Hi,
As part of our development we are also making some replacement boards for those hard to find pinball parts.
We have developed a microcontroller board for the Gottlieb System 80 machines that is an exact drop in replacement but with these added features:
(1) One shot operation that can be switched between four different output pulse times to change game play and better suit different games
(2) Addition of a protection diode on the board in case the one on the coil fails/breaks
(3) Three LEDs to indicate status - Power on, input triggered and output active pulse
(4) Two second start up delay at power on to allow the game voltages to settle (output is muted during power up delay)
(5) Test switch on the board to 'fire' the output pulse - aids in repair and testing
(6) Uses a cheap and easy to get 2N3055 output transistor (why didn't Gottlieb do this?)
(7) Optocoupler driver to prevent damage to driver circuitry in case of output transistor failure/short
The original darlington output transistor used on these boards is almost implssible to find these days (and expensive if you do find one) as are the two obsolete IC's used on the original board.
We do not have a System 80 machine nearby to test the PCB in an actual machine and so I would like to ask someone who does have one, and preferably is either technically minded or at least is very familiar with their machine, to plug it in and put it through its paces for us.
The prototype (pictured) has done extensive bench testing.
http://www.homepin.com/pics/NGPCB.JPGPlease PM me if anyone is willing to assist - the first one to help can keep this prototype as a spare.
Cheers,
Mike
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