76FW-54H. DA100 Repair Notes - Sharp TV Service Manual (repair manual). Page 53

DA100 (50Hz) Chassis – Article for Television Magazine 

This television chassis has the capability of directly controlling a VCR via the SCART socket or the 
VCR controlling the television. In either chase the VCR must be compatible with the ‘AV Link’ system, 
also during the installation of the television and VCR it will be necessary to decide whether it is the 
television or VCR which has overall control. 

 
 

Data from the television to VCR is from IC1001 pin 16 via Q1005 and is outputted from pin 10 of 
either the AV-1 or RGB SCART sockets. Data from the VCR is from the same SCART connection but 
this time it is fed into IC1001 pin 92 via D1003. D411 provides protection from excess voltage being 
applied to the SCART sockets.   

Normally faults associated with the microprocessor cause the television not to function, i.e. turn on or 
operate correctly.  By checking the signal on pin 36 (ALE), it can be seen that the internal system is 
undertaking instruction cycles.  This pin changes state at each instruction cycle that the processor 
executes, so it is a good indicator that the IC is working.  The normal frequency of this square wave 
signal is 8.77MHz. 
 
 
 

Sharp Electronics (UK) Limited - March 2003