Inverter problem?

Thread Starter

burntfingers

Joined Jul 20, 2011
8
Got this Sansui SV-2615 LCD cutting off the screen, sound remains OK.
Needs switch off and on again to bring picture back [perfect picture].
Takes longer to shut screen when it's cold, and less and less as it warms up.

I checked the power board for d/js and used a computer fan to extract heat, to no avail.
 

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Kermit2

Joined Feb 5, 2010
4,162
Shotgun replace any electrolytic caps in the sweep drive circuit area/

(I seem to have suggested this on several topics lately) :)
 

Thread Starter

burntfingers

Joined Jul 20, 2011
8
Shotgun replace any electrolytic caps in the sweep drive circuit area/

(I seem to have suggested this on several topics lately) :)
Thanks.

The set is right now holding, since I installed a computer fan as shown in the picture supplied, blowing air into the components.
There is a small cap I'm going to replace soon, but could it be the chip, instead?
 

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#12

Joined Nov 30, 2010
18,224
It could be anything. Based on no drawing and no measurements, it could be anything. With this much information, the best anyone can do is recommend you to the most likely parts, and they are capacitors.
 

Thread Starter

burntfingers

Joined Jul 20, 2011
8
It could be anything. Based on no drawing and no measurements, it could be anything. With this much information, the best anyone can do is recommend you to the most likely parts, and they are capacitors.
So far, while blowing air on that IC, it is holding picture!
 

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Thread Starter

burntfingers

Joined Jul 20, 2011
8
This inverter IC could be the culprit, after all.
I haven't got one at the moment.
Just sent an email to Mastercare Sparescare, here in Johannesburg to see if they stock it.
I have told the customer that the set is holding nicely while the fan is going - a low noise one, by the way.
 

SgtWookie

Joined Jul 17, 2007
22,230
IC's can fail after many heating/cooling cycles. The expansion and contraction flexes the bonding wires that connect the pins to the substrate; eventually they develop metal fatigue and fracture, like bending the tab on a soda can back and fourth a bunch of times. They can still be in contact when cool, and then break contact when they heat up.
 
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