JVC 340 SC, 370 SC, 330 User Manual
SERVICE
MANUAL
Model 330
Model 340 SC
Model 370 SC
Hughes-JVC Technology Corporation
2310 Camino Vida Roble, Carlsbad, CA 92009-1504
☎
760-929-5300
DECLARATION OF CONFORMITY
760-929-5410
AX
F
service@hjt.com
e
✉
-
PER ISO/IEC GUIDE 22 AND EN 45014
Manufacturer: Hughes-JVC Technology Corporation
2310 Camino Vida Roble
Carlsbad, CA 92009-1504
USA
Hughes-JVC declares that this product conforms to the following
Product Specifications (Directive/Standard):
Safety: EN 60950
IEC 950 (1992)
EMC: EN 55022 (1988) / CISPR-22 (1986) Class "A"
EN 50082-1 (1992) / IEC 801-2 (1991)
EN 50082-1 (1992) / IEC 801-3 (1984)
EN 50082-1 (1992) / IEC 801-4 (1988)
ANSI C63.4-1992, FCC, Part 15, Class A
In addition, the above product complies with the requirements of the
Low Voltage Directive 73/23 EEC and the EMC Directive 89/336/EEC.
105662 First Edition January 1998
Rev A September 1998
Hughes-JVC Technology Corporation
is ISO 9001 Registered and Certified.
Confidential and proprietary information.
© Copyright 1998 by Hughes-JVC Technology Corporation.
All worldwide rights reserved.
This manual was produced by Hughes-JVC Technology Corporation
and may be revised without prior notice.
No part of this manual may be reproduced in any form without
the express written permission of Hughes-JVC Technology Corporation.
®
is a registered trademark of Hughes-JVC Technology Corporation.
ILA
iii
Model 330, 340SC and 370SC Service Manual
Safety Information
Introduction
Before operating or working on a Model 330, 340SC and 370SC Projector, especially
with the cover off, please read this safety information section thoroughly. Procedures
requiring the opening of the projector covers and/or contact with electrical components
should be performed by qualified service personnel. Strictly adhere to all notes and
warnings.
Safety Equipment
Safety equipment specified in the Hughes-JVC Series 300 Projector Service and
Operator’s Training Course and certification program or equivalent should be used for
maintenance of the equipment.
Safety
Warnings and Cautions
Warnings and Cautions
Warnings and Cautions in this manual should be read thoroughly and strictly adhered to.
Warning and Caution symbols and definitions are as follows:
WARNING!!!
and/or specific procedure or situation that could result in personal injury if
improperly performed.
CAUTION!
hazards that could cause severe eye injury or a specific procedure or situation
that could result in damage to the equipment if improperly used.
The following important safety instructions are designed to insure your safety and the
long life of your projector. Be sure to read these safety instructions thoroughly and adhere
to all warnings given below.
Warns user of a potential safety hazard or potential light
Warns user of a potential electric shock hazard
This device complies with Part 15 of the FCC Rules. Operation is subject to the following
two conditions: (1) this device may not cause harmful interference and (2) this device
Model 330, 340SC, and 370SC Service Manual v
Safety
must accept any interference received including interference that may cause undesired
operation.
Operation of this equipment in a residential area is likely to cause harmful interference, in
which case the user will be required to correct the interference at their own expense.
Shielded interconnect cables must be used with this equipment to insure compliance with
the pertinent RF emission limits governing this device.
Installation Safeguards
WARNING!!!
power on the projector until the damaged cable is replaced.
not
CAUTION!
If there is any visible damage to any of the cables
Place the projector on a smooth, stable and level surface
do
in an area free from dust and moisture. Do not place the equipment in direct
sunlight or near heat-radiating appliances. Smoke, steam and exposure to direct
sunlight could adversely affect the internal components. Avoid rough handling
when moving your equipment, as a strong shock could damage its internal
components.
CAUTION!
If installing a ceiling mount, use only parts supplied or
recommended by the manufacturer. Observe all instructions and warnings as
listed in this manual.
Projector Weight
The HJT projector and shipping container have a combined weight of either 512 (Model
330 and 340SC) or 550 (Model 370SC) pounds. The HJT shipping container weighs 170
pounds and the projector itself weighs either 342 (Model 330 and 340SC) or 380 (Model
370SC) pounds.
Do Not Tilt the Projector More Than 85 Degrees
Do not mount the projector on an excessively tilted base. The projector can be tilted a
maximum of 85 degrees. Mount it only on a stable, vibration-resistant base capable of
supporting at least three times its weight. If in doubt, contact the factory.
vi
Model 330, 340SC, and 370SC Service Manual
Safety
Avoid Projector Angles of 15° to 23°
Due to voids in the prism fluid there is a dead zone of 19° ± 4°. For this reason, avoid
projector angles of 15° to 23°.
Maximum Projector to Screen Angle is 15°
The maximum vertical tilt angle from projector to screen is 15°. This is the maximum
amount of keystone correction that is possible.
