J
Juan
- Jan 1, 1970
- 0
I have a Sony KV-35S26 that I acquired with a bad power supply and
shorted HOT. It was deader than a doornail.
Using information acquired from these posts, I replaced two switching
transistors in the power supply (2SC4834), the HOT, and the blown
fusible resistor (0.1 ohm R607) on the power supply.
Voila! The television works great--except . . .
After the set is on for a while, all of sudden the right side of the
picture starts to contract and cave in. Then the horizontal deflection
gives way to a picture that contracts into the middle and goes black.
At this point I've always quickly turned off the set, assuming that if
something's not oscillating I'm probably on the verge of shorting out
the parts that I just replaced.
I let the set sit--sometimes for 30 seconds, sometimes for a couple of
minutes--and when I turn it on again I once more have a very nice
picture. Then after another few minutes of running, the same thing
happens again. It starts to get fuzzy and contract along the right
side, and then it collapses.
I should also mention that when I replaced the HOT, I also went through
the HOT circuit and meticulously resoldered every connection (there
were a few that looked like they might have had ring cracks at the
solder joint). I also resoldered the flyback transformer.
The intermittent nature of the problem after the set's been on a while
makes me wonder if it's heat related. In addition to the components
mentioned above, are there other common failure points in the
horizontal output circuitry?
I sincerely appreciate any help you might be able to offer.
Best wishes,
Juan
shorted HOT. It was deader than a doornail.
Using information acquired from these posts, I replaced two switching
transistors in the power supply (2SC4834), the HOT, and the blown
fusible resistor (0.1 ohm R607) on the power supply.
Voila! The television works great--except . . .
After the set is on for a while, all of sudden the right side of the
picture starts to contract and cave in. Then the horizontal deflection
gives way to a picture that contracts into the middle and goes black.
At this point I've always quickly turned off the set, assuming that if
something's not oscillating I'm probably on the verge of shorting out
the parts that I just replaced.
I let the set sit--sometimes for 30 seconds, sometimes for a couple of
minutes--and when I turn it on again I once more have a very nice
picture. Then after another few minutes of running, the same thing
happens again. It starts to get fuzzy and contract along the right
side, and then it collapses.
I should also mention that when I replaced the HOT, I also went through
the HOT circuit and meticulously resoldered every connection (there
were a few that looked like they might have had ring cracks at the
solder joint). I also resoldered the flyback transformer.
The intermittent nature of the problem after the set's been on a while
makes me wonder if it's heat related. In addition to the components
mentioned above, are there other common failure points in the
horizontal output circuitry?
I sincerely appreciate any help you might be able to offer.
Best wishes,
Juan