO for gobo wheel.
Step 13.
At luminaire thumbwheel switch, set switch to 016 (color wheel
continuous cycle test), 017 (color wheel 2 continuous cycle
test) or 018 (gobo wheel continuous cycle test), as needed.