E13B Calibration Document - Xerox 6100BD - Phaser Color Laser Printer Fundamentals

Quality control

E13B calibration document

6-4
MICR signal strength is the only magnetic specification in ANSI
standards. Magnetic testers are needed to identify magnetic
versus non-magnetic extraneous ink, and they can be useful in
interpreting waveform uniformity issues. All other standards use
optical dimensions and require optical or visual inspection.
MICR quality decisions cannot be based solely on magnetic test
equipment without regard to ANSI standard conformance
requirements. Refer to "Signal strength," later in this chapter, for
information on signal strength test specifications.
NOTE: Due to calibration, design, and manufacturing
differences, signal strength readings from MICR testers vary to
some degree, even when they are set up correctly and in
calibration. These differences are caused partly by the different
MICR characteristics of the printing technology that is used and
partly by the magnetic read and write head design. If the test
equipment is not in correct calibration, there are very large
differences.
The E13B calibration document is used to determine if the MICR
tester is measuring the signal correctly. It provides a printed
MICR character (On-Us symbol) calibrated by the manufacturer.
The MICR character signal value, read by the master MICR
reader, has been written in the space provided (see the following
figure). All good calibration documents have the notation "WCC,"
reflecting calibration to the most recent ANSl standard.
Calibration documents without this notation should not be used
until their accuracy can be checked against a known good
document.
Generic MICR Fundamentals Guide