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
Chapter 2—Functional Descriptions
2-58 Model 330. 340SC, and 370SC Service Manual
Table 2-11
Video Amplifier Board I/O Signals
Video Processor Board
Input
Description
VIN
COAX input from VPB via the backplane. Video signal of 1V peak-
to-peak maximum.
/ENABLE
TTL level DC signal which controls grid voltages. High causes G2
to be pulled to +15V and G1 to be pulled to -200V shutting off
the CRT beam.
CLAMP
TTL level pulse controlling DC restore. Restores black level of
cathode voltage to +84V.
BLANKING
TTL level signal controlling video blanking. Pulls G1 to 30V below
normal voltage to turn off beam.
Outputs
Description
BEAM
Positive voltage indicating beam current averaged over several lines.
1mV = 1uA of beam current.
/VIDOK
Indicates health of the +100V cathode supply. Open collector output
opens when supply goes below 64V.
CRTs
Output
Description
FOCUS
Focus voltage directly from HVPS to CRT.
GRID1
Regulated DC voltage to Grid1. Nominally -81V during normal
operation. During blanking, G1 is -111V, and during /ENABLE
high, G1 is -200V.
GRID2
Variable DC voltage to Grid2. G2 voltage is normally 800 to
1200V. When /ENABLE high, G2 is 15V.
CATHODE
DC black level modulated by video signal. DC black level is +84V.
Modulation is negative-going 75V peak-to-peak max.
FILAMENT
6.3V filtered goes to filament.
FILAMENT
RTN
Return from filament supply.
High Voltage Power Supply
Inputs
Description
-200V
Power supply to Grid1 regulator.
FOCUS
Pass-through from HVPS to CRT.
G2
+100V to +1400V supply to Grid2. Passes through G2 pulldown
circuit for protection.