English Amiga Board - View Single Post - HELP

D94pam · 21 October 2021, 12:20

Thank you very much for valuable information. The route to check functionality using the keyboard matrix I hadn't thought of. Brilliant!

Unfortunately everything is still dead. I tried a couple of different keypresses using this method.

But one thing that struck me when looking at the schematics (https://www.amigawiki.org/dnl/schematics/A600_R1.5.pdf) is the circuitry handling the power up reset. One of the caps there is an electrytic one and even though the machine has been recapped and the area looks at least ok (the problem area in this machine was caps located on the right side of the mainboard handling audio where pads/traces had been eaten up). But there might still be some issue here, so I will dig out my oscilloscope checking the signals are doing what they are supposed to here.

Maybe you have any other idea though that I can also look into? Or am I on the right track you think?

Thanks!!

21 October 2021, 12:20	#5
D94pam Registered User Join Date: Jan 2019 Location: Sweden Posts: 5	Thank you very much for valuable information. The route to check functionality using the keyboard matrix I hadn't thought of. Brilliant! Unfortunately everything is still dead. I tried a couple of different keypresses using this method. But one thing that struck me when looking at the schematics (https://www.amigawiki.org/dnl/schematics/A600_R1.5.pdf) is the circuitry handling the power up reset. One of the caps there is an electrytic one and even though the machine has been recapped and the area looks at least ok (the problem area in this machine was caps located on the right side of the mainboard handling audio where pads/traces had been eaten up). But there might still be some issue here, so I will dig out my oscilloscope checking the signals are doing what they are supposed to here. Maybe you have any other idea though that I can also look into? Or am I on the right track you think? Thanks!!