magnavox 37mf337b/37 parts advice

[Welchs101]

Re: magnavox 37mf337b/37 parts advice

hi, i have a very similar power supply board from a TV model number
(47MF437B/37 Phillips / Magnavox). The board is very similar. I have the same exact diode that is failing....P4KE250A.

also looking for a replacement diode for this?

[ryan74]

Re: magnavox 37mf337b/37 parts advice

Oops. I replaced the blown caps and powered on for 10 sec..
Front led flashed fast and continuous red.

I must have missed checking it first time through.
Thank you for the link.

Just curious- what usually happens when you run it.

[budm]

Re: magnavox 37mf337b/37 parts advice

@ryan, that must be one those common failure diode in the snubber circuit, do not try to run without having new one installed.
http://www.mouser.com/Search/Product...p%252btw%3D%3D

[ryan74]

Re: magnavox 37mf337b/37 parts advice

I need help identifying, or finding a replacement zener diode.
I cant find a free datasheet for crossreference, and I dont know enough to figure it out myself.
Location(zd906) and part number(LT7228 P4KE250A)

[tom66]

Re: magnavox 37mf337b/37 parts advice

PLEASE DO NOT TALK IN CAPITAL LETTERS. IT MAKES IT SEEM LIKE YOU ARE SHOUTING.

It sounds like the repair shop doesn't know what the fault is, I wouldn't trust them. They sound like they just swap boards rather than try to diagnose the problem.

Here, I just uploaded the service manual:
http://www.tgohome.com/ServiceManual...&Search=Submit

[RICHARDRAY]

Re: magnavox 37mf337b/37 parts advice

ANYBODY OUT THERE CAN HELP ME WITH A PROBLEM WITH MY MAGNAVOX 37MF337B.. THE MAIN BOARD IS BAD OR SO I HAVE BEEN TOLD (PROIR TO THAT IT WAS A POWER SUPPLY WHICH AFTER I REPLACED IT THE REPAIR SHOP SAID IT IS NOW THE MAIN BOARD) I WAS LOOKING FOR ONE ON EBAY AND LOCATED A BOARD THAT THE GUY CALLED A T-CON BOARD PART # 6870C-0088D VER.1.. IT THIS THE BOARD i NEED ? BETTER YET, IF YOU CAN SEND ME TO A WEBSITE THAT WILL SHOW A SCHEMATIC, DIAGRAM OR LIST OF PARTS FOR MY TV SO I CAN "SEE" WHAT I AM LOOKING FOR.. I SEEN THIS BOARD BEFORE WHEN I BOUGHT MY POWER SUPPLY BUT CAN'T FIND IT NOW NOR KNOW THE LANGUAGE SO ANY HELP WOULDBE WELCOME.

[selldoor]

Re: magnavox 37mf337b/37 parts advice

Its alot easier to look at a pic than have to remember everything.

It is one of the reasons I press people to supply good clear pictures - they also
help with future queries when parts are burnt out.

[zombslayer]

Re: magnavox 37mf337b/37 parts advice

Parts are on the way! Checked D912 out of PSU it came back faulty. I will be using UF4007 diode for that replacement.P6KE120ACT ZD will be used for ZD902 ,and the three caps will be replaced with Panasonic EEU-FR1V102. Killian6pk, great point! Its alot easier to look at a pic than have to remember everything. I will update with progress as soon as parts are installed. Thanks again! Much appreciated!

[killian6pk]

Re: magnavox 37mf337b/37 parts advice

Make sure you are keeping a written record where all these parts of coming from on the board. You sometimes get so many you forget from time to time. I also like to take a picture of the board before I start taking parts off of it.

[zombslayer]

Re: magnavox 37mf337b/37 parts advice

I will search for the chassis number, I am interested in that now. The diagram is great in showing how the diodes are used, very interesting stuff.

[budm]

Re: magnavox 37mf337b/37 parts advice

The diagram I post is not the exact as your power supply, but it shows how the Diodes are used.

[zombslayer]

Re: magnavox 37mf337b/37 parts advice

I will definitely take D912 out,confirm the body numbers and diode test . I really appreciate all the input, I could not have done it without BADCAPS!! Thanks for the schematics as well VERY HANDY thing to have.

[budm]

Re: magnavox 37mf337b/37 parts advice

Digikey:
http://www.digikey.com/product-detai...ACT-ND/2770358

That is pretty low voltage rating for Snubber.
The other Diode D912 more likely to be UF4007, but take it out of the circuit to check and get the number off the body.

[zombslayer]

Re: magnavox 37mf337b/37 parts advice

ZD902 is p6ke120a/744, now that i do see it. I am guessing i should replace with a P6ke120a? Thanks.
Diode tester reveals .019 and .019 out of PSU.

[budm]

Re: magnavox 37mf337b/37 parts advice

From the picture, I can see KE2XXX. I do not see KE12XX. I expect it to be P6KE2XXX. I expect it to be 200v Zener.
His circuit may be similar to this one. I need to find the chassis number to look up the service manual.
http://www.mouser.com/ProductDetail/...k9x0jN%252bFfF

[selldoor]

Re: magnavox 37mf337b/37 parts advice

"Any number on that PKE ZENER Diode?"
Thought he has already said twice it is a KE1274

[budm]

Re: magnavox 37mf337b/37 parts advice

Most PHILIPS/MANAVOX TV's have chassi number printed on the model number sticker to tell the service technician which chassis being used inside the TV since same model can have more than one version of the chassis. Any number on that PKE ZENER Diode?

[zombslayer]

Re: magnavox 37mf337b/37 parts advice

PSU # is 715T2484-4, there is a barcode also on PSU with ADPF24220R1P/P5PB74752533 as I am not sure what those numbers stand for. The back of the tv its self has model# and serial #.

[budm]

Re: magnavox 37mf337b/37 parts advice

Is there a chassis number on the model number sticker?
Pleas remove that zener diode, it should have number with PKEXXXX on it, it is Zener Diode for the snubber circuits, will be in 200V range.

[zombslayer]

Re: magnavox 37mf337b/37 parts advice

I will do that! When I do find the info. I will be sure to pass it on. I will keep this thread open and update my progress. I am pretty good with electronics, this is my first tv and is a good learning experience.