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 1.25A (1,250mA) positive center power supply, but there are many exceptions.
     • It can be helpful to mark a 12V 1.25A 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 1.25A specs has been tested and proves to be functioning, test another 12V 1.24A 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 the USB cord from the computer into the USB port of the scanner and plug in the power supply.
5. Click on the "K" on the menu bar and scroll up to Xsane.
6. Start xsane.
7. Xsane will either find the scanner and open up a preview pane or it will tell you that a device has not been found.
8. If xsane does not find any devices, wait a minute and try again (sometimes the scanner needs to warm up first) .
   • Close Xsane, unplug the USB and plug it back in and open Xsane again.
   • If Xsane still finds no device, the scanner is not functioning or Linux does not support the scanner.
     • To make sure that Linux supports the scanner. Look on sane-project.org in a web-browser.
       • Click on "Supported devices." Then under "Sane Development (CVS) Version," click on "Ordered by Manufacturer." Browse the listed devices to ensure that the scanner which is being tested is supported.
       • If the scanner is supported, this probably means that the scanner is not functioning. Mark an "X" over the scanner's ID # and write the number on the Tally sheet under Recycle. Take the scanner to the Gaylords, to the CBM bin in order to recycle it.
       • If the scanner is not supported, set scanner aside with a note on the ID# so that it may be tested on another system.
9. If xsane finds a device, it will open a preview pane. Put in an image to scan. (a magazine cover with both text and pictures is good.)
   • Click preview to scan the image.
   • 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).
   • Alter the resolution to a higher number and scan the image to further test the scanner.

If the scanner fails at any point, record the number on the Tally sheet, place an "X" through the ID # and put the scanner in the CBM bin.

If the scanner passes the tests, then write "OK" on the ID # sticker and the highest dpi (dots per square inch - resolution) tested on the label.

Tested OK scanners can be sent to the Thrift Store or used for Hardware Grants. Place the OK scanners on a shelf with a piece of paper indicating the destination of the scanner. Be sure to keep a functioning power supply with the OK scanners.

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