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

Safety
viii
Model 330, 340SC, and 370SC Service Manual
WARNING!!!
High temperature, ultraviolet and infrared light. Refer
all service to factory authorized personnel.
Ultraviolet radiation, dangerous glare, and high internal gas pressure
is present at the Xenon Arc Lamp. It is contained in a protective reflector housing
module.
DO NOT operate the Xenon Arc Lamp outside its intended standard housing or outside
of the projector.
When replacement is required, the arc lamp must be replaced as an entire module as
outlined in the Hughes-JVC Model 330, 340SC and 370SC Projector Service Manual.
No attempt should ever be made to replace the arc lamp inside its module!
The arc lamp produces dangerous intense light with hazardous levels of ultraviolet and
infrared radiation. It operates at high temperatures (180ºC, maximum 300º C or over 500º
F).
Do not touch the xenon arc lamp or any connections when the lamp is ignited or is arcing.
WARNING!!!
BRIGHT LIGHT!
Never look directly at the Arc
Lamp, the lighted Projection Lens, or into the lamp housing, from any distance,
when the projector is ON and light is projected. Direct exposure to light of this
brightness can cause severe eye injury.
WARNING!!!
High voltage access and safety interlock. Defeat
restricted to factory authorized service personnel!
WARNING!!!
High voltage points up to 40,000 volts are exposed inside the covers.
Allow at least one minute to bleed off high voltage even after the unit has been turned off.
Due to high voltage danger, DO NOT TOUCH:
!
White cables to CRTs—these cables can cause severe shock from a tiny, invisible
crack or hole and should never be touched while projector power is on.
!
CRT anodes—underneath the CRTs.
!
Main power +/- supply posts—if shorted with metal objects,
!
80 amps can flow across the terminals.










