Hughes Model 230 Projector Service Manual

Chapter 2---System Description
Model 230 Service Manual2-9
Voltage: 20 to 23 VDC to maintain the arc lamp ON.
Current: 55 to 70 amps to maintain the arc lamp ON.
LAMP_OUT: Lamp output voltage, positive.
LAMP_RTN: Lamp return.
/LAMP_LIT: Signal to SCB that the lamp is lit.
Operation:
Two signals (/COVER_ON and /LAMP_OK) are required in order for the arc
lamp to light. /COVER_ON from the cover interlock switches tells the Arc Lamp
Power Supply that the covers are in place and the interlock switches are...

Chapter 2---System Description
2-10Model 230 Service Manual
ARC GND
G2 SUPPLY
G1 SUPPLY 
 /H V  O K    T O   C R T S   V I A   V A B
R FOCUS  J58-1
G FOCUS   J59-1
B FOCUS  J60-1
T O   C R T S
R ANODE   J58-1
G ANODE  J59-1
B ANODE  J60-1
T O   C R T S VIA VAB
  H PARABOLA
FROM CD BOARD
  V PARABOLA  +80V
FROM LVPS
 +15V
  -15
 /HV ENA (/VA_OK)
  H VPS_SYNC
FROM  RTG
J45
5 11
J44
J45
13 14
8
9
10
12
6
13 (From VPB)
HIGH
VOLTAGE
POWER
SUPPLY
Figure 2-5.  High Voltage Power Supply, I/O Diagram
The HVPS...

Chapter 2---System Description
Model 230 Service Manual2-11
ARC_GND Return (ground) line for the CRT anodes
CONVERGENCE/DEFLECTION PCB
INPUTS DESCRIPTION
H_
PARABOLAHorizontal parabola for use by the dynamic focus amplifier
V_
PARABOLAVertical parabola for use by the dynamic focus amplifier
SYSTEM CONTROLLER PCB
OUTPUT DESCRIPTION
/HV_OK The high voltage status line. Low = operational HVPS
LOW VOLTAGE POWER SUPPLY
INPUTS DESCRIPTION
+ 15V + 15 V for use by the HVPS
+ 80V + 80 V for use by the HVPS
- 15V...

Chapter 2---System Description
2-12Model 230 Service Manual
•  Optional HDTV VIC used for High Definition Television.
•  Optional Quad Standard Decoder VIC used for NTSC, PAL SECAM and
other composite sources.
Graphics Enhancer RGB Video Input Card
The Graphics Enhancer RGB VIC is located at the rear of the projector. It has
five BNC inputs. It provides the RGB and sync interface for the projector.
The following functions are provided by the RGB VIC:
•  Video and sync interface for red, green and blue
•...

Chapter 2---System Description
Model 230 Service Manual2-13
Table 2-2.  Graphics Enhancer RGB VIC IIC communication
I/O Bits Information Description
I 1 /SEL_CH Select line for the Graphics Enhancer RGB
VIC. Low = Selected RGB VIC.
O 4 VIC_ID VIC identification lines. 0000 for RGB_VIC.
O 1 VIC_MODEL Revision of the RGB VIC.
O 1 /VIC_OK RGB VIC status line. Low = operational RGB
VIC.
The Graphics Enhancer RGB_VIC I/O
This section provides a description of the inputs to and outputs from the
RGB_VIC. The...

Chapter 2---System Description
2-14Model 230 Service Manual
SYSTEM CONTROLLER BOARD
INPUTS DESCRIPTION
IIC_CLK IIC clock line. Unidirectional clock line for control of synchronous
data transfer over the IIC bus interface.
IIC_DATA IIC data line. Bidirectional serial line for synchronous data transfer
between system control board and the RGB_VIC.
OUTPUTS DESCRIPTION
/IIC_INT IIC interrupt line. RGB_VIC does not initiate an interrupt.
LOW VOLTAGE POWER SUPPLY
INPUTS DESCRIPTION
+5.1 V +5.1 V supply for use...

Chapter 2---System Description
Model 230 Service Manual2-15
RED_VIC
GREEN_VIC
BLUE_VIC
H_VIC
V_VIC
IIC/SEL_VICIIC_CLK
IIC_DATA
IIC_INT
+5.1Vstby
+5.1V
+15V
-15V
4:1 
VIDEO
MUX
and
BUFFERS
RED_CH1
RED_CH2
RED_CH3
RED_CH4
GRN_CH1
GRN_CH2
GRN_CH3
GRN_CH4
BLU_CH1
BLU_CH2
BLU_CH3
BLU_CH4
HOR_CH1
HOR_CH2
HOR_CH3
HOR_CH4
VER_CH1
VER_CH2
VER_CH3
VER_CH4
Figure 2-7.  Quad Input RGB VIC
The same functions performed by the Graphics Enhancer RGB VIC are
performed by the Quad Input RGB VIC. The description of...

Chapter 2---System Description
2-16Model 230 Service Manual
•  IIC serial bus interface
RED
GRN
BLU
HOR
/SELECT Y/G
Pb/B
Pr/R
IIC_CLK
IIC_DATA
+5.1V_STBY
+5.1V
+15V
-15VB2
B4
B6
B8
B12 B13
A13
A16
B16
B15
B14
Pin callouts are to P12, P14, 
or P18, depending on which
VIC slot is being used.
Figure 2-8.   HDTV YPbPr VIC Input/Output Diagram.
This VIC accepts two types of video signals, color components (YPbPr) and
RGB signals. In either case the output of this VIC is RGB type signals. If the
inputs are...

Chapter 2---System Description
Model 230 Service Manual2-17
Table 2-4.  HDTV VIC IIC Interface
I/O BITS INFORMATION DESCRIPTION
I 1 /SEL_YPbPr Selects YPbPr input mode for the
YPbPr_VIC.
Low = Selected YPbPr input mode.
I 1 /SEL_RGB Selects RGB input mode for the YPbPr_VIC.
Low = Selected RGB input mode.
I 8 GAMMA Data for adjustment of Gamma correction
I 8 COLOR Data for adjustment of color
I 8 HUE Data for adjustment of hue
I 8 SHARPNESS Data for adjustment of sharpness
O 4 VIC_ID VIC identification...

Chapter 2---System Description
2-18Model 230 Service Manual
HOR Composite horizontal / vertical  sync signal
SYSTEM CONTROLLER BOARD
INPUTS DESCRIPTION
IIC_CLK IIC clock line. Unidirectional clock line for control of synchronous
data transfer over the IIC bus interface.
IIC_DATA IIC data line. Bidirectional serial line for synchronous data transfer
between system control board and the YPbPr_VIC.
OUTPUTS DESCRIPTION
/IIC_INT IIC interrupt line. YPbPr_VIC does not initiate any  interrupt
LOW VOLTAGE POWER...