Baby Pac-man EOS

Reddogg

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Hey everyone, I replaced an eos on my Baby Pac's left flipper. But, I wasn't able to find an exact replacement, so I ordered a high current "tungsten" eos. However, it doesn't have a diode on it, and it only has 2 contacts on it. Now, when I play I can hear a hum when I activate the left flipper, and I've blown the 3 amp slow blow fuse on the power supply twice in a week.

Dokert has advised that I do in fact need a diode there, and while I don't question him, I'm curious as to how exactly it works on this Baby. When I compare it to the right side flipper, the part of the multi-layered leaf switch that controls the manual ball eject is the leaf switch with the diode, where the one without a diode is only attached to ground wires, and receives the spark. I also don't remember the leaf switch that I removed having a diode, so now I'm wondering if mine has in fact been wired wrong since I've had it.

Can someone confirm their setup?

Also, what kind of diode do I need. The manual doesn't say anything.

Thanks.
 


http://www.flickr.com/photos/beerorkid/5180897952/

you can zoom in on flickr

There is only a diode on the right flipper where there is a double stack switch and the top one activates the eject when you start in the pinball area. The diode on the eject switch contact is a 1n4148.

Via Lindsey

It's just a diode blocking a pretty low voltage. Pretty much any old diode (1n4001-1n4007) will do the job but if you're buying diodes you might as well go for something like a higher voltage rating. You might want to use them for something else and the price difference should be negligible. I'm sure Clay (pinrepair) suggests something specific in his guide. Go with that if they have them at Radio Shack. I'm sure they will have basic diodes.

EDIT: The schematic shows 1n4148 diodes (100v 200ma). Those are some pretty crappy diodes. I would go with what I've suggested above.

I have got a hundred 1n4001 diodes off of ebay for $3 shipped. I need to pick up some bigger ones.
 
Great! Thanks for taking the time to do that.

But, now my questions are, why am I getting a hum when I activate the left flipper, and why is the 3 amp fuse blowing at times?

Should I throw a diode on it to help it out?

Thanks.
 
Hey everyone, I replaced an eos on my Baby Pac's left flipper. But, I wasn't able to find an exact replacement, so I ordered a high current "tungsten" eos. However, it doesn't have a diode on it, and it only has 2 contacts on it. Now, when I play I can hear a hum when I activate the left flipper, and I've blown the 3 amp slow blow fuse on the power supply twice in a week.

Dokert has advised that I do in fact need a diode there, and while I don't question him, I'm curious as to how exactly it works on this Baby. When I compare it to the right side flipper, the part of the multi-layered leaf switch that controls the manual ball eject is the leaf switch with the diode, where the one without a diode is only attached to ground wires, and receives the spark. I also don't remember the leaf switch that I removed having a diode, so now I'm wondering if mine has in fact been wired wrong since I've had it.

Can someone confirm their setup?

Also, what kind of diode do I need. The manual doesn't say anything.

Thanks.

On a game of that era, a true EOS switch (a switch that "breaks" the flipper's high voltage) doesn't use a diode. Switches that use diodes are switches that are part of the switch matrix. Your EOS switches are not part of the matrix. Has the coil been replaced?....my guess, something's wired wrong...or maybe the EOS isn't adjusted properly (not fully closing and/or opening as it's supposed to).

Now, if you're actually talking about a "stacked" switch....yes, that needs a diode. Without a diode, the switch matrix will get "confused"......though, it won't cause a fuse to blow.
Edward
 
On a game of that era, a true EOS switch (a switch that "breaks" the flipper's high voltage) doesn't use a diode. Switches that use diodes are switches that are part of the switch matrix. Your EOS switches are not part of the matrix. Has the coil been replaced?....my guess, something's wired wrong...or maybe the EOS isn't adjusted properly (not fully closing and/or opening as it's supposed to).

Now, if you're actually talking about a "stacked" switch....yes, that needs a diode. Without a diode, the switch matrix will get "confused"......though, it won't cause a fuse to blow.
Edward

Yes, I replaced the coil with a brand new one when I did the EOS (that way things will just last longer).

It is NOT a double stacked EOS, so I'm safe there, no diode necessary, right? I'll check the gapping of it, but I'm pretty sure it's good.

The original one that I replaced was so badly pitted, that it couldn't be filed down. There was almost a hole in it. Maybe that was caused by too much power going thru it? Therefore, something is wired wrong?

Thanks guys for the suggestions and explanations.

If you've got more, please feel free.
 
Problem solved. The new leaf switch didn't come with the little white plastic piece which separates the "normally closed' switch blades when the solenoid fires. This of course caused the flipper to have constant current when activated = blown fuse.

Should've noticed it. Found the original leaf switch, so I just used that blade in the switch stack.

Anyone know where to get a leaf switch that has those white plastic pieces attached to them? Or are we all stuck adding an original piece to modify the new ones?

Thanks again.
 
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