Heat Safeguards
Fans
The projector has multiple fans (exact number varies with projector model number) to
cool the projector system. Do not block the intake or outflow of any of the fans.
Intense heat is emitted within the system and must be properly dissipated in order to keep
the system running properly.
CAUTION!
ports can lead to projector overheating. Do not enclose the unit in a restricted
space. Refer to the appropriate
thermal clearance and for specific clearances needed for heat dissipation. Allow
at least ten (10) minutes for projector cool down before removing power.
has stopped running. This fan protects the arc lamp from overheating.
CAUTION!
Light Safeguards
Ultra Violet and Infrared Li ght
Eye/face protection is required from ultra violet light and infrared light in accordance
with the following conditions:
1. X3 (up to 375 nanometers) shade goggles must be worn by anyone near the
projector when the lamp is lit and the cover is off.
2. X5 (375 to 700 nanometers) shade goggles when actually working on the
projector near the arc lamp source.
Do Not Block Ventilation. Blocking air intake or exhaust
Operator’s Manual
Do not unplug the power cord until after the arc lamp fan
for physical access and
vii
Model 330, 340SC, and 370SC Service Manual
Safety
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.
viii
WARNING!!!
High voltage access and safety interlock. Defeat
restricted to factory authorized service personnel!
WARNING!!!
Allow at least one minute to bleed off high voltage even after the unit has been turned off.
High voltage points up to 40,000 volts are exposed inside the covers.
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.
Model 330, 340SC, and 370SC Service Manual
Safety
!
CRT yoke assemblies and other proximity electrical assemblies, components and
wiring—if performing the yoke rotation or width adjustment (outlined in Section
3.2), always use an
!
ANSI/ASTM 10,000 volt rated safety glove.
!
Periodically check the condition of safety gloves for cracks.
!
Arc Lamp main power ± posts.
Power Supply
The projectors operate from power sources indicated in the table below. Verify that local
power source matches these requirements before operation!
Projector Power Supplies
Power
AC
Current
Hz
Watts
330
200-240V
20
50-60
2,700
340SC
200-240V
20
50-60
3,325
370SC
200-240V
30
50-60
4,550
Handle the power cord carefully and avoid excessive bending.
A damaged cord may cause electric shock or fire. For continued safe and reliable
operation, only use cables supplied by the manufacturer for power and signal connections.
Installation should be performed by an electrician with current knowledge of electrical
codes in the country of use.
Fluid Safeguards
Certain components of the projector contain fluid. If any fluid from the projector contacts
the skin, wash off with soap and water. If any fluid from the projector splashes into the
eyes, rinse with cool running water.
Ventilation and Foreign Object Retrieval
Ensure the projector’s multiple fans are free from obstructions and operating properly.
Air filters are located at vent ports on the cover. Air filters require periodic cleaning to
ensure adequate cooling of the projector (see Section 4.3). Verify that vent ports are clear
of all obstructions.
Keep the projector free from foreign objects, such as hairpins, nails, paper, etc. Do not
attempt to retrieve such objects yourself or insert metal objects such as wire and
screwdrivers inside the unit. If an object falls inside the projector, unplug the projector
immediately and call a Hughes-JVC certified technician for removal.
ix
Model 330, 340SC, and 370SC Service Manual
Safety
WARNING!!!
Various procedures in this manual involve the removal
and replacement of system subassemblies. Ensure that the projector AC power
plug is removed from the AC outlet
to attempting any of these procedures.
prior
x
Model 330, 340SC, and 370SC Service Manual
Safety
xi
Model 330, 340SC, and 370SC Service Manual
1.0 Introduction
This Model 330, 340SC and 370SC Service Manual combines three (3) similar
projector models into one (1) reference book, and should be used in conjunction
with the appropriate projector Operator’s Manual. This manual provides more
detailed information on troubleshooting and maintaining the projectors and a more
in-depth functional description of the system subassemblies than the specific
Operator’s Manual, which cover the specific projector system description,
installation, adjustments, operation, maintenance, specifications, troubleshooting
guide, and parts list.
The areas covered in this Service Manual include any similarities and differences
of functional descriptions of Model 330, 340SC and 370SC projector electronics,
service adjustments, maintenance (removal and replacement of subassemblies),
and troubleshooting.
