Tech: TAF Opto Switch # 57 works when close but not from far

[cdnpinballer]

I've been working on and off trying to solve this problem on my TAF for over a year.

Switch # 57, Bumper Lane Opto is not working when installed in the game. This is the opto that activates the thing mini-flipper to shoot the ball into the swamp.

I posted on pinside seeking help a year ago here: https://pinside.com/pinball/forum/topic ... st-3073454

The puzzling part to this problem is that the opto works when close together up to about a 1/2" apart but any farther and it doesn't work.

I have replaced the opto's and connectors on the 7-opto switch board with no improvement.

I read +1.45V across the opto transmitter points A & K. Voltage to ground readings at point A is 1.50V and point K is 52.7mV.

I read 9.4V across the opto receiver points C & E. Voltage to ground at point C is 4.26V and E is 13.7V.

Does anyone have any ideas about how I might be able to solve this problem?

 

[cdnpinballer]

Problem solved!

I ended up taking the advice of a pinside member who replied on my thread.

"There are opto receiver LEDs out there that are misassembled from the factory. If they are installed according to the markings or lead length, they behave as you are describing. If you've ruled out everything else, unsolder the receiver LED, turn it around 180 degrees, and resolder."

Desoldering the receiver opto and turning it 180 degrees fixed the problem.

Nice to finally turn the game on with no error and credit dot! At least for now.

 

[Menace]

Glad you got it sorted. Another issue for those ordering replacement opto sets from Marco, I have found lately that the new batch they are selling are faulty right out of the bag. (I've had at least 2 sets like this) Maybe it's the same issue where the receiver is just installed backwards.

D