While I do not recommend smashing power bricks on the floor, I certainly agree with opening them to see what has failed. Poor solder connections are one of the easy to repair problems, and I am happy that the repair has continued to work for you. Of course, being open with no case probably makes the power supply run a lot cooler, which also helps.
This was a good fix; don't know that I would have realized what the problem was and fixed it. We had an office copier that was always on the fritz, finally bought a manual, and was told to fix it. It worked for the entire 12 year time I was there, but they finally stopped making parts for it.
I used to have problems with my laptop power bricks regularly after I burned my original power brick. After that i started buying the cheap ones(not original ones). They used to heat up real quick and then eventually they would stop working. I was really annoyed by this, since I had to buy a new powerbrick every time this happend. But when this happend with my last powerbrick, I got really annoyed and smashed it on the floor, it poped open, and then I saw that the connector pin was actually loose. Then I realised that because of so much heat the solder must have melted, leaving the connector pin loose( that explained why the led light used to flicker when I pressed the connected cable inside).
I soldered the connector pin back with my soldering iron and Bravo!! it is still working till the present date :).
Now, probably I will not throw my powerbricks away and waste money.
Replacing a fuseholder not sized for the application is one area that does make sense, and as long as a similarly rated fuse is used, or the same type in the better holder, there should be no problem. But it is important to understand just exactly what the fuse is supposed to be protecting, and how that protection must occur. Sometimes the fuse must clear very rapidly so as to avoid a fatal dose of power to some item, while other times the fuse is intended to protect something from overheating during a much longer instance of a minor overload. And at all times the fuse must be able to interrupt the power in case of a massive short circuit.. So there are some considerations.
In the case of the cranky techmician, some are simply unwilling to ever admit any product deficiancy, while others presume that their knowledge, however small it may be, is all inclusive. There are also situations, such as I had at one job, where the boss had a standing order to never admit to anything being an equipment problem, even if we were fixing something for free under warranty. And it is also quite possible that they knew exactly what the problem was and refused to fix the steady source of income. Or, it could have been a good tech having a really bad day.
Back in the days when my hair was a lot closer to the top of my head, a friend came over with his Fender guitar amp for repair. It needed a couple of new filter capacitors, and my buddy said, "I'm tired of CHANGING FUSES!!" So, as a part of the repair I replaced the 3AG fuse holder in the chassis with a circuit breaker. He still talks about how GREAT that idea was, to this day- "I just push the button, and keep on Jamming!"
I once watched a repairman reseat an internal connector on our (then) recently purchased Mitsubishi DLP TV with an apparent overheating problem. I think I offended him with an ill-timed comment like "I could have done that". When he left, the TV no longer worked -- investigation revealed he had left the connector disconnected. That was easy enough to fix, and with a little help from various forum posts, the problem was eventually solved by bending the contacts in the connector to ensure a solid connection for the temp sensor wires. Unfortunately it seems people can at times be easily offended when their knowledge or expertise in a particular area (which may be tenuous) seems threatened.
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