I have taken the advice from my earlier post - re-soldered all headers pins, checked connectors, etc...What I am seeing is that the flickering starts with the 6 Lamp board (Credits and Ball in Play) after it warms up (5-10 minutes of play) and then goes to the 3rd player and 4th player modules. On the Credit and Balls in Play board, I see resisters R1, R3, R5 & R7, R9, R11 (100k) along with C2 that looked as if they have gotten hot (dark spot down the middle of them) and also C2 has the same look.

I also see that R23 on the Player 4 - 7 lamp module has been replace and is sitting above the board (larger resister and does not lie flat to board). I have attached pictures of the resisters with C2 that look to have gotten hot and also a picture of R23 that is sitting above the board.

Should I replace all of these resisters (100k and 1.5k) and C2 (.05MFD 500v)? If so, should I replace the 100k with a larger value?

While I'm on the subject, Q22 appears to have been removed (still see leads in the holes) from Player1, Player2, Player3, and Player4 (7 lamp modules) boards - why??? (Picture also attached of this)

Thanks again,
Joe S.

100k_heated_resisters_(resized).JPG

Q22_Missing_(resized).JPG

R23_raised_(resized).JPG

I can order the 555 timer but what type of capacitors are C16 & C17? I know they are rated at .01mfd and .1fd but are the ceramic, radial, axial, etc...?

Thanks for all the help!

I replaced the 555 and the 2 caps around it. I still have flickering and now a buzzing/humming sound when it warms?????

Any other items to try or look at?

It appears as if I have corrected the issue. Another person suggested that I look at the high voltage regulator and C26 - I resoldered the leads on this capacitor and also (from another post) the IC on the digit display - pin 13...... I no longer have flickering display - thanks all!