TheYeti
Well-known member
I have a newly acquired Robotron and Joust. The Robotron is working 100% but the Joust didn't have sound.
Since the 2 games are so similar in hardware, I was able to swap the sound boards between the 2 games and quickly isolated the problem to the sound board. (Joust sounds started working but then Robotron sounds stopped) I'll work on the sound board later.
However, after I confirmed that sound started working on Joust...about an hour later the game screen turned yellow and displayed error 1-3-1 on the board's LED.
So I immediately checked the voltage reading on the Joust CPU chip and it was reading 3.1 volts. Yea...that's not good.
I suspected the issue was related to power so I removed and re-connected all the molex connectors on the power supply and it fired up just fine. (I eventually need to convert to Trifurcon connectors to avoid this issue in the future.
But now that the game turns on, I checked the voltage at the CPU again and now I'm getting 4.7 volts. Still low, but the game works so I guess that's OK?
So just for giggles I decided to check the CPU voltage on my working Robotron and to my surprise, the reading was only 3.2 volts!?
As far as I can tell my Robotron is working fine. So how in the heck is working with only 3.2v?
Since the 2 games are so similar in hardware, I was able to swap the sound boards between the 2 games and quickly isolated the problem to the sound board. (Joust sounds started working but then Robotron sounds stopped) I'll work on the sound board later.
However, after I confirmed that sound started working on Joust...about an hour later the game screen turned yellow and displayed error 1-3-1 on the board's LED.
So I immediately checked the voltage reading on the Joust CPU chip and it was reading 3.1 volts. Yea...that's not good.
I suspected the issue was related to power so I removed and re-connected all the molex connectors on the power supply and it fired up just fine. (I eventually need to convert to Trifurcon connectors to avoid this issue in the future.
But now that the game turns on, I checked the voltage at the CPU again and now I'm getting 4.7 volts. Still low, but the game works so I guess that's OK?
So just for giggles I decided to check the CPU voltage on my working Robotron and to my surprise, the reading was only 3.2 volts!?
As far as I can tell my Robotron is working fine. So how in the heck is working with only 3.2v?




