Good afternoon all,
I have acquired two Mac Plus units of which neither want to boot.
I've started with the usual logic and analog board cleaning and recapping to no avail.
The most promising combination of boards only achieves a white horizontal line accompanied by noise from the speaker, as seen in this video:
Other combinations of board only achieve a flupping noise at various speeds with a blank screen.
Nothing seems particularly broken on any of the boards, except scorching underneath the 5W 1Kohm resistor on both of the analog boards, both of which tested open and have subsequently been replaced.
I know there are a lot of variables at work here and not having a working system to swap parts and narrow down the problems makes it more difficult to diagnose, but are there any specific areas that need checking/replacing to start off?