Chapter 1---Introduction
1.1 Acronyms Used In Manual
ALPS Arc Lamp Power Supply
CH Channel
CPU Central Processing Unit
CRT Cathode Ray Tube
DSP Digital Signal Processor
EPROM Erasable Programmable Read-Only Memory
F to V Frequency to Voltage
G2 CRT Grid 2
HDB Horizontal Deflection Board
HDTV High Definition Television
HSYNC Horizontal Sync
HVPS High Voltage Power Supply
ILA® Image Light Amplifier
I/O Input/Output
I/R Infrared
kHz Kilohertz
LED Light Emitting Diode
LVPS Low Voltage Power Supply
NTSC National Television Standards Committee
PCB Printed Circuit Board
PLL Phase Lock Loop
PLUGE Picture Line-Up Generating Equipment
RAM Random Access Memory
RGB Red, Green and Blue
ROM Read Only Memory
Model 330, 340SC and 370SC Service Manual 1-1
Chapter 1---Introduction
RTG Raster Timing Generator
SCB System Control Board
SPS System Power Supply
TTL Transistor-Transistor Logic
VAB Video Amplifier Board
VCO Voltage Controlled Oscillator
VDB Vertical Deflection Board
VIN Video Input
VPB Video Processor PCB
VSYNC Vertical Sync
VTR Video Tape Recorder
1.2 Safety
High voltages and high intensity light sources exist in the Model 330, 340SC and
370SC Projector Systems and power supplies. Prior to performing any procedures,
adjustments or maintenance review the chapter on Safety Information at the front
of this manual.
1.3 Updates
This manual will be updated with information provided by Service Bulletins and
manual supplements whenever necessary.
1.4 Hardware Compatibility
The table below lists part numbers currently compatible between the Model 330,
340SC and 370SC projectors, and those parts that are different in each.
Table 1-1
Printed Circuit Boards
DIFFERENT
Lamp Assembly
Ignitor
System Power Supply
High Voltage Power Supply
SAME
Hardware Compatibility
330
900611S
102083
104070
100562
340SC
PART NUMBERS
104651
102207
104071
100562
370SC
104120
104475
104038
103769
1-2
Raster Timing Generator
Horizontal Deflection Board
Vertical Deflection Board
Video Processing Board
100568
102523
102521
104672
Model 330, 340SC and 370SC Service Manual
100568
102523
102521
104672
100568
102523
102521
104672
Chapter 1---Introduction
Printed Circuit Boards
Video Amplifier Board
System Controller Board
Table 1-2
Different
3,000 lumens
2,500 ANSI lumens
220V AC, 20A, 60Hz
2,700 Watts power
1,500 W Xenon arc lamp 2,000 W Xenon arc lamp 3,000 W Xenon arc lamp
Same
5.2.1 software
graphics enhancement
Projector Model Comparisons
330 Model
4,200 lumens
3,700 ANSI lumens
220V AC, 20A, 60Hz
3,325 Watts power
5.2.1 software
graphics enhancement
340SC Model
330
103774
104668
340SC
103774
104668
6,800 lumens
6,000 ANSI lumens
220V AC, 30A, 60Hz
4,550 Watts power
5.2.1 software
graphics enhancement
370SC
103774
104668
370SC Model
30 memories
decoder board option
30 memories
decoder board option
30 memories
decoder board option
Model 330, 340SC and 370SC Service Manual 1-3
Chapter 2—Functional Descriptions
2.0 Functional Descriptions
Contents
2.1 Cover and Base............................................................................................2–2
2.2 External Power Requirements.....................................................................2–3
2.3 Electronics Systems Overview....................................................................2–3
2.4 System Power..............................................................................................2–5
System Power Supply................................................................................2–5
Arc Lamp Ignitor.......................................................................................2–9
High Voltage Power Supply......................................................................2-11
2.5 Card Cage....................................................................................................2-14
2.6 Circuit Boards .............................................................................................2-15
Raster Timing Generator Board (RTG) p/n 100568 ................................2-18
Horizontal Deflection Board P/N 102523 (HDB).....................................2-25
Vertical Deflection Board P/N 102521(VDB)..........................................2-32
Video Processor Board P/N 104672 (VPB)..............................................2-43
Video Amplifier Board P/N 103567 or 103774 (VAB)............................2-54
System Controller Board P/N 104668 (SCB)............................................2-59
Backplane Board p/n 100571...................................................................2-71
2.7 Optical Section............................................................................................2-72
CRT Assembly..........................................................................................2-72
Arc Lamp Assembly..................................................................................2-75
Optical Subassemblies...............................................................................2-76
2.8 Image Light Amplifier.................................................................................2-76
This chapter provides functional descriptions of the major assemblies in the
Model 330, 340SC and 370SC projectors.
Emphasis is placed on a description of system components to the functional block
level. A number of block diagrams are provided for user reference.
Figure 2-1 provides a block diagram overview of the HJT Model 330, 340SC and
370SC projectors. For simplicity, each major electronics assembly is shown with
signal paths between appropriate functional units. Major physical and electronics
assemblies will be described in more detail in the following sections of this
chapter.
Model 330, 340SC and 370SC Service Manual 2–1
Chapter 2—Functional Descriptions
Low Voltage
Power Supply
Lamp Ignitor
System
Controller
Line Voltag e
RS 232
Infrared Remote
System
Power
Supply
Arc Lamp
Horizontal
Deflection
Channel 1
Channel 2
(R,G,B, H/V Sync)
Video
Processor
Figure 2-1
Model 330, 340SC and 370SC System Block Diagrams
2.1 Cover and Base
and 370SC projectors must be installed for proper operation.
