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Home▸ Forums▸ Macintosh II Series 1/2 AA Battery B2: Alternative Solutions — #1▸ Macintosh II Series 1/2 AA Battery B2: Alternative Solutions — #1
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Hello all, 

I recently received a Macintosh IIx that had its soldered PRAM batteries removed.

I believe battery B2 provides the voltage for the power supply to start up once the power button is pressed.

Since I didn't have any 1/2 AA batteries/holders I soldered a 9v battery to B2. The Mac did not come on when the power button was pressed.

After this I removed the 9v battery and replaced it with a AA battery holder, supplying 3v altogether. The Mac did not start in this configuration.

What am I missing? Do batteries need to be present in B1 and B2 for the Mac to start?

 I'm sure a similar technique was shown inside a Macintosh II on an episode of Jason's Macintosh Museum.

mp.ls