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Cranky old novice
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"Capacitor Dissease" is well known in the electronics industry and has affected plenty of equipment. The early S3's were of the vintage to be most likely affected. This problem and replacing the caps has been mentioned on this forum numerous times.

Tivo obviously buys power supplies, and probably the mother boards, from vendors so it's not surprising if one vendor used bad caps and another didn't.

Hope you ordered "low ESR" premium caps!

There's even a bad cap web site:
http://www.badcaps.net/
 

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Cranky old novice
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9,467 Posts
Is is absolutely necessary to replace caps with the exact same voltage as specified on the cap? I picked up two 1000uf 35v caps to replace two bulging and split 1000uf 10v caps in my TCD652160 PS. Everywhere I looked online said that higher voltage is ok and safer. Maybe I just did a poor soldering job.
I'm surprised the 35V caps weren't MUCH larger than the 10V versions, to the point of being hard to fit in. When charged to rated voltage the 35V cap contains 10 times as much energy (goes with voltage squared). You don't store 10X the energy in about the same volume unless you're compromising somewhere else in the cap design (e.g., not low-ESR and lower temp rating).
 

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Cranky old novice
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9,467 Posts
Update: I opted not to mess with the power supply any further because I discovered that if I hit the "Live TV" button after the video goes out and then change the channel, the video returns without having to force a reset.
Have you checked the voltages -- this behavior isn't normal (unless your system always acted this way even before the PS went bad).
 

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Cranky old novice
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9,467 Posts
I just call a failed capacitor a failed capacitor, replace it, and when I'm done I'm glad it was a cheap easy fix, but you guys go ahead an enjoy pages long debate about whether it's called capacitor plague, capacitor disease, or called nothing at all...
This
 

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Cranky old novice
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9,467 Posts
....... how do you get the existing capacitors out before putting the new ones in? I haven't removed the power supply board yet. Do I melt the solder on the bottom of the board where the capacitor join? .......
First I add my vote to solder suckers over wicking --- maybe just my poor technique but I never had much luck with wick.

Here's what I recommend:
General warning: Try to minimize stress and heat on the printed circuit board at all times.
1. Heat the solder pad at each cap lead wire (on the underside of board) enough to melt the solder (but not any more than that) and use the sucker to remove as much solder as possible. Do this for both leads of the cap.
2. If there is enough lead wire exposed to make it practical, snip the excess lead.
3. Now heat each pad just enough to melt while rocking and gently pulling on the cap. Alternate this between the two leads and repeat until the cap is free.
4. Use heat and sucker to clean the through holes to facilitate inserting the new cap. (Observe polarity!)
 

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Cranky old novice
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9,467 Posts
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I have seen a MOV short out and since it's across the AC in I think it would be a good idea to remove it just for testing. I think he is going to have a hard time finding the short on this on. I had one that was popping fuses it was the Xformer shorted out and I have no idea where to find one. It would be nice to have schematic on this unit. By the way how have you been?
MOV's also wear out as a function of the number and severity of spikes that they are exposed to. I believe they go open circuit in this case, which means there will be no obvious symptom (other than lack of protection).
 
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