Model 335 Supplement
11
6. If none of the previous procedures cure the problem of low
brightness, it may be time to replace the Xenon Arc Lamp. Low
brightness could be caused by a lamp with over 1200 hours of use
or one that has been turned on and off many times. If either of
these is the case, the Lamphouse Assembly must be returned to
be relamped.
Do not remove the Xenon Arc Lamp from the
lamphouse
-return the entire unit.
7. Verify that the cold mirror, condensing lens, and UV filter are
all free from stains and cracks.
8. The Model 335 should always be able to achieve a minimum of
3000 lumens of brightness level. Use a light meter, after the
above adjustments are completed, to measure the foot-candles of
light output at the screen and multiply this number by the area of
the screen in square feet. As an example, if the screen area is 15
x 20 =300 square feet and the light output on the light meter
measures 11 foot-candles, the brightness level in lumens equals
300 x 11=3300 lumens.
4.0 Electronics Module Removal and Replacement
The Electronics Module is the entire assembly to the rear of the
Arc Lamp and optics assemblies. It consists of the System Power
Supply, High Voltage Power Supply, Main PCB Card Cage, and
CRT Housing Assembly. Refer to Figure 2-2 in the Series 300
Operator’s Manual (the CRT Housing Assembly is next to the
High Voltage Power Supply and is not shown in Figure 2-2).
To remove and replace the Electronics Module:
1. Unplug the projector.
2. Free the power cord from the electronics module by removing
the cable clamp(s) on the right side base of the electronics
module.
3. On the left side of the card cage, detach the power supply
jumper cable from P/J81.
4. At the rear of the projector, remove the three fan housing
screws (located under the rear lip of the projector baseplate) and
remove the fan housing. Carefully, loosen and move the attached
wires aside.
5. On the left side of the card cage, unplug connectors P82 and
P83 from the back plane and move the wiring harness out of the
way (separate these wires from others to free them if necessary).
