David Cook
Well-known member
I've found a transistor in the ADB circuit thats corroded away, schematics says it's a MMBT2904, I can't find any for sale.. Does anyone know what a suitable replacement would be?
I believe you (and the Bomarc schematic) mean MMBT3904. You'll find plenty of them. : )
Edit: That transistor provides the output signal (low) to the ADB device. The specifications needed to do so are non-critical. Any small-signal NPN (bipolar) transistor will do. Given Apple's ubiquitious use of the 3904, the Bomarc schematic clearly has a typo on that page.
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