Operation of the projector, other than for maintenance, with the
covers removed is not recommended and will void the projector
warranty.
CAUTION!
Video Output
Amplifier
Raster
Timing
Generator
The covers for the HJT Model 330, 340SC
Vertical
Deflection
and
Convergence
High Voltage
Power Supply
Fans
Image Light
Amplifiers
(3 each
CRTs
(3 each)
In addition to aesthetics, the covers on the Model 330, 340SC and 370SC
projectors serve several functions. The covers are an integral part of the cooling
system of the projector. Air intake filters are contained in the covers as are cooling
fans. The covers provide the operator and audience with protection from the
extremely bright light produced in the projector. The covers also serve to reduce
the noise generated by operation of the projector. The UL approval is only valid
with the covers installed since they provide the primary protection to prevent
personnel from coming into contact with the high voltages and currents contained
within the projector.
2–2 Model 330, 340SC, and 370SC Service Manual
The HJT Model 330, 340SC and 370SC
WARNING!!!
projectors use high voltages and high currents. Operation with
covers removed exposes personnel to these dangerous conditions
and may result in serious injury or death. No user-serviceable parts
are contained within the projector. Refer all maintenance to only
factory authorized and trained technicians.
The projector cover is a two-piece molded assembly. It is fastened to the projector
frame by six (6) screws: two (2) on the rear cover; and four (4) on the front cover.
The fan intake side of the cover (right side) has filters on the intake vents.
Periodic cleaning of the filters is required and should be performed in accordance
with the procedure in this manual (Section 4.3). To avoid overheating the
projector, ensure that the cover vent ports are free of obstructions at all times and
that an adequate supply of fresh air is provided to the projector during operation.
2.2 External Power Requirements
Chapter 2—Functional Descriptions
The projectors require 208V to 240V, 50 Hz to 60 Hz, single-phase AC power.
The units are equipped with an attached AC power cord and 3-prong twist lock
plug (Model 330 and 340SC use Hubble Model 2323; Model 370SC uses Hubble
Model 2623 or equivalent).
CAUTION!
Operation at voltages and frequencies outside of these
listed parameters may cause damage to the projector and will void the warranty.
2.3 Electronics Systems Overview
The objective of this portion is to provide a good general understanding of the
projector electronics. The understanding gained will enable service personnel to
more effectively maintain the projector to produce the desired result—a great
picture on the screen —and quality you can see.
The Electronics Systems portion of this manual is based on block diagrams. The
diagrams used have been drawn with two purposes in mind. First, they are general
enough to be able to gain an understanding of the overall function of the various
components of the system. Second, the block diagrams contain enough detail to
make them valuable as a troubleshooting tool should the need arise. Schematics
are not used but, where necessary, simplified circuitry is shown to aid in
understanding the capabilities and/or limitations of the system. Discussion of
troubleshooting is included but is largely confined to symptoms and identification
of failed assemblies.
The Hughes-JVC Model 330, 340SC and 370SC projectors are multi-sync
projectors capable of data, graphics, and display from 15KHz to 90KHz
Model 330, 340SC and 370SC Service Manual 2–3
Chapter 2—Functional Descriptions
horizontal and 45Hz to 120Hz vertical. The projected image is continuously
variable from 6 ft to 60 ft over throw distances (varies by projector model) from
10 ft to over 360 ft. All HJT Series 300 projectors are capable of keystone,
pincushion, and linearity correction. The projectors feature digital control of
functions, including convergence, picture adjustments, switching and diagnostics.
In addition, the projector provides the ability to control the relative brightness
anywhere on the screen.
The capabilities of the Model 330, 340SC and 370SC projectors are provided by a
sophisticated electronics system, which consists of power supplies, input/output
devices, and various circuit boards, and using both analog and digital components
to provide functionality with a simple user interface. The electronics systems are
assembled in modular fashion for ease of removal or maintenance.
The Model 330, 340SC and 370SC Electronics System consists of:
System Controller Board;
Video Processor Board;
Video Amplifier Boards (3);
Raster Timing Generator Board;
Horizontal Deflection Board;
Vertical Deflection Board;
Lamp Ignitor;
System Power Supply;
High Voltage Power Supply.
There are also image and sync signal inputs, an LED display, two (2) RS-232
communication ports, and two (2) IR receivers for projector control.
The digital and analog circuits of the System Controller Board direct the operation
of image and raster generation circuits as well as controlling the input/output and
power supply operation of the HJT Model 330, 340SC and 370SC projector
electronics systems.
The System Controller sets operating parameters of the system such as brightness
and contrast, produces internal test patterns and generates on-screen overlays, and
sets the timing for the raster generation to adjust phase, geometric corrections,
uniformity corrections and convergence. The System Controller houses the
program memory as well as the memory for all convergence and uniformity maps,
and has the responsibility of controlling communication with the user, power to
the other areas of the projector, and other necessary functions.
