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Only for training and service purposes - 15 -

1. TV/CATV doesn’t display

TROUBLESHOOTING

2. DTV doesn’t display

Check the ou tput d ata of IC104 in the Jack
Board Pin52.
Can you see th e normal sign al?
NO Could you measure v oltage o f IC104 in the
Jack Board & IIC lines?
Are they all normal? NO You should ch eck p ower lin e
& IIC lines.
YES
You should rep lace Jack Bo ard.
YES
Check the ou tput o f Main IC(IC100).
Especially you sh ould ch eck
The H,V sync and c lock .
Can you see th e normal waveform?
YES
NO After chec king th e Power of Main IC(IC100) yo u
should decide to replace Main IC or not.
This board has big probl em because Main
IC(IC100) have some troubles.
After chec king thoro ugh ly all pa th onc e agai n,
You should decid e to replace Main Board or no t.
Check IC104.
Can you see th e normal signal?
Check the output o f TRQ105 in th e Jack
Board.
Can you see th e normal waveform?
Check the output o f Main IC(IC100).
Especially you sh ould ch eck
The H,V sync and cl ock.
Can you see th e normal waveform?
YES
YES
NO Could you measure v oltage o f IC104 in the
Jack Board & IIC lines?
Are they all normal?
YES
NO You should check power line
& IIC lines.
YES
You should replace Jack Board .
NO You should decid e to replace
TR Q105 in the Jack Boardor not.
NO After checking the Pow er of Main IC(IC100) you
should decide to replace Main IC or not .
This board has big probl em because Main
IC(IC100) have some troubles.
After checki ng thoroughly all path once ag ain,
You should decid e to repl ace Main Board or not.
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