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What specialty controller should be reproduced next?

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horseboy:

Ok, I thought about it and the button in front method would work if the button was wired as Normally Closed, but bouncing would be a big issue as you said. Still though, having the button pressed when the plunger is pulled back serves the exact same purpose as that overly complicated solution and eliminates the bounce.

Tekman:


--- Quote from: horseboy on August 23, 2006, 02:16:12 pm ---
--- Quote from: Tekman on August 23, 2006, 01:27:26 pm ---
--- Quote from: RandyT on August 20, 2006, 05:10:06 pm ---
--- Quote from: mark shaker on August 20, 2006, 03:44:24 pm ---I think what he meant was that you can use a standard plunger to push a button hooked to a keyboard encoder to the Normally Closed leads, so that when the plunger was pulled back the circuit would be closed and in effect press the enter key, when the plunger was released the circuit would be opened releasing the enter key.

The thing that the circuit adds over a simple switch is to remove any bouncing when the plunger was released.


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Correct, except that the circuit is only really required because of the method used.  The plunger does bounce a bit upon release, even on a real machine with a ball in play, and mechanical interference between the parts will greatly minimize this anyway.  A little bounce in PinMAME at ball release has no effect, so the net gain for all the trouble and expense is "zip".

Again, interesting approach, but it's like smashing an ant with a 30lb sledge. ;)

RandyT

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I originally thought a simple mechanical switch would be the best choice. It only took a couple minutes to figure out that will NOT work. Here is why:

- You get an unrealistic "thud" sound as the plunger rod hits the stationary switch

- The switch really takes a beating from the plunger rod. It only takes a few minutes for the switch move out of position and eventually things will break.

I realized a QRB1134 IR Photo reflector was the best choice. Here is why:

- No "thud" sound with the plunger having to hit something stationary.

- No wear and tear or broken parts.

Both of these ideas require a debounce circuit. I'm not sure how you came up with the statement that bounce will not affect VP. I found VP is VERY susceptible to bounce issues. Some tables will seem worse than others. The rod will hit the mechanical switch and still bounce on and off the switch until everything settles. We're talking several mS of bounce at a time until a solid condition occurs, which is usually never an issue with a human finger holding a button. You will find that the ball launch becomes very intermittent and will not even launch at all most of the time. This is tried and true.

I found out there is no "sweet spot" to mount the switch. The closer it is causes more damage and farther away has more bounce issues. You will find yourself fussing with this all the time and realize it is not worth the problems.

I haven
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