Another BSD Opto Problem – FIXED

Alright, I’ve read every thread I could find on BSD opto issues. I’ve also tried everything I can think of. I’m totally STUMPED.

Issue:
Everything on my BSD works great, but the LONG opto switch doesn’t work at distances further than 6 inches apart. The long opto is used to see if there’s a ball on the magnet as it moves across the playfield. I CAN get the long opto to work, but only if I physically place them close together to test them. They just won’t work at the long distance required (across the playfield).

Fixes I’ve tried:
-Swapped in different opto boards (both of them). No change.
-Swapped in a good half dozen opto senders AND receivers. No change. The receiver can’t pick up anything beyond about 6 inches of distance. I used NOS Williams/Bally’s senders/receivers.
-Swapped in a new shield cable for the opto. No change.
-I even picked up this:
http://www.mcmelectronics.com/product/72-6771?green=779DAC1E-97AC-51DD-B070-DAAAF2FF2F95
The infrared detector card showed me exactly what I thought was happening. It showed the infrared beam more focused up close. At distance, the infrared (as shown on the detector card) washed out/spread out… until at distances beyond about 6 inches, the receiver can’t pick it up more.
Thoughts? I’m REALLY stumped on this one. Is there a long distance (focused) opto I’m supposed to be using? If so, where the heck would I find them? I can find plenty of optos, but nothing that doesn't wash out past 6 inches or so.

Thanks in advance!

Yep, they're definitely A-14315(LED), A-14316(Trans)... which are unobtainium. From what I can tell, they were replaced by A-16908 and A-16909. I don't know about the originals, but the replacements (A-16908 & 9) wash out after a few inches.

Curious about this statement... I've got Cointaker LEDs in my BSD. How could LEDs be potentially causing an issue with the optos? Thanks!

Thanks for the idea. I originally thought this might be it, but I now know the optos are working... but washing out over the long distance. If I physically bring the long optos together... to a range of the rest of the optos on the playfield, they work just fine. They just can't handle the distance.

No lens on the BSD optos... Well, it's simply a domed LED.

I wondered if this might be the issue... but I pulled the optos out of the machine, and I can't get them to "see" each other beyond about 6 inches. I tried a handful of the A-16908 and A-16909's, but they all wash out after a few inches. By 6 inches distance, they can't "see" each other.

I was guessing the opto was washing out at distance... then I got this and proved it:
http://www.mcmelectronics.com/product/72-6771?green=779DAC1E-97AC-51DD-B070-DAAAF2FF2F95

At around 1-3 inches, it's the opto makes a pencil diameter sized mark on the IR detector card. Move it further back, and it totally washes out. No chance of it actually shining across the playfield IMO.

Thanks! I ordered some to give them a try. I can easily solder them into the board. Hopefully, that'll do the trick. I'll post results after they arrive.

I haven't done that... but that's a good idea! I'll have to check.

I was also considering fabricating my own lens or tube to focus the IR across the playfield. You know how it goes... potential pin solutions pop in your head at 2 AM... and then you have to go and try and see if it resolves the issue.

I decided to do exactly that... order placed.

So, I've got some new (old) optos on the way... and the homepin board. Hopefully, one or both things will fix this prob once and for all. I'll post updates once I get it all installed. Thanks everyone!

Yep... Have the empty opto body in front of the receiver on the left side. Thanks for the idea though.

Voltage was/is fine. Posting fix in msg. below.

Update:

So, I finally got my back BSD up and running perfectly. The solution? It was two-fold and complex:

First step: I installed the Homepin card (works/fits great). When I installed that card, suddenly the receiving Mist eye “woke up”. In the Mist/magnet test mode, it was now noting that the beam was projecting across the playfield. Initially, I thought my problem was fixed. Not yet… While the receiving opto was indeed now detecting something, it wasn’t detecting the transmitting opto from the other side. Why would it be noting it was receiving a signal even when I blocked the transmitting eye on the other side of the playfield? I suspected the nearby GI lighting might be causing the problem. So, I pulled the GI LED near the receiving eye. That fixed the false opto signal. However, the standard transmitting opto on one side of the playfield STILL wasn’t reaching the opto receiver on the other side of the playfield. Below is a link to the transmitting opto I was using (I tried 3 or 4 of these in case I had a bad one – it didn’t fix the issue):
http://www.marcospecialties.com/pinball-parts/A-16908

Second step: I installed a different transmitting eye:
http://www.marcospecialties.com/pinball-parts/A-14231

I used that eye, and swapped the plastic housing from the other eye. BINGO. It now works PERFECTLY.

Note: the opto from the bottom link that finally worked IS definitely a different color than the opto in the top link. Maybe it's the fabled "long range opto"? The opto in the top link was far darker than the near clear looking opto in the second link. For whatever reason, the 2nd opto seems to be able to hold it’s beam (focus) all the way across the playfield.

So, if you’re having problems with your Mist function on BSD and it involves switch number 82 – the fix I’d recommend is: Install the Homepin card. If that doesn’t fix your problem, I’d also install this opto, and just swap the plastic housing from your existing opto. http://www.marcospecialties.com/pinball-parts/A-14231

This problem stumped me for MANY hours. I hope this write-up helps someone.

Just a thought here... maybe the different opto board is doing something (good or bad) to the volts on one of your GI lights near the switch 82 optos? Maybe that slight fluctuation is causing your switch 82 to falsely see/not see what it thinks is the switch opening/closing? That long range opto has a long ways to shoot compared to the rest of the game's optos.

Try removing the GI bulb near the receiving opto and see if you notice a change. If that doesn't work, you might want to also try the transmitting opto that helped fix mine (just swap over the plastic shroud - 1 screw):
http://www.marcospecialties.com/pinball-parts/A-14231

Best of luck!