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10 scan reversal board – JVC Model 200 User Manual

Page 71

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Chapter 2---System Description

2.3.10 Scan Reversal Board

The Scan Reversal Board (SRB) is mounted vertically on the right
side of the card cage.

The following functions are provided by the SRB:
• Reversal of scan in both horizontal and vertical axes
• Horizontal width adjustment for each color (R, G &B)
• Horizontal current feedback
• Scan failure detection for all six main (horizontal and vertical)

deflection amplifiers

The Scan Reversal Board Input/Output diagram (Figure 2-16) and
the list of inputs and outputs (Table 2-15) provide information for
the technician to perform module level troubleshooting. Table 2-14
shows the signal states for modes of projector operation.

The SRB does not require any IIC bus interface.

Table 2-14. Scanning signal states

Mode of Operation

FRONT/REAR
line

FLOOR/CEIL
line

Front and floor projection

Low

Low

Front and ceiling projection

Low

High

Rear and floor projection

High

Low

Rear and ceiling

High

High

Model 200 Service Manual

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