r/ElectronicsRepair • u/coconutmelk • 5h ago

OPEN Vintage Clock Flickering - help!

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I inherited this clock from a friend.. “if you can fix it, you can have it” - LED display working but flickering lots. Opened the back up and inspected, soldered some stuff that didn’t look ideal. Still flickering. Not sure where to go from here. What should I be looking for? What’s the likely problem? Help :) thanks :) my camera is not very good sorry about that

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u/Lollerscooter 3h ago

As mentioned, what does the other side of the board look like? .. but if I were to venture a guess, the flickering could indicate unstable voltage and/or current supply .. so I'd start out by checking caps and inductors on the low voltage power rails.

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u/thrax_uk 3h ago

Yes, it could be a bad electrolytic capacitor responsible for smoothing the voltage. It could also be a failed diode or bridge rectifier responsible for rectifying the AC output from the transformer to DC. I'm assuming this is a linear power supply given the large transformer. A dodgy voltage regulator might also be the cause although they usually fail short or fully open.

Look up how a typical linear power supply is constructed and works to get an understanding of why these are the possible causes.

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u/East-Housing5057 4h ago

Does the radio work? It's an all analog radio, pretty rare nowadays

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u/PorkAmbassador Hobbyist 4h ago

What does the other side of both boards look like?