Projector Service Manual
Table Of Contents
- DECLARATION OF CONFORMITY
- BZSAFE.PDF
- CH1INTRO.PDF
- CH2SYSDE.PDF
- Functional Descriptions
- Contents
- Cover and Base
- External Power Requirements
- Electronics Systems Overview
- System Power
- Card Cage
- Circuit Boards
- Raster Timing Generator Board (RTG) p/n 100568
- Sync Generator
- Sync Detector and Selector
- Serration and Equalization Lockout
- Phase Locked Loop
- VSYNC Detector, Field Separator, and Mux
- Adjustment Counters
- Serial Communication
- Raster Timing Generator I/O
- Interlocks and Protection
- Horizontal Deflection Board P/N 102523 (HDB)
- Vertical Oscillator
- Horizontal Phase Locked Loop
- Horizontal Centering
- Horizontal Power Supply
- Flyback Switching
- Geometric Correction
- Output Section
- Horizontal Sweep Failure Detection
- Serial Communication
- Horizontal Deflection Board I/O
- Interlocks and Protection
- Vertical Deflection Board P/N 102521(VDB)
- Vertical Preamps
- Vertical Amplifiers
- Sweep Failure Detection
- Side Pincushion and Keystone Correction
- Horizontal Linearity Correction
- Top and Bottom Pincushion and Keystone Correction
- Correction Amplifiers
- Serial Communication
- General I/O
- Interlocks and Shutdowns
- Video Processor Board P/N 104672 (VPB)
- Decoder
- Video/Sync Mux
- V & H Sync Strip
- SG Sync Strip
- B, G, and R Brightness and Contrast Amplifiers
- On-Screen Switch
- Gamma Correction
- Switch Logic and Video Enable
- RGB Sensitivity and Threshold Amplifier
- ILA® Bias
- Dynamic Focus Amplifier
- Serial Communication
- General I/O
- Interlocks and Protection
- Video Amplifier Board P/N 103567 or 103774 (VAB)
- Video Signal
- Failure Detection
- Beam Current Sense
- DC Restore
- Arc Protection
- Blanking
- Enable Circuit
- Focus
- Filament Supply
- General I/O
- System Controller Board P/N 104668 (SCB)
- General Functional Description
- CPU
- Working and Compressed Memory
- Expanded Memory
- Correction Address Generator
- DACs
- DSP
- Overlay Memory
- Overlay Address Generator
- Overlay Interface
- LED Display Buffers and Logic
- RS232 Interface
- IR Interface
- IIC Interface
- Serial Interface
- General I/O
- Backplane Board p/n 100571
- Optical Section
- Image Light Amplifier
- Functional Descriptions
- CH3ADJST.PDF
- CH4MAINT.PDF
- Maintenance Remove/Replace)
- Contents
- Introduction
- Projector Covers
- Ventilation Filters
- Arc Lamp Assembly
- System Power Supply
- Electronics Module
- Cathode Ray Tube (CRT)
- Video Amplifier Board (VAB)
- CRT Yoke
- High Voltage Power Supply (HVPS)
- Card Cage (Printed Circuit Boards)
- Image Light Amplifier Assembly
- Projection Lens
- (SCB) Socket Battery Replacement
- Recommended Spares
- Maintenance Remove/Replace)
- CH5TRBSH.PDF
- HGLOSS.PDF
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Chapter 3---Service Adjustments
3-18 Model 330, 340SC, 370SC Service Manual
3.11 Arc Lamp Alignment and Focus
The Arc Lamp must be realigned and refocused whenever the lamp is replaced or
becomes defocused or misaligned from physical shock to the projector.
Refocusing only may be required if the Arc Lamp has been in use for a long time.
Adjustment procedures for Model 330 projectors differ from those for the Model
340SC and Model 370SC projectors and are each detailed in the following
sections.
Model 330 Arc Lamp Alignment and Focus
To check Model 330 Arc Lamp alignment, confirm the "hot spot" (brightest area)
of the screen is centered on a flat field test pattern.
If the hot spot is not centered, the Arc Lamp needs alignment.
To check if focusing is needed, use a flat field test pattern to measure the
brightness at the center of the screen and at the corners with a light meter, using
all four (4) corners to determine the roll-off. The roll-off (gradual decrease in
brightness from center to corners) should be between 2:1 and 4:1.
Do not
try to
compensate for a dim corner by adjusting the Arc Lamp—dimness in one or two
corners is usually caused by variations in the
ILA
®
assemblies and will be
corrected by Shading adjustments. Perform the Arc Lamp focusing procedure
only if
the roll-off in all four (4) corners is too high.
CAUTION!
In the interest of safety, please read
these entire procedures,
prior to performing any adjustments
, in
order to become familiar with the special
NOTES
and
CAUTIONS
indicated.
To align the Model 330 Arc Lamp (refer to Photo 3-2):
1. Use a long-handled Hexhead tool (a long handle helps keep fingers away
from Ignitor terminals) to loosen the four (4) Arc Lamp holding screws
very slightly, just so that the washers under the screwheads become loose
enough to move on the shaft.
CAUTION!
Be careful to not touch the Arc Lamp—it
is very hot! Be especially careful when loosening the bottom screw
so that the shaft of the Hex tool does not touch the Ignitor terminals
to the right of the tool.
2. Insert 2 Allen wrenches in the X and Y adjustment screws.
3. Turn the Allen wrenches in or out to center the hot spot on the screen.