The Video Processor and Video Amplifiers select the desired input signal and
process it to produce the CRT beam modulation necessary to produce an image on
the raster.
2–4 Model 330, 340SC, and 370SC Service Manual
Chapter 2—Functional Descriptions
The Raster Timing Generator provides timing signals to the System Controller
Board, selects the appropriate incoming sync signal and produces the timing
signals for controlling the geometry of the raster.
The Vertical and Horizontal Deflection Boards produce their respective sweep
currents to drive the deflection yokes. The Vertical Deflection Board also houses
the convergence amplifiers that drive correction coils.
The System Power Supply provides all DC power below 200V to the projector.
This includes the supply to the arc lamp/ignitor and the supply to the High
Voltage Power Supply.
The High Voltage Power Supply provides all voltages of 200V and higher. This
includes all CRT bias voltages except the cathode.
Image and sync inputs arrive in the projector at the Video Processor Board.
Inclusion of the Decoder Board is optional. User communication is accomplished
by on-screen displays, LED display output, IR remote input, or RS232
Input/Output. All of these devices are separate from, but communicate directly
with the System Controller Board.
The detailed functional description of the subassemblies are covered below in the
following order:
1. System Power.
2. Card Cage and Circuit Boards.
3. CRT Assembly.
4. Arc Lamp.
2.4 System Power
System Power Supply
The System Power Supply provides the connection between the external power
source and the projector. The System Power Supply provides all internal DC
power to the projector with the exception of that provided by the High Voltage
Power Supply (Section 2.4.3). This includes the low voltage power to the
electronics, the supply power to the HVPS, and the Arc Lamp power.
The System Power Supply is a AC-DC power supply with an input rectifier and
protection circuit and several separate switchers; one (1) for Arc Lamp power, one
(1) for +5V Standby power, one (1) for +24V Standby power, and others for the
other low voltages.
All of the power supply outputs are protected against overvoltage and overcurrent.
Overcurrent protection is a foldback circuit that limits the output current by
reducing the output voltage when an overcurrent condition is detected. An
overvoltage condition at the output of the supply will cause the affected voltage to
be shut down until input power is removed and reapplied.
Model 330, 340SC and 370SC Service Manual 2–5
Chapter 2—Functional Descriptions
All of the SPS output voltages except Arc Lamp power are indicated by a LED
display (see ). The LEDs are located on a bar-type display on the backplane at the
left side of the card cage. The individual LEDs will be lit when the corresponding
voltage is energized. The LEDs are wired to the SPS output power using only a
current limiting resistor so when the LED is lit, it is an indication that there is a
voltage present, not necessarily the correct voltage. To verify whether or not the
voltage at the output is correct, a voltmeter must be used to probe the output
connectors J500, J501, or J502.
+5V +5V
STB
Figure 2-2
A safety interlock switch is located on top of the power supply. The interlock
+24V
STB
+6.3V +15V -15V +24V +48V+107V -200V
Backplane Status Indicators.
switch shuts off the System Power Supply whenever the cover is removed. During
normal operation with the cover installed, the switch is in the 'armed' position.
When the rear cover is removed, the switch will be released and cause power to
the projector to be interrupted. To run the unit without the cover installed,
override the interlock switch by pulling it up into the 'service' position. When the
cover is replaced, the switch will automatically be reset into the 'armed' position.
A circuit breaker is located on the right side of the System Power Supply. The
circuit breaker serves to remove all power from the projector (except for the
power at the input terminals) by switching it to the OFF position.
CAUTION!
The circuit breaker must be switched off, and the
projector must be disconnected from AC power prior to performance of any
maintenance, to ensure that all power is removed from the internal components of
the projector.
Normal operation of the System Power Supply is as follows:
When external power is applied, +5V Standby will always be energized as will the
internal SPS fans. +24V Standby power for operating the fans will be energized
whenever the lamp or electronics are turned-on and five (5) minutes after the
projector is shut down.
All other voltages are controlled by the power-up or power-down commands
issued by the operator.
2–6 Model 330, 340SC, and 370SC Service Manual
Chapter 2—Functional Descriptions
The Arc Lamp power supply is a current-controlled supply with an open circuit
voltage of about 170V. When the Arc Lamp is operating at steady state, the power
supply provides the current set by the technician. The output of the supply has a
large capacitor that will, on initial ignition of the Arc Lamp, provide the very high
initial current necessary to ionize the xenon gas in the lamp and sustain the arc.
The current setpoint is initially set at the factory and must be reset by the
technician whenever an Arc Lamp is replaced.
AC INPUT
220-240vac
50Hz
From
System
Controller
POWER
FACTOR
CORRECTION
/FANENBL
J502
Model 330. Model 340SC = +25V/80a; Model 370SC = +30V/100a.
∇
/LVPSNBL
/ALENBL
Figure 2-3
System Power Supply Block Diagram.
