Panasonic gp8du gph8du th-37px50u th-42pd50u th-42px50u th-42px500u th-50px50u th-50px500u troubleshooting Service Manual

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 Z Board (Sound) SOS Detection
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Figure 46 
 
The 10V source of the Z board originates at the P board as 12Vdc. It is regulated to 10V 
by the PB board. It then passes through the PA and H boards before entering the Z 
board. The main 9V source of the PA board is also used on the Z board. It passes 
through the H board and then enters the Z board. On the Z board, the transistor Q2323 
monitors the 10 and 9 volts sources for a short. If a short is detected, a high output is 
provided to the base of Q2324 resulting in a low output to pin 15 of IC4005. Twelve 
blinks are generated when an abnormality is detected.  
 
 
 
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