Macintosh 512k Boot Issue

[pl1984]

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[MacTech68]

Try "zip"-ing the sound file first. Then the forum should accept it for upload.

As for what's going on, it does seem that the particular analog board MAY be damaging logic boards. A picture(s) of that board may assist.

 

[pl1984]

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[MacTech68]

That's a Mac that needs coffee ! 😵🙄😉🙂

Standby whilst I consult notes - might be a little while - real life is getting in the way. 🙄😡

Check the +5v rail at least

 

[pl1984]

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[MacTech68]

One of two ways (using the chassis as ground) -

1. Via the floppy drive port - may need to use a straightened paper clip if multimeter probes are too big:

or

2. via the Blue wire on the power/video cable that connects to the motherboard.

 

[pl1984]

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