Tda8172&stv9379whats difrent i have 2 ics no 1=tda8172 no2 =stv9379 is its same

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Failure of vertical sweep output. Check all the solder terminals of vertical output IC, for any loose solder. It is best to resolder all the solder terminals to this IC, by applying a little more solder to each solder terminals to that IC, without making any solder bridge short in between adjacent solder terminals.

there is an ic defect ic 561 stv9379
also check resistor r526 0,47ohm

Hi,
According to the symptom on A Board +13volts not being supplied, and this is due to IC561 Details(Part No. and Description) of IC is given below:

8-759-980-58 IC TDA8172

which is not working please replace it and your tv work fine again.
Thanks for using fixya.

Happy to help. Thanks for the update.

Dan

in theses set's there should be a board that has a module that the power chord plugs into this module supllies the motherboard and the componants on it. to be honest it would be best to just let a professional replace any defective chips orboards at this point because i believe it is not just one problem but several and without me beibg hands on it would be difficult to narrow it down to just a simple answer.

Most likely IC 541 is faulty on the A board. The IC number is TDA8172

MAN/WOMAN I GOT SIMILAR PROB. HOWEVER I AM SHORT OF CERTAIN DETAILS. IT IS ALL ABOUT THE VERTICAL SECTION. THIS IS THE PORTION THAT PRODUCES THE FRAME. IC TDA8172 IS USED FOR THIS AMPLIFICATION. CHECK TYPICAL PIN VOLTAGES AND ASSOCIATED CAPACITORS AROUND. CHECK VERTICAL SCAN COIL IMPEDANCE. TRY FURTHER BACK, THE ACTION OF IC CXA2159S. I DO NOT HAVE ITS PIN CONFIG. I NEED IT.OUR PROBLEM IS HINGED AROUND ALL THESE AREAS.

Picture int disappears leaving snow on screen
Resolder the Xtal in the tuner
No picture - screen is empty. Sound is ok
Check IC101 (BA7630F), if video signal comes to input (pin 1) but not present at output (pin 14) then replace this IC
Intermittent video or snow
Resolder points A, B, C, D in tuner PCB, check cold solder on tuner shield 2-106-349-21

the vertical o/p generic number stamped on the fron of the ic is "TDA8172" the sony part number is "8-759-980-58". good luck