ADAM restoration, a couple of questions

[AltRN8]

So I am trying to a restore an ADAM computer. I lacked the printer so I modified a PC PSU to power the system. I've ordered a new supply to dedicate just to the ADAM so this is a hold over. It was in unknown shape when I got it so I expected something to be wrong. After I powered it up all I got was a black screen and a tone. There is an intermittent sound like a startup sound sometimes but it just stays stuck.

 

I did a massive amount of digging on the forums and it sounds like the ADAM is very sensitive to power supply voltage drops. The -5v channel on my jury rigged one is only around -4.7-4.8 so I assumed this might be part of the issue. So, instead of just waiting for the new power supply to arrive I did a little more digging. The tech manual troubleshooting does point me toward the PSU being an issue but I wanted to confirm with the experts here if it might be something else. That way I could get started ordering parts etc. I've already ordered replacement caps so I can refurb the board but those are also in transit. Cap replacement is generally my next step but I'm unfamiliar with ADAM behavior so I'm looking for any particular anecdotes people can share. Even confirmation I'm barking up the right tree would be great.

 

Thanks! 

 

 

 

 

 

 

[AltRN8]

So I was able to build out a brand new PSU to work with the ADAM. Same state so it wasn't the power. I'm hoping to work on replacing all the capacitors on the board as a preventative measure and potential troubleshooting step. Is eBay the best place to look for the Video chip and CPU replacements? 

[pearsoe]

I have an ADAM that also had the black screen and tone on power on.  Fixed it by replacing the RAM on the ADAM logic board.

[AltRN8]

This is a great tip. I'll definitely look into replacing the RAM next. Thanks so much Pearsoe!