Magnavox 32mf339b/f7 no power

[MountainMike]

Got a 32" magnavox that will not turn on no lights nothing. Fuse ok, caps look ok. Any suggestions are greatly appreciated? Thanks

[selldoor]

Re: Magnavox 32mf339b/f7 no power

What is the Voltage on the Red and Black cables near the big cap in the first picture.
CARE Very high voltage 1.41x mains. so set meter on 600vdc

[MountainMike]

Re: Magnavox 32mf339b/f7 no power

169 vdc

[selldoor]

Re: Magnavox 32mf339b/f7 no power

ok well that is spot on for120vac so now you need to test for low dc voltages

somewhere on the links to the main board section of that board - I just hate them.

If they are not labelled and you dont find a schematic service manual I would just try testing for vdc voltages up to 50v on the diodes radiating out from the yellow transformer ( on the secondary (cold) side)

I am off to bed now perhaps others will join in.

[jstiene]

Re: Magnavox 32mf339b/f7 no power

Mountain Mike

any luck with finding your problem. Your post came up on a search as I have a 32MF338 with the same issue..dead...was wondering what you found so far..

[sansonet]

Re: Magnavox 32mf339b/f7 no power

I just fixed this model, in my case it was SB390 Diode (D642 on my board). Borrowed the same diode from different board and it fixed it. Now I need get replacement, but closest match that is available for shipping is SB3H90 - will it work?
http://www.digikey.com/scripts/DkSea...14663043682765
This is link for original diode http://www.digikey.com/product-searc...376383?k=SB390

[retiredtech30]

Re: Magnavox 32mf339b/f7 no power

this tv is service friendly heres the tech manual