It's amazing sometimes how the simplest fix can be the solution to a perplexing problem. Such is the case in this example. Thanks for sharing, as it certainly could inspire other engineers not to overthink a puzzling problem in the future and perhaps find the solution where they least expect it.
This somehow reminds me of a Rube Goldberg system, where mechanical actions have unexpected consequences. I've also call it the "doctor is in" phenomenon: Before finding out what the problem is, it stops happening when someone who can fix it shows up.
One day in the 1980s, my wife called in a panic because our "portable" (read luggable) computer started going haywire. Keyboard characters were coming up wrong and things like that. I was at work at the time so it had to wait until I got home. The problem was obvious to me. She had put a book right up against the computer's vent, causing a temperature increase. Removing the book cleared the vent and all was well.
Rob, the statement about simple solutions mostly applies to simple problems. How often do we find that "For each complex problem there is a simple solution..... and it is usually wrong". Of course, many complex problems appear complex because they are not really understood, which allows all sorts of wrong conclusions and incorrect assumptions to develop.
In this vent posting it was not really clear as to why the heat rise problem was suddenly arising, when it had not been there before. While cooling the enclosure stopped the symptom it was not really solving the problem that something had changed. It was a good work-around, but it was not a solution.
OR, why was the heat rise causing a power supply problem. I replaced one which had a lot of small capacitors which the leakage changed as it got hot and the voltage drifted. Cheaper to replace with a new supply than to replace all of the drifting parts.
Some times are ignorance of the obvious solution can become a problem. We have a habbit of going to complicate things ourselves. It is always good to start with the most basic checks then to assume what might have gone wrong.
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