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I received this TV from one of my friend to repair. It is 10 years old and No diagram was found. The problem of TV was no power with pilot lamp on and fuse was not blown.
I used voltage testing method for repair of this set:.
Entrance AC voltage to bridge rectifier (LN4SB60) was good also 320 v dc On two poles of big cap mentioned that the big cap is running well. by assistance of goggle I found out that the vcc For STR (STRS6707) Must be 15 v DC but the voltage on the ic vcc pin9 was 7.5 v dc and This indicate that STR could be leaking the voltages
after changing The STR with new one the TV start to work but just for few seconds.(the sound was good ).
I check all other parts around second part of SMPS .also big transistor (HOT) of set was not giving good answer under test by volt ohmmeter (D1787). After substitution with (D2025) TV started to work steadily. But still no picture and only three Horizontal line on screen. This means no vertical deflection I proceed to vertical deflection ic in vertical section of the set it was hot like hell and also a big crack on the face of ic was visible this is (LA7830).
After changing this ic TV start to work also I got the picture very clear and sharp.
i want to mention that during the work on this TV I used isolator transformer for more safety