STANDBY/
I/O CONTROL
+5v, +24v
LOW VOLTAGE
Power Supply
+5v,+6.3v,+-15v,
+24v,+48v,+107v
ARC LAMP
Power Supply
and Boost
+22v/68a
+170v/1.0a
∇
J502
J500
J503 (-)
J504 (+)
To
Backplane
To
Arc Lamp
Via
Ignitor
Normal system power-up (Electronics and Lamp):
1. Upon receipt of Power-On command, SCB pulls /FANENBL and
/ALENBL lines low.
2. +24V Standby and Arc Lamp power supplies turn on.
3. When Arc Lamp lights (run voltage sensed by a window comparator in the
SPS), SPS pulls /LAMPLIT line low.
4. When SCB senses /LAMPLIT low, SCB pulls /LVPSNBL line low.
5. Low voltage supplies turn on.
6. SCB senses +5V supply at correct level and enters normal program
sequence.
Lamp only power-up:
1. Upon receipt of Lamp-On command, SCB pulls /FANENBL and
/ALENBL lines low.
Model 330, 340SC and 370SC Service Manual 2–7
Chapter 2—Functional Descriptions
2. +24V Standby and Arc Lamp power supplies turn on.
3. When Arc Lamp lights (run voltage sensed by a window comparator in the
SPS), SPS pulls /LAMPLIT line low.
4. SCB senses /LAMPLIT low and awaits further instructions.
Electronics only power-up:
1. Upon receipt of Electronics-On command, SCB pulls /FANENBL and
/LVPSNBL lines low.
2. +24V Standby and Low voltage supplies turn on.
3. SCB senses +5V supply at correct level and enters normal program
sequence, lamp can be turned on at any time.
Table 2-1
VoltageFa
+5v
+5v Stb
+6.3v
+15v
-15v
+24v
+24v Stb
+48v
+107v
+170v
System Power Supply Voltage Distribution
HV
PS
n
CRT SCB HDB VDB VPB RTG VAB
Arc
Lamp/
Ignitor
2–8 Model 330, 340SC, and 370SC Service Manual
Chapter 2—Functional Descriptions
*Current depends on projector model (see Table 0-1 in Safety Chapter).
** Model 340SC = 2000 Watts; Model 370SC = 3000 Watts.
Figure 2-4
System Power Supply Input/Output Diagram
Arc Lamp Ignitor
The ignitor consists of a step-up power supply, a spark gap, and a transformer.
The Arc Lamp Ignitor is mounted under or next to the Arc Lamp. It provides the
high voltage pulse necessary to ignite the Xenon Arc Lamp that is the illumination
supply for the HJT Model 330, 340SC and 370SC projectors.
The System Power Supply’s Arc Lamp Supply section provides the necessary
voltage to activate the ignitor and to sustain the arc in the Arc Lamp once it has
been ignited. The SPS provides the power necessary to operate the ignitor.
The Ignitor is only active during the time between the Arc Lamp Power Supply
energizing and the Arc Lamp igniting. During steady state operation and when the
projector power is off, the ignitor is inactive.
Model 330, 340SC and 370SC Service Manual 2–9
Chapter 2—Functional Descriptions
When the Arc Lamp supply first turns on, it supplies 170V to the ignitor. The
ignitor then senses this voltage, activates it’s on-board supply, and produces a
1µS, 38KV pulse to the Arc Lamp. This pulse strikes an arc in the lamp. The Arc
Lamp supply then provides the high current necessary to sustain the arc in the
lamp. Refer to Figure 2-5 and the summary below for a description on the Arc
Lamp and Ignitor timing.
/FANENBL
/ALENBL
/LAMPLIT
38 KV
170V
22-30V
*
0V
1
2
3
4
5
6
ARC LAMP ON
IGNITOR FIRES
CPU TIME-OUT
5-10 MINUTES
LAMP-OFF
COMMAND
FAN DISABLE
LAMP-ON COMM A ND
*
22-30V depending on projector model.
Figure 2-5
Arc Lamp/Ignitor Timing Diagram Summary:
Arc Lamp Ignitor Timing Diagram
1. The operator powers Arc Lamp on. /ALENBL and /FANENBL from
System Controller Board are pulled low. SPS receives /ALENBL from
SCB and turns on the Arc Lamp PS.
2. Ignitor receives +170V boost voltage from the Arc Lamp PS.
3. Ignitor steps up the +170V boost voltage to a 1 µsec pulse, approximately
38KV.
4. Arc Lamp ignites from the 38kV pulse.
5. High current (about 68-100A depending on projector model) begins
through Arc Lamp and voltage drops to +22-30V (depending on projector
model).
6. /LAMPLIT signal goes to SCB to inform board that Arc Lamp is lit.
