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 2—Functional Descriptions
2-54 Model 330. 340SC, and 370SC Service Manual
high resulting in shutdown of grid bias at the Video Amplifier Boards. Also,
the SWEEPOK status bit will be transmitted as a low to the SCB.
/GVIDOK
Similar to /RVIDOK.
/BVIDOK
Similar to /RVIDOK.
Output
/HVEN
When either /RVIDOK, /GVIDOK, or /BVIDOK from the Video Amplifier
Boards is pulled high, or the +5V power on the Video Processor Board goes
low, /HVEN is pulled high. This results in the HVPS being disabled, thus
shutting down high voltage to the CRTs.
/RENABLE
High will cause grid voltages at the VAB to be pulled low shutting off the red
CRT beam. High will result from high on /RVIDOK, /GVIDOK, or /BVIDOK
from the VAB, +5V power going down on the VPB, or /SWEEPOK being
pulled high from the VDB.
/GENABLE
Similar to /RENABLE.
/BENABLE
Similar to /RENABLE.
Internal
None
Video Amplifier Board P/N 103567 or 103774 (VAB)
The Video Amplifier Board (VAB) is mounted on and plugs into the back of the
CRT. There are three (3) VABs—one (1) on each CRT and each is entirely
dedicated to servicing its respective CRT. The video amplifier boards are the last
stage of the video chain and provide all electrical connection to the CRTs except
for anode voltage and chassis bond.
The following functions are provided by the VPB:
Connection of all voltages to CRT.
Amplification of video signal.
Blanking.
DC restore.
Bias voltage control.