Scanner Testing

Scanner testing is done at the scanner testing station in printerland. This is the desk at the extreme NE corner of the warehouse (next to the windows that are covered with black carboard).

The test computer set up there has both standard and development scanner backends.

Most of the scanners we keep are USB, but a few are SCSI.

USB

1. Select a scanner
2. Locate a suitable power supply
   • Locate the output voltage and amps specifications on the bottom or side of the scanner.
   • Locate a power supply that matches the scanner for both its voltage and its amps.
     • Most scanners use a 12V 1.25mA (1,250 A) positive center power supply, but there are many exceptions.
     • It can be helpful to mark a 12V 1.25mA power supply as a functioning power supply with which to initially test scanners since this is a common power supply. After a scanner with 12V 1.25mA specs has been tested and proves to be functioning, test another 12V 1.24mA power supply to keep with the functioning scanner.
3. Make sure the scanner is unlocked (not all scanner have locks). If the scanner has a lock, it functions to block the power outlet and must be slid to the side in order to allow a power supply to be plugged in.
4. Plug into the USB port of the computer and power up the scanner
5. Start xsane
6. If xsane does not find any devices, wait a minute and try again (sometimes the scanner needs to warm up first).
7. If xsane does find a device, it will open a preview pane. Put in an image to scan. (a magazine cover with both text and pictures is good.)
8. Preview and then scan the image.
9. Look for color variations, wavy lines, empty scan lines. The most frequent problem is blotchy weird color. Some scanners miss lines, which will show up as black streaks on the resulting image (best seen at high resolution).

If the scanner fails at any point, record the number and put the scanner in the CBM bin.

If the scanner passes the tests, then write "OK" and the highest dpi tested on the label.

Tested OK scanners can be sent to the Thrift Store or used for Hardware Grants.

SCSI

The following are preliminary notes

• a scsi card is now installed which will work with scanners
• use "scsiadd -s" to look for the scanner
• use "scsiadd -a <id>" to add the device
• there is probably a way of deleting devices no longer being used
• check for the device being used (e.g. /dev/sg0)
• make sure the device is usable by members of the scsi group
  • "chgrp scanner <device>"
  • "chmod 660 <device>"
  • this has already been done for /dev/sg0
• run xsane and follow similar criteria to USB

Parallel

These are not being tested at the moment