Peter G (sinetimore) wrote,
Peter G

Coin Toss

So last night, I had a killer case of insomnia.  With all my work caught up, I was free to pick something goofy to do.  So I went back to working on Orbital, my electronic arcade game.

Unfortunately, I was still stuck in the same spot I was last time -- in order for me to have that AUTHENTIC ARCADE EXPERIENCE, I want the machine to take coins.  And the coin comparitor was becoming a problem.  You can find them easily, but they cost $60.  While the price isn't going to break my budget (goal -- bring the machine in for under $500.  Current money spent -- $145), it does require a 12V power supply, and the game is going to run on 6-9V.  It looked like I was going to have to put in a separate circuit with power just for the coin comparitor.

I thought that maybe I could design a coin acceptor that wouldn't need power, just a trigger mechanism.  Originally, I was going to just use a photoelectric eye that would register when the coin dropped past it in the chute, but that was becoming complicated to program.  I was frustrated.  I see kids banks and tabletop electronic games that take coins, and those cost $20.  There had to be a way to do it cheap.  But how?

I had acquired some hobbyist plywood, like they use for making doll houses.  The idea was to make a coin acceptor and attack the coin wire to it.  The wire would trip when a coin went past it, and no extra power was needed.  But I couldn't figure out a way to implement it.

Defeated, I accepted that I was going to need to buy a coin comparitor and power it separately.  I went online to ask how to set it up, and one of the guys connected me with a friend of his who builds MAME cabinets in his spare time.  He would have all the answers I needed.

I told him what I was trying to do, and he asked, "Why don't you just use a microswitch?"

Because I haven't figured out how to engineer it.

"Just buy one."

....they make those?

"Oh, yeah.  You are shopping for an electronic coin comparitor.  What you need is a mechanical coin mechanism."

He sent me a picture of the comparitor.  No electronics, just gravity and physics.  I asked, Where does the sensor go?

"Oh, you put this in a standard holder to attach it to the machine.  At the bottom of the holder is the back channel assembly.  You put the microswitch in there, and the coin wire inside.  It does all the work for you." much does this cost?

"$20 for the mechanism, $15 for the holder and assembly.  I have some extra rolldown assemblies from the local DisneyQuest before it closed.  Free if you want one."

Yes, please.

It's going out in the mail today.  The only catch is, being a rolldown, it has to go on the front of the machine, not on top of the control panel.  But that's a small price to pay, and makes it look more like an arcade game.

But when I build my next one, I know what to look for.  Construction on Orbital resumes soon.

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