Symbol PDT 7500 Series Product Reference Manual page 56

PDT 7500 Series Product Reference Guide for DOS
The scanner has successfully decoded the symbol when the green LED lights and you hear a
short, high tone beep.
Scan the Entire Bar Code Symbol
The larger the symbol, the farther away you should hold the scanner to permit the
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raster pattern to cover the symbol (but not more than 8 inches). See the 1-D/PDF417
Scan Element Decode Zones.
Hold the scanner close for denser symbols (not less than 2 inches).
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In all cases, make sure the scan pattern extends at least 3/4 inch beyond each edge of
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the bar code (Figure 4-4).
The PDF417 bar code symbol has multiple rows, but the raster pattern also has
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multiple scanning rows. For this reason, do three basic things as you scan:
" Center the aiming pattern on the bar code, as illustrated before.
" Keep the pattern in the same horizontal plane as the bar code.
3/4"
Figure 4-4. 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 4-5).
4-10
3/4"