Mastodawn

paulrickards Jun 7, 2024

Got a Logitech ScanMan 32 handheld grayscale scanner for the Mac. I think it’s like the PC version but with an additional box to convert to SCSI.

I’ve never owned a handheld scanner before so this is going to be fun/awful. I want to try it with the #AppleLisaClone

#RetroComputing #VintageApple #VintageMac #Logitech #LogitechScanMan

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paulrickards Jun 7, 2024

First problem: the ScanMan, although practically brand new, didn’t come with the 12VAC power supply. And I don’t have one on hand. The original was 13.5VAC 1.2A.

However.

I’ve always been skeptical of devices that need low voltage AC. It’s usually rectified and regulated inside the device, right? So here’s the inside of the Logitech ScanMan 32 Mac box.

I see a couple of different regulators and one rectifier. Can one just use a DC power supply and it would just work?

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Sumilumi

@paulrickards DC of either polarity should work but it comes with some caveats. The circuit may or may not be sensitive to the effects of using rectification diodes which have quite a voltage drop and can be a source of electrical noise. This drop can depending on the circuit also shift 0V earth to well above or below which introduces all manner of ground loop problems if the device connects to anything external that is also grounded.