Hughes JVC 100, Service Manual

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Chapter 2---System Description
Model 100 Service Manual 2-21
RED
GRN
BLU Video signals. about 0.7 to 1 VPP
HOR Composite horizontal / vertical sync signal
System Controller Board / RTG PCB
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. Bi-directional 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 Supply
Inputs Description
+5.1V +5.1V supply for use by YPbPr_VIC.
+15V + 15V supply for use by YPbPr_VIC.
-15V -15V supply for use by YPbPr_VIC.
Quad Standard Decoder/ Line Doubler VIC
The Quad Standard Decoder/ Line Doubler VIC has two basic functions. The
Quad Decoder accepts C-Vid and S-Vid signals in four different formats PAL,
SECAM NTSC and 4.43NTSC and converts them to a RGBHV signal. It contains
one BNC input connector for C-Video and two BNC connections for Luminance
(Y) and Chrominance (C) for S-Video. The Model 100 projector does not accept
sources with horizontal scan frequencies lower than 30 kHz. The Line Doubler
takes scan frequencies like NTSC (~15 kHz) and doubles it to ~31 kHz, which the
Model 100 can use.
The following functions are provided by the Quad Standard Decoder/ Line
Doubler VIC:
!
Select input source - Composite or S-video
!
Select standard-AUTO/NTSC/PAL/SECAM/4.43NTSC
!
Conversion of composite and S-video signals to RGB video signals
!
Separation of syncs from the input signal
!
Doubles the Horizontal Scan Frequency
!
Tint, sharpness, and color adjustment