Hi,
I am trying to fix an opto error on my PM.
The emitter is lighting up, no errors in opto test (after removing J15).
How can I test the receiver?
(Topic ID: 203641)
Linked Games
Pinball Magic
Capcom, 1995
Topic Gallery
Hopkins, MN
Thanks for the article LTG.
I only think I need to align the opto.
I am definitely making an opto tester like you described.
3 weeks later
I managed to fix the opto, just re allign and all is golden.
But I have a new problem with another opto that stumps me.
I have changed the transmitter and it works. I have changed the emitter, not working. I have switched polarity, no luck. I have replaced it, no luck. I have reflowed the whole board, no luck.
I have measured the resistors, it has the same exact values as the rest. I have traced the connector to the board and we have contact. Still not working.
I am lost...
Help me LTG wan kenobi
Quoted from Axl:sadface
No, not a sad face. 
I can't help if you don't tell me what board you are working on.
You are correct GRUMPY , it is a poor way to ask for help without any background information.
The optos not working is for the genie mech. The mech was supposed to hold a 3 ball multiball, but it was never coded, but the optos are in the base code, and all three needs to be working.
I have exchanged the one transmitter and receiver with this part number A-16908 and A-16909. The one side is working when I test it against the old optos.
Here are some pictures from the manual.
39747C6F-196E-4B13-AFD1-AA262B564FB0 (resized).jpegBA84937F-384F-4BB4-99F7-DA9C420E25E3 (resized).jpeg2B540AD8-8340-474F-8033-A04DDB96F2C1 (resized).jpeg399B2D6D-3653-43D6-AA17-C3A6F0268CA1 (resized).jpeg69503138-BDC2-4634-8CF4-52451CD5ED30 (resized).jpeg
The ir receiver in your diagram has built in dropping resistor, are you installing a resistor across the new ir receiver?
Quoted from Axl:A-16908
This receiver maybe burning out when you power it up.
Quoted from GRUMPY:The ir receiver in your diagram has built in dropping resistor, are you installing a resistor across the new ir receiver?
I measured the resistor and it comes up with the same values as the rest. Would that happen if it is broken?
Also the Williams opto run at 12 volts in a Williams game and has a different voltage divider network ( The Shadow manual 3-21).
Not sure if you know but these are available at PBL.
http://www.pinballlife.com/images/products/thumbs/pbl-600-0202-00.jpg
Holy $#!+ those are expensive as each board has about $1 worth of parts on it.
http://www.pinballlife.com/index.php?p=product&id=4417
I wish I had a Capcom schematic of this part as without it, I'm only guessing as to how I would expect it to operate. 
Quoted from Pin_Guy:Holy $#!+ those are expensive as each board has about $1 worth of parts on it.
Maybe 3.00 dollars in parts. 
In an attempt to help here without knowing what is correct in the schematics as there are some obvious discrepancies between the schematics and boards shown on pinball life...if you measure across your receiver (optical transistor) with an unobstructed beam, you should measure a voltage drop of around 0.16V for the two PN junctions of the transistor ... I would assume anything > than 0.2V means the transistor is off.
Quoted from Pin_Guy:if you measure across your receiver (optical transistor) with an unobstructed beam, you should measure a voltage drop of around 0.16V for the two PN junctions of the transistor ...
Thanks for the guidance GRUMPY and
Pin_Guy
When i measure the original receivers I get 2.39 on both, on the new one, 2,48.
If I short the opto it is working. So I know the opto is good. Or is that a no no?
As a last resort, since the opto is not in use by the game. Can I short it? I would like to fix it though.
I have replaced the 2.7k resistor just in case.
Tried the game after shorting the non working opto, and the game plays fine in all aspects. I have that as a backup solution.
Now the stage opto is starting to behave erratic. I think that is the worst opto to fix. Lots of stuff to dig trough.
This is on another switch connector, so I don’t think they are related. I hope not.
Quoted from Axl:If I short the opto it is working. So I know the opto is good. Or is that a no no?
No, shorting the opto receiver means it's not working and you are bypassing it to get it to work. It could be off because it is either bad, or the transmitter is bad.
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