2-10 Model 330, 340SC, and 370SC Service Manual
Chapter 2—Functional Descriptions
High Voltage Powe r Supply
The High Voltage Power Supply is a DC-DC converter (see Figures 2-6 and 2-7)
and is located on the left side of the CRT housing. It provides all necessary
voltages for the CRTs except the cathode drive, which comes from +107V from
the SPS.
Figure 2-6
Input power is +24V at 5A from the SPS. The input power is converted into the
High Voltage Power Supply
high voltage necessary to bias the CRTs.
The HVPS is controlled by an enable line (/HVEN) originating at the Video
Processor Board. This enable line is controlled by logic that turns the HVPS off
when there is a fault that could damage the CRTs. There are two (2) different
conditions that could damage the HVPS:
1. If the +5V supply to the VPB is interrupted, the control and protection is
compromised and the HVPS must be turned off.
2. If the cathode drive power is lost on one of the Video Amplifiers, the
cathode current cannot be controlled and the HVPS is turned off.
3. Further details regarding this logic can be found in the functional
description on the Video Processor Board in Section 2.6.4.
Model 330, 340SC and 370SC Service Model 2-11
Chapter 2—Functional Descriptions
The HVPS provides several voltages to the CRTs:
Anode
Grid 1
Grid 2
Focus
+24v
GROUND
HDFOCUS
HDFOCUS RTN 8
VDFOCUS
/HVEN
Figure 2-7
2
3
11
High
Voltage
12
9VDFOCUS RTN
7
Power and Control Connector
Power
Supply
6
(Pins 1,4,5,10 not used)
RED ANODE
GREEN ANODE
BLUE ANODE
RED FOCUS
GREEN FOCUS
BLUE FOCUS
RED G2
GREEN G2
BLUE G2
-200v
High Voltage Power Supply Input/Output Diagram
12369
11258
10147
Figure 2-8
2-12 Model 330, 340SC, and 370SC Service Manual
HVPS Power and Control Connector Jack, J603
Chapter 2—Functional Descriptions
CRT anode voltages are not user controllable. They are fixed at 32KV with a
maximum output of 2.1mA total or 0.7mA per CRT. The anode voltage is the
primary acceleration voltage for the CRT. Other bias voltages (screen grid, G2,
and control grid, G1) are used to control the level of beam current. The anode
voltage is routed out of the top of the HVPS, into the CRT housing to three (3)
bulkhead connectors. From there, the anode wires on the CRTs route the anode
voltage directly to the CRT. The anode voltages are overvoltage and overcurrent
protected in the event of short circuits or CRT arcing.
Focus voltage (called Electronic Focus) is a modulated DC voltage. The DC level
is set by the user during initial setup to focus the CRT electron beam. The
Electronic Focus controls are located on the left side of the HVPS (see appropriate
model Operator’s Manual). There are three (one for each color) ¾ turn pots for
adjusting the Electronic Focus. Of the six (6) pots found on the HVPS, the bottom
three (3) are for focus while the top three (3) are for G2 adjustment (Section 3.10).
The DC voltage is modulated within the HVPS using the HDFOCUS and
VDFOCUS input signals. VDFOCUS is the vertical dynamic focus signal, which
is a waveform with parabolic shape at the vertical sweep frequency. HDFOCUS is
the horizontal dynamic focus signal. It is a combination of the vertical dynamic
focus signal and a parabolic waveform at the horizontal sweep rate. These two (2)
signals are combined in the HVPS to form a composite dynamic focus signal.
Dynamic focus is necessary to ensure that the CRT electron beam is converged to
a point as the beam sweeps across the CRT face. Since the CRT faceplate is flat,
the raster sweep causes a varying path length for the electron beam. This means
the focus voltage must be varied as the raster is traced. Focus voltage cannot be
conveniently measured during normal operation.
G2 screen grid voltage is a DC voltage that is set by the user. The three (3)
adjustment controls, one for each color, consist of ¾ turn pots and are located on
the left side of the HVPS immediately above the focus controls. This voltage is set
during initial projector setup to adjust the black level on the screen (see
appropriate model Operator’s Manual). The G2 voltage sets the bias on the screen
grid of the CRT and is normally used to set the cutoff level. However, since the
HJT light valve requires a non-zero input to produce a just-cut-off image on the
screen, G2 is set to produce a slightly greater-than-black raster on the CRT. The
G2 is adjustable from 100V to 1400V individually by color. The actual operating
level will be near 1200V. G2 voltage cannot be conveniently measured during
normal operation.
-200V is the supply to the control grid (G1) of the CRTs through the Video
Amplifier Board. This voltage is not user controllable. The -200V is the only
output voltage from the HVPS that goes to the backplane of the projector to be
routed to the Video Amplifier, and uses the rear-most LED of the backplane LED
bar for indication.
-200V is the only convenient means of directly observing whether or not the
HVPS is turned on, either by observing the indicator LED on the backplane, or by
probing the control connector with a voltmeter.
