I have an old analog TV that starts working fine, but after some time the picture closes and it stops completely. I test the components and find nothing. How to solve the problem?
The worst defects for those who work with electronics are intermittent defects, those that manifest only in a few moments. Usually, when we turn off the device and the problem component cools or recovers from the problem, even with tests, we can not find it. You have to be quick and go straight to the tests the moment the problem happens. Leaving the appliance working open on the workbench to do the tests quickly is a procedure. However, most intermittent problems are caused by electrolytic capacitor problems. Try to examine them in the step that causes the problem and replace them with something that seems suspicious. Another suggestion is to use the freezer spray (see IP109 - Using the Freezer).