Vertical sweep problem Sansui dtv2798 scan lines on top of screen, need schematic or part no. of vert. sweep cap. thanks, Joe

Contact Sansui or purchase the schematic, I don't think your going to find anyone with the information you need on here as if it has a vertical out IC its a really old set.

Sounds like vertical sweep output section circuit fault. If you wish to get some details; check the site linked here. Pull up older posts. Surf the site with patience. http://electronicshelponline.blogspot.com/
Type in this key phrase " my service table today " in the search box at the top right of the display window, to get gathered some pages which has the details of practical experiences to the author of that site with similar faults that he have repaired.

Check and replace the vertical scan output IC. Check related capacitors, and solder terminals at the vertical scan output section circuit for any loose soldering. Check the voltages at the vertical scan output IC. Refer its circuit diagram [schematic] for more details. If you wish to get some details; check the site linked here. Pull up older posts. Surf the site with patience. http://electronicshelponline.blogspot.com/

Diagonal retrace lines at the top are usually the result of bad electrolytic capacitors in the vertical deflection circuit most vert. deflection circuits derive operating B+ from a horizontal flyback transformer winding rectified & filtered usually around 24 volts the electrolytic capacitor on this supply loses capacity or may totally go open causing the retrace lines,sometimes other electro. caps in the vert circuit can cause this too, depending on the age of the tv you may find multiple substandard electrolytic caps it's best to test all for capacity & esr. Without knowing more details about your tv brand,model and/or chassis i can't help further.

The vertical and horizontal adjustments are out of sync.

I HAVE A SANSUI TV MODEL DTV2798 AND THE VCHIP IS ACTIVATED. I DO NOT HAVE THE CODE. DOES ANYONE KNOW HOW TO FIX THIS ISSUE?

Yes. It takes a while to scan for all the channels.

replace vert IC301, C432, ( D431 & R431 should also be blown)

hi, the problem is in the vertical ossilation.. let me know

you have a vert sweep colapse. Fisrt thing is to get a schematic diagram and find the vert. output Ic and the clamper diode. Measure the voltage on both sides. If its low then its apossibility that the Ic was drawing loads of current and blew out the b+ feed resistor. Look on the schematic and trace back the voltage line from the vert output ic back to the sweep power supply on the secondary of the flyback transformer. check the limiter resistor to the feed and if its open replace the cap right there the resistor as well as the vertical output Ic ALL AT ONCE!!! If you dont you will cause it to go out again in a short time. Good Luck.. If you post the vert part of the schematic I will be more then happy to assist you with this repair.