JVC Model 200 service manual Scan Reversal Board

Chapter 2---System Description

		Horizontal/Vertical Deflection Board I/O
		This section provides a description of the inputs to and outputs
		from the HVD Board. The I/O descriptions are arranged by the
		source/destination of the signal. The assembly communicated with
		is used as the primary heading of each group of signals. Those
		signals are subdivided into inputs and outputs. Input refers to an
		Input to the HVD Board, output refers to an output from the HVD
		Board.
Table 2-11.	Horizontal/Vertical Deflection I/O signals
		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 the System Controller Board and the HVD Board.
OUTPUTS		DESCRIPTION
/IIC_SINT		IIC interrupt line. This is not used by HVD Board.
		Video Processor Board
OUTPUTS		DESCRIPTION
/SWEEPOK		Low = good scan. High = no scan. Signal is dependent on two
		inputs; DEFL_OK (from SRB) and /H_ENABLE (from RTG).
		Scan Reversal Board
INPUTS		DESCRIPTION
FRONT/REAR		Front or rear projection status line. Front = low. Rear = high.
FLOOR/CEIL		Floor or ceiling projection status line. Floor = low. Ceiling = high.
DEFL_OK		Deflection OK signal. High = good (about 2 v). Low = no scan.
H_CUR_		Horizontal current feed back. A DC voltage proportional to the output
FDBK		current.
H_LOCK-		Horizontal interlock for yoke connectors. It should be 5 V when
		closed or 0V when open.
V_RED-		Current feedback of red vertical amplifier
V_GRN-		Current feedback of green vertical amplifier
V_BLU-		Current feedback of blue vertical amplifier
OUTPUTS		DESCRIPTION
H_OUT_		Horizontal output flyback pulse, about 800 VPP
FLYBACK

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