Quoted from EaglePin:
Put electrical tape over the bottom half of the opto opening. Helped on mine for both left orbit
Quoted from EaglePin:
I also put tape on the orbit opto. Shots going through the orbit at crazy speed hadn't been registering occasionally, and now it's registering them all.
So the tape thing clearly works, but I was looking for a more permanent solution. Here's how a few washers can fix this and it's pretty easy.
20191202_203021 (resized).jpgFirst you can check your opto alignment with a ball in switch test mode (I used some magnets to position it into the beam). My ramp was fine (I had to lift the ball over 1/4" to get the beam to detect), but both of my orbit optos were able to "see" the beam with the ball raised only about a 1/16". If the ball is flying it may sail over the beam, or at the very least get de-bounced with the bottom of the ball only breaking the beam for a very short time.
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So you're looking for this bracket for each of the optos. Take loose the 2 1/4 hex screws and unplug and remove the opto assembly.
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There are 2 philips head screws holding each opto plastic to the metal bracket. You want to remove these screws and slide a washer onto both screws underneath each opto.
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I had a 0.060" thick #4 nylon washer that was perfect. You can see the optos sitting up a little higher on the bracket.
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Reinstall the opto into the game and you're all set. As you can see the LED is slightly higher in the hole.
This makes all the difference, and now my optos don't fail to trigger unless you raise the ball over 1/4" high off the playfield. I've not had any fast opto shots fail to trigger after this fix.
Enjoy!