Anyone can do board repair, First time owning hardware

[TotalEconomist]

So I just recently bought my first JAMMA board (Raiden Fighters 2) and there's some issues with it.

- Inconstant video display. We tested the board on two different PCB cabs with the same harness setup. Video showed up on one and not the other.

- 1p doesn't fully operate. In other words, it doesn't recognize right commands on the stick.

- Doesn't read the coin op. Did on the first few runs but then suddenly stopped working.

Any help would be nice.

 

[XtraSmiley]

Look for damaged traces, corrosion, busted caps, bent pins on chips etc. Also properly remove and reseat all chips.

Pics here might help.

 

[ShootTheCore]

Check your supply voltage as well - ideally you want between 5.0 and 5.1 volts.

 

[TotalEconomist]

Check your supply voltage as well - ideally you want between 5.0 and 5.1 volts.

Where would I find that? (Assuming we still talking about the board and not the machine).

 

[djsheep]

After powering a board, use a multimeter and touch the black lead to ground and then the red lead to 5v on the Jamma edge. The power section on the Jamma connector is the smaller 6 pin section. Turn off the power, adjust as necessary using the pot/knob on your PSU and re-measure.

When measuring voltages, make sure your black lead is always on one of the two pins at the very end of that 6 pin section. Your have to be careful when doing this to make sure you don’t bridge any of the pins which can cause smoke.

 

[nem]

Turn off the power, adjust as necessary using the pot/knob on your PSU and re-measure.

No need to turn off the power, better to keep it on so you don't overshoot. If you have a friend and there's two of you, one can keep the meter leads on the connector and the other one can adjust the pot. Of course you could do this by yourself too (holding both leads with one hand), but there's always the risk of slipping one of the leads and creating a short.

 

[ReplicaX]

Turn off the power, adjust as necessary using the pot/knob on your PSU and re-measure.

No need to turn off the power, better to keep it on so you don't overshoot. If you have a friend and there's two of you, one can keep the meter leads on the connector and the other one can adjust the pot. Of course you could do this by yourself too (holding both leads with one hand), but there's always the risk of slipping one of the leads and creating a short.

This.

I always set to 5v no load (no pcb connected)
Power off
Connect PCB
Power On
Adjust 5v while on

Better safe than sorry and a good habit to have.

 

[djsheep]

I always turn off the power. Adjust then power on. As long as you’re using a crappy board it doesn’t really matter.