Model 330, 340SC and 370SC Service Model 2-13
Chapter 2—Functional Descriptions
As with the other indicators on that LED bar, the LED is in series with current
limiting resistor, so a lit LED indicates only the presence of a voltage, not
necessarily the correct voltage.
The control grid, G1, voltage is regulated to -81V during normal operation.
During blanking, G1 is pulled to -111V. When the CRTs are disabled for
protection, G1 is pulled to its maximum negative level of -200V, which can be
measured, at the control connector, pin 6.
2.5 Card Cage
The Card Cage provides support and protection for five (5) circuit boards, the
Phase Locked Loop and the optional Decoder Board in the HJT Model 330,
340SC and 370SC projectors. The five-(5) circuit boards are, from rear to front,
the VPB, RTG, SCB, VDB, and HDB. Each circuit board has it's own keyed slot.
A circuit board cannot easily be plugged into the wrong slot since the connectors
will not match up.
Horizontal Deflection Board (HDB) P/N 102523
Vertical Deflection Board (VDB) P/N 102521
System Controller Board (SCB) P/N 104668
Raster Timing Generator
and Phase Locked Loop
Video Processor Board
(RTG)
P/N 100568
(PLL)
(VPB) P/N 104672
and optional Decoder Board
Figure 2-9
Four (4) fans on the right side of the card cage cool the circuit cards in the card
Electronics Card Cage
cage. These fans are energized by the +24V standby power from the SPS. They
start when either the Arc Lamp or the electronics are powered up and run for
approximately five (5) minutes after the projector is shut down.
The five-(5) cards in the card cage are held into position by both the friction of the
connectors and by a circuit board retaining bar. The circuit board retaining bar
should always be installed during projector operation.
A lightweight top cover is included with the card cage. Eight (8) screws secure the
cover. The cover provides for direction of air flow and for physical protection of
the circuit cards contained in the card cage. The cover should always be installed
when the projector is in operation to ensure adequate cooling of the circuit cards
and to prevent foreign materials from falling into the electronics.
2-14 Model 330, 340SC, and 370SC Service Manual
The card cage is hinged in the rear to allow it to be folded backward for access to
the CRT housing (when folding the card cage backward be sure that nothing is
plugged into the rear electronic jacks or the plugs could be severely damaged).
During normal operation, the card cage should be in its upright position to ensure
proper cooling of the CRT enclosure.
A holddown screw is provided to secure the card cage and prevent it from rotating
backward during shipping or when the projector is mounted in an upwardpointing position. The holddown screw is located on the lower, front, right corner
of the card cage.
The rear panel of the card cage provides mounting for the projector controls. The
VPB, which receives all image and sync inputs, is secured to the rear panel by
four screws. The RS-232 control connectors and the IR receiver and repeater
inputs as well as the LED dot matrix status display are located on the lower left of
the rear panel. The projector model and serial numbers are also found on the rear
panel.
2.6 Circuit Boards
Chapter 2—Functional Descriptions
The Model 330, 340SC and 370SC projectors have a total of twelve (12)
accessible circuit boards. Seven (7) boards are located within the card cage
(Figure 2-9) and five (5) are located outside the card cage (Table 2-2).
Table 2-2
No. Description
Ignitor
1
Video Amp Boards (VABS)
3
Backplane
1
Each circuit board can be replaced individually except the Backplane board and
Circuit Boards Outside Card Cage
330
102083
103567
100571
340SC
102207
103567
100571
370SC
104475
103567
100571
the PLL. The PLL is replaced with the RTG as a unit. The Ignitor was previously
described in Section 2.4.2. The circuit boards covered in this Section are listed in
Table 2-3.
Table 2-3
Page
2-18 Raster Timing Generator
2-26 Horizontal Deflection Board (HDB)
2-34 Vertical Deflection Board (VDB)
2-44 Video Processor Board
Circuit Board
Circuit Boards
(RTG)
(VPB)
P/N
100568 and PLL
102523
102521
104672
and optional Decoder Board
2-55 Video Amplifier Board
2-58 System Controller Board
2-70 Backplane Board
(VAB)
(SCB)
103567
104668
100571
Model 330, 340SC and 370SC Service Model 2-15
Chapter 2—Functional Descriptions
Figure 2-10 on the following page provides an overall view of how the raster is
produced. Details on the individual PCBs are provided in separate sections in this
chapter.
2-16 Model 330, 340SC, and 370SC Service Manual
Chapter 2—Functional Description
Figure 2-10
Model 330, 340SC and 370SC Service Manual 2-17
Raster Generation Block Diagram
Chapter 2—Functional Descriptions
Raster Timing Generator Board (RTG) p/n 100568
The Raster Timing Generator board is located in the electronics card cage and plugs into
the backplane. It is the second board from the rear of the card cage and consists of a main
board and the PLL daughter board (see Figure 2-11). The PLL board must be installed for
the projector to operate.
Figure 2-11
2-18 Model 330. 340SC, and 370SC Service Manual
Raster Timing Generator Block Diagram
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