It seems like many times when I get to working on a game one or more bulbs are out. I'm talking incandescent 555 bulbs here, especially those mounted in those black twist-in wedge base sockets. But wait, there may be nothing wrong with some portion of those bulbs as when removed from the sockets they test good! The things I try to resolve the "bulb is out, but bulb is good issue" are all to often ineffective. I hate to throw things away that can be made to work.
So I'd like to ask - What do you try in order to avoid pitching those black twist in sockets and replacing with new at 99 cents a pop???
Things I try are:
> Meter the bulb to make sure it is good. If not, install known good new bulb.
> Rub the contacts on the 555 bulbs gently with very fine sandpaper to make sure "crud" isn't present.
> Spread the contacts away from the surface of the bulb a bit.
> Use a small screwdriver to bend the tabs inside the socket so they touch each other, to make a more firm "grab" once the bulb is inserted.
> Use a fine flex stone to lightly rub the inside edges of the tabs inside the socket, and also the metal tabs outside the socket that contact the circuit board when installed.
> Check header on the relevant circuit board to see if any pins need to be reflowed.
> Check surface on circuit board to see if good connection will be made when socket is installed. Clean and/or add a bit of solder as necessary.
> Make sure power is present at the socket mounting point on the circuit board.
Sometimes after all of these steps the wedge socket just won't light when installed with a known good incandescent bulb. At that point I install a replacement wedge socket and the lamp lights, end of story. At that point I have been discarding the bad twist-in wedge base socket, but I'd really rather refurbish them.
So, what else could be needed to get these wedge base sockets to work? They aren't physically broken inside (meter proves it)! They are simple items, so it should be possible to make them work!
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