How to wire test and service only from a jamma harness?

Thomas

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How to wire test and service only from a jamma harness?

I have the need for a test pattern so I can align a tube swap I did today. I don't need anything else but that test pattern.

I have a mk1 or mk2 board sitting here running straight off a jamma harness. No controls no nothing.

I have two small momentary push buttons. How would I wire this to access that test pattern?

14 Service to?
15 Partside to?

Would it be ground for both tied together?
 
I have the need for a test pattern so I can align a tube swap I did today. I don't need anything else but that test pattern.

I have a mk1 or mk2 board sitting here running straight off a jamma harness. No controls no nothing.

I have two small momentary push buttons. How would I wire this to access that test pattern?

14 Service to?
15 Partside to?

Would it be ground for both tied together?

yeah, you could have both go to the same ground, just attach them both to a couple of cherry switches or something.
 
In order to save yourself some time in the future, get a 2-position (3 lug) slide switch with an alligator jumper attached to the center lug and another attached to one of the outer lugs. Then you can just connect it to the board on those traces and flip the switch to enter and exit whichever mode you want to use.

Now, if you do bench testing a lot (like I do), then you mount a 3 position switch (left, middle, right) somewhere and wire it into your test JAMMA harness with the center position as off, left as test, and right as service (label them). Makes it pretty easy to pop in and out of test.

Of course, for MK1 and MK2, you can activate the test menu by simply turning on dip switch #8 of Bank #2. Of course, without any controls (joystick and buttons) you won't be able to navigate the menu or select anything to get to the screen you want...
 
just to throw this out, with MK1, the test switch has to be a toggle/slider switch that can stay in the normally closed position... can't be momentary like the kind for MK2, otherwise you'll have to manually hold the test button down the whole time while operating controls and such in the MK1 test menus. lol

so I second mod's suggestion.
 
Thank you guys! I have a lot better idea on how to wire this test station up now...
 
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