Monarch Instrument 9403TM - Manual (Page 18)

8. If you do not have a verifier or scanner, check the bar code
visually. A bar code that is in spec will have complete bars
and clear spaces. Small alphanumeric characters will look
complete. A bar code that is in spec may not look as good
as one that is too dark, but it will have the highest scan rate.
9. If your print quality is not satisfactory, adjust your print
contrast. See Chapter 6, "Setting the Contrast."
10. Download another label. If the print contrast is still not
satisfactory, call Technical Support.
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