Magnavox 42MF237S/37 weak picture

[Toasty]

Got this in a few months back and finally got around to working on it.

Initial complaint is that it would not turn off. Found about half of the main PSU caps blown. Did a complete recap of board and reinstalled. Set powers on and off with no issues in that area.

However, when initially starting the center of the screen looks like someone threw ink at it. The "ink blobs" slowly fade away in the course of about 2 minutes but the center of the picture vertically has a graininess to it and the overall picture is dim and weak.

Looking for some guidance here as to what to check.

Panel: Samsung 842AX

T

[freakaftr8]

Re: Magnavox 42MF237S/37 weak picture

I've had this same problem before same model. Couldn't cure it. The panels well used most likely.
Check vs and VA on startup..Also check vscan.

From the sounds of it it sounds like vscan may be low. Check this voltage against the panel label.

[Toasty]

Re: Magnavox 42MF237S/37 weak picture

Thanks for the input. I was thinking the panel was shot but needed some confirmation.

Have a manual or link? Elektrotanya doesn't seem to have this one...

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[tom66]

Re: Magnavox 42MF237S/37 weak picture

Z-sus or X-main with "ink blobs" problem. not panel.

[Toasty]

Re: Magnavox 42MF237S/37 weak picture

Was hoping you'd chime in.

What about the lightness/weakness of the display?

What issues should I look for on those boards?

Manual source?

T

[tom66]

Re: Magnavox 42MF237S/37 weak picture

What's the panel in it? LG or Samsung? LG usually have ink blobs issue with Z fault (picture can either be OK or it can be dim) whereas Samsung is usually only dim.

[freakaftr8]

Re: Magnavox 42MF237S/37 weak picture

That model uses samsung.

[Toasty]

Re: Magnavox 42MF237S/37 weak picture

Post 1 - Panel: Samsung 842AX

[tom66]

Re: Magnavox 42MF237S/37 weak picture

I'd check Ve and fuse on X-main then. Ink blobs rare with Samsung, but suppose it could happen.

[Toasty]

Re: Magnavox 42MF237S/37 weak picture

Still looking for a manual. Anyone?

T