Symbol PDT 7200 Series, Справочное руководство

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5-11
Operating the Terminal
Scan the Entire Bar Code Symbol
!
The larger the symbol, the farther away you should hold the scanner to permit the
raster pattern to cover the symbol (but not more than 8 inches). See
Appendix A,
Specifications for more details on the 1-D/PDF417 Scan Element Decode Zones.
!
Hold the scanner close for denser symbols (not less than 2 inches).
!
In all cases, make sure the scan pattern extends at least 3/4 inch beyond each edge of
the bar code (
Figure 5-4 ).
!
The PDF417 bar code symbol has multiple rows, but the raster pattern also has
multiple scanning rows. For this reason, as you scan:
"
Center the aiming pattern on the bar code, as illustrated in Figure 5-3 .
"
Keep the pattern in the same horizontal plane as the bar code.
Figure 5-4. Orienting Scanning Pattern On PDF417 Bar Code
"
If the vertical scan pattern is not high enough to cover a “tall” PDF417 symbol,
move the scanner slowly down toward the bottom of the symbol, keeping the
beam horizontal to the rows, and then slowly back upward toward the top
(
Figure 5-5 ).
3/4” 3/4”