Hulk score display problem on startup

[mgjock]

Hi,

My hulk (gottlieb solid state) has a score/display problem on startup. When i power on the machine, the score display seems in error therefore i cannot play a game. The 2nd and 4th player scores light up but show up muddled digits and 1st and 3rd players are blank with no score displayed.

Can anyoe enlighten me of possible problems? is it my switch settings? cpu board? any damage? or easy to correct?

what should i start looking at?

thanks

[Strangeways]

Check the SLAM switch on the door

[JRK1971]

In addition to what Strangeways said... I'd be checking your connectors from the power supply to MPU. And also check for correct voltages on the power supply and at the MPU. I've got a countdown and most problems are related to poor connector connections or dirty contact pads on the boards (from my experience).

Does the machine actually start up correctly, ie can you register a credit, push the start button and get a ball to eject into the shooter lane? This will tell you whether it is just a display specific problem, or the game not starting up correctly.

[Pintoxicated]

My first thought would be connector issues as well.  Have the connectors been re-pinned?

[mgjock]

thanks for your helpful advice. the problem was simply the two blue round knobs on the system one power supply. turning those knobs corrected the display. i must have move them accidently. does this makes sense to you?

not sure whether those knobs are for brightness of display or do something else?

thanks again

[Pintoxicated]

Sounds like you are talking about the pots which adjust your voltages.  Not really something you should fiddle with.  You should probably check the volatges now with a multimeter to make sure they are OK and not too far out of spec.

thanks for your helpful advice. the problem was simply the two blue round knobs on the system one power supply. turning those knobs corrected the display. i must have move them accidently. does this makes sense to you?

not sure whether those knobs are for brightness of display or do something else?

thanks again

[mgjock]

I have a multimeter but don't know how to use it and if I should check the voltages can you guide me on how to check it and what to look for?

[Pintoxicated]

I have a multimeter but don't know how to use it and if I should check the voltages can you guide me on how to check it and what to look for?

To start with I would have a good read through this.  http://www.pinrepair.com/sys1/index.htm#power

Basically you will need to remove the connectors from the power supply and check the voltages as described in the guide.  If you aren't to keen on doing stuff like this, I would recommend sending the board/s to ken/Skybeaux and they will come back in tip top working condition.

[mgjock]

thanks for the helpful advice