Minolta DiMAGE Scan Elite II

[ttyr2]

I bought a used Minolta AF-2920 off of ebay in untested condition for use with my beige G3/MacOS 9.2.2. I knew it was a gamble.

When I received it, there was no sign of power other than a very brief motor noise when power was supplied and the power button turned on. Being as how there was no returns and no guarantees, I opened it up and found one of two thin ribbon cables disconnected. Once I plugged that back in, the status light on the front started working.

Currently the power LED blinks about once a second and each time it is turned on the scanner carriage servo inside turns a couple of degrees and then stops. After that, it doesn't do anything and never completes initialization. Likewise the scanner software doesn't detect the scanner.

I looked over all the capacitors with a good light and magnifying glasses and didn't find any that were obviously leaking or corroded.

Some of the documentation talks about a locking screw or pin that locks the scanner mechanism but I couldn't find it, and I'm able to gently turn the servo and move the mechanism with the power off with no binding.

Not having a schematic, I checked a couple of spots that were marked VCC and saw 5VDC to ground. That's as far as I got probing around.

What do you guys think?

 

[ttyr2]

Did some more diagnostic work today. What I think is the mirror scanner carriage underneath appears to move ok. If I pull the stepper motor (it has a worm gear that locks the carriage), move the carriage a bit, put the stepper back in and power it up, the carriage moves until it trips the flag sensor, so I think that part is good. Back on top of the unit, I was looking at the scanner strip transport assembly. That motor moves a couple degrees on power up and then stops. Even if I crank that mechanism a ways so the flag sensor (separate from the sensor on the bottom) is not obstructed and power it up, the carriage doesn't reset. I noticed the small circuit board that is soldered to the sensor was tweaked a lot, like bent probably 10deg or so from square with the sensor. I straightened it and did a basic LED test on the emitter and it appears good (infinite resistance one direction, .987v the other direction). I read online that my cell phone should see the LED light as purple when the sensor is powered up. I'm going to try powering the sensor back up and so a voltage reading on the phototransistor when I move something in and out of the slot.

There are no markings on the sensor so I'm not sure how to source a replacement. I thought about gambling on buying another dead/parts scanner just to rob the sensor out of it.