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
3-12 Model 330, 340SC, 370SC Service Manual
9. Cutoff R and view B.
10. Repeat Steps 2-4 for Blue.
3.8 Electronic Focus
The Electronic Focus adjustment is factory-set and should not need to be adjusted.
Whenever a major component has been replaced, like a CRT, or if the high
voltage power supply has been repaired the electronic focus will have to be
readjusted. To do this, select Test Pattern 8, H-GRID, and observe the screen for a
sharp focus at the center of the screen.
If the center appears sharply focused, there is no need to perform the electronic
focus. Follow the procedure below if readjustment is necessary.
NOTE:
The electronic focus adjustment focuses the electron beam in the CRT.
View one color at a time for these adjustments. Recheck the focus of each color
because some interaction between R, G and B may occur. The electronic focus
adjustment panel is located on the High Voltage Power Supply on the left-rear
side of the projector (refer to Figure 3-5).
To adjust the electronic focus:
1. Press T
EST
1, Test Pattern 8, H-G
RID
.
2. Cutoff R and B.
3. Continue with a low resolution source (31.5kHz/60Hz) connected to the
projector inputs and Size is at 100% from the previous CRT Mechanical
Focus procedure.
4. Using a small plastic screwdriver, adjust the electronic focus for Green
and observe the center of the screen. Have another person watch the center
of the screen up close while adjusting.
NOTE:
Be careful to adjust the E
LECTRONIC
F
OCUS
and not G2. These
adjustments are close to each other and one could be mistaken for the
other. (Figure 3-5).
5. Cutoff G and view R.
6. Repeat Step 3 for R electronic focus.
7. Cutoff R and view B.
8. Repeat Step 3 for B electronic focus.