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8 horizontal/vertical deflection pcb – JVC Model 200 User Manual

Page 59

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Chapter 2---System Description

2.3.8 Horizontal/Vertical Deflection PCB

The HVD board is located on the top side of the deflection cage in
front of the electronic card cage.

The Horizontal/Vertical Deflection Board I/O diagram (Figure 2-14)
and the list of inputs and outputs (Tables 2-10 and 2-11) provide
information for the technician to perform module level
troubleshooting.

The following functions are provided by the HVD board:
• Horizontal raster centering for all three colors
• Horizontal gate drive
• Switch mode power supply generating the required

proportional DC supply

• Horizontal width adjustment
• Horizontal retrace switch network
• Left/right pincushion and keystone correction
• Drive main deflection coils to provide horizontal raster scan for

all three CRTs

• Drive main vertical coils to provide vertical raster scan for all

three CRTs

• Vertical linearity adjustments individually for all three colors.
• Vertical raster centering for all three colors
• IIC

interface

IIC Interface

All adjustments for the HVD board are performed by the System
Controller via the IIC serial bus interface. This three wire bus
interface consists of a clock line, a data line, and an interrupt line.
The HVD board does not create any interrupt and the interrupt line
is not used for this application. Table 2-10 lists the adjustments
executed via the IIC bus interface (I = Input to HVD board , O =
Output from HVD board):

Model 200 Service Manual

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