Magnavox 20MT1331/17

[kevflanaman]

I have a Magnavox 20MT1331/17 and all of a sudden one day when i turned it on the picture moved to the bottom of the screen. There is a 3 inch black bar at the top of my screen. I'm more familiar with computers since i never repaired a tv before. But i refuse to go to a ripoff tv repair shop. Any help would be greatly appreciated. Thanks guys

[kevflanaman]

any help would be great
Thanks guys

[fongs]

Hi,

Sounds like vertical deflection problem.

I would focus on the frame (ie. vertical) IC and/ or capacitors around it. I dunno abt yr TV but alot of them use the vert IC with the "LA7xxx" number. U shouldn't miss it as it is usually mounted on the heatsink...

G o o d luck!!

[kevflanaman]

thanx alot man for the help. that's all i needed to know. Ur the BEST!!!! take care

[fongs]

U R welcomed!

I would try re-soldering the vert. IC 1st... I fixed a Panasonic 21" with similar problem just by doing that.

If that doesn't work, a replacement of the IC and/ or the caps around it is worth a try. Do a google search to look for the data sheet of the IC to identify its pin out. This will tell u which are the caps supporting this IC.

Let us know how it goes...

[kevflanaman]

Im kinda new to this, exactly where is the vert ic. located? thanx

[Guest]

[kevflanaman]

i took out the main board and I can send you pictures if that help. I apreaciate u halping me man.
thanks, kev

[tjgmore]

I'm an old tech and my niece has the same model and problem. what i found without a schematic was a shorted power diode(ref#6463) just left of the flyback(high voltage) transformer. after replacing diode with fast switching cross reference, I still have same problem but new diode is still good. I then found resistor(ref#3543) measured 82kohms but color code is brown,red,black which means it is 12ohm. That is either a misprint or resistor is bad. after soldering board and checking components, i need a schematic to diagnose further. If somebody has resistor(3543) value let me know or I'll have to spend $20-$30 for manual.

[Hect7369]

Resistor is good R5343(82k).
Check cap 2465,this fails often.check all surround components.