I've recently torn down and old printer as a learning experience and to maybe build something kinda fun out of it. As many will know that have taken apart printers, most newer ones have ceased using stepper motors and have started using a system of regular dc motors mixed with photo interrupters and optical strips to tell distance. A particular one photo interrupter I've come across a lot now has six pins out of its small black package. 2 I have determined are for the infrared led and the other 4 are for the phototransistor. Sadly, I can't find this little photo transistor on the internet and have instead resorted to the wonderful people here for some help. I removed it from the housing, figured that'd help a lot.

Here's a picture of the phototransistor removed from the photo interrupter housing.

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    \$\begingroup\$ Go to your favorite electronic components distributor (wonderful people) and buy a pototransistor with a known datasheeet. Cannibalizing components out of old consumer electronics doesn't make a lot of sense nowadays (at least in the developed world it doesn't). More on that here. \$\endgroup\$ – Nick Alexeev Jul 13 '17 at 22:00
  • \$\begingroup\$ @Nick Alexeev Not everyone is in developed world. \$\endgroup\$ – AndrejaKo Jul 13 '17 at 22:10
  • \$\begingroup\$ @NickAlexeev Any distributor you'd recommend? \$\endgroup\$ – Cosmic Floppy DIsk Jul 13 '17 at 22:11
  • \$\begingroup\$ Hobby grade: Jameco, SparkFun, Adafruit, your local electronic supply store, even RadioShack if they are still in business. Professional grade: DigiKey, Mouser. [All of these are in the US. The list would be different for other regions.] \$\endgroup\$ – Nick Alexeev Jul 13 '17 at 22:17
  • \$\begingroup\$ It isn't a simple photo-transistor: it is an integrated circuit, perhaps processing an array of silicon photosensors. Some types generate in-phase and quadrature outputs, but that's a wild guess. \$\endgroup\$ – glen_geek Jul 13 '17 at 23:46

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