On 2/15/20 10:47 AM, Patrick Finnegan wrote: > I'm not sure why the index sensors on both are broken, but not the write > protect notch sensors. Hopefully once the replacements arrive, replacing > that will fix the drives. The drives look pristine on the inside.
The biggest (and most misleading) issue with optical index sensors tends to be dirt. The phototransistor or LED gets obscured by crud and ceases to operate, even though electrically, it's fine. The same phenomenon accounts for many so-called "alignment" issues with floppy drives--the track zero sensor gets crud and the position at which the sensor is interrupted changes. It's a mistake to attempt to re-align a drive before cleaning the sensor. In reality, most floppy drives do not exhibit drifting alignment. --Chuck
