I've built an "Arcade Test Unit" by making a rig that can test a PSU, a monitor, a game board, voltages, etc and be as adaptable as possible to what parts you have on hand.
Additionally, this box was made so that it could act as an 'emergency arcade machine heart' as everything can be connected externally so that you can simply plug in your devices (control panel, coin mechs, etc) and be up & running in minutes.
Main features:- Can be used to test any jamma (or non jamma with converter harness) game board, including those that require a kick harness.
- Has an internal power supply, and can also be used to use/test an external power supply.
- Has an internal CGA to Svideo/Composite video converter, and can also output regular RGB to arcade tubes.
- Has an inbuilt voltage tester.
Pictures tell a thousand words, so:
What you can see (left to right):- The molex connectors on the left allow you to plug in an external control panel to test player 1 or player 2 (or both)
- Coin, start, and test/service buttons, as well as RCA sockets for the coin buttons (so that you can plug in/test external coin mechs).
- Headphone socket and 'audio out' selector switch (switch between headphone socket and mirrored left/right RCA sockets on the rear panel).
- Volume knob
- Banana plug power INPUT OR OUTPUT ports. With the 'power selection switch' (between the ground and -5v), you can isolate the internal power supply from the banana plugs (which remain connected to the harness). This way you can use the internal power supply, OR connect/test an external PSU.
- Power switch (under the ground) for turning on/off the CGA to Composite/Svideo converter.
- Status LEDs (top/blue=main power, bottom/green=video converter)
What you can see (left to right):- In the upper left is a digital voltage meter. There is a selection switch on the side that selects the 5v, 12v, and -5v lines, and there is also an external connector for using it to testing AA, AAA, and 9v batteries (why not?). Because I've configured the volt meter to run off a 9v battery source, it can be used independantly of the unit having any power.
- A joystick and three buttons connected to Player 1. Full P1 and P2 can be tested using the molex connectors on the front.
What you can see (left to right):- On/off switch for voltage meter.
- Input selection for voltage meter (source: the 12v, 5v, -5v banana sockets on the front, which means you can test internal or external power supply by using the power isolation switch on the front
- A kick harness connector (connect buttons 4 through 6 for player 1 and 2 to a board that has more buttons than a standard jamma harness can handle)
What you can see (left to right):- Status LEDs in action.
- The fuse-protected AC input switch/socket.
- (not visible) Underneath the power socket is a hole to adjust the 5v knob on the internal PSU.
What you can see (left to right):- Regular arcade RGB output
- Composite + Audio Left/Right (mirrored) RCA outputs for regular TV, + Svideo output. This uses an internal video converter from in2amusements.
- A video output selection switch (select between RGB output and Svideo/composite)
- Ventilation hole (I've since added a 12v fan behind this grille that only powers on when the internal PSU is used).
When you include the jamma-to-jamma extention harness (to allow me to put the game board underneath that laptop stand I used), I have lost count of how many solder points this project required, but it was in the hundreds. That's what I call soldering practice!