Hand Held Products Quick Check 200 Series User Manual page 24

[ - Tests - >]
Pressing the Scroll [<>]Button once at this point will access the area of the
QC200's programming where test procedures are determined. Use of the Select
[0] and Scroll [<>] buttons here will allow you to select the unit's pass/fail level
criteria (Traditional vs. ANSI), use of a higher level of statistical accuracy for
measurement of each scan path (NormalAccur vs. ExtendAccur), type of
Decodability calculation to use (Avg DMargin vs. Decodability) and whether,
when ANSI is the pass/fail criteria, letter or number grading is used (Ltr. Grades
vs. Num. Grades). An explanation of these possible selections follow.
"Trad'l P/F" vs. "ANSI PrQual> A" / "ANSI PrQual> B"/ "ANSI PrQual?
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C"/"ANSI PrQual> D" The Quick Check 200 Series can apply Pass/Fail
criteria based on either the "Traditional" bar code print tolerances and PCS
measurements or the "Graded" methodology specified in the ANSI Standard "Bar
Code Print Quality – Guideline" X3.182. Upon any measurement scan, the
QC200 beeps either once to indicate a passing symbol or three (3) times to
indicate failure of one or more tests. Choose here whether to apply Traditional
Pass/Fail criteria -- PCS value and Print Tolerances – or the graded <A> through
<F> criteria and scales from ANSI's Print Quality Guideline.
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"NormalAccur" vs. "ExtendAccur" The Quick Check 200 Series is capable of
scanning in a "Normal Accuracy" mode as well as in "Extended Accuracy". In the
"Extended Accuracy" Mode, ALL individual parameter measurements and results
are averaged over eight (8) successive scans of a given scan path of the symbol
under test, greatly reducing reading variability due to variations in scanning
motion and minor scan path variations. This is not to be confused with ANSI's
recommended ten (10) scan symbol average, where ten (10) individual symbol
scans have their final scan grade averaged.
"Avg DMargin" vs. "Decodability" "Decodability" is an ANSI graded measure
of how close a given scan comes to a reference decode failure due to variations
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in the bar and/or space widths. The Quick Check 200 Series has the ability to
analyze a symbol using "Decodability Margin" (Avg DMargin in the QC200) as
well as true "ANSI" Decodability (Decodability in the QC200). "Decodability
Margin" is the character-averaged value of Decodability. Decodability is what
percentage of the symbology's safe decoding margin is left for the scanner after
printing errors. Lower margin values and corresponding lower grades indicate an
increased susceptibility to decoding failure due to scanning errors such as, for
example, acceleration or bar or space size deviations. NOTE: Variations in scan
speed affects ANSI Decodability. When hand scanning set this option to "Avg
DMargin". "Decodability" (ANSI Decodability) should only be used by those
who have a very consistent and smooth scanning action or with automated
scanning. The QC200 will "measure" your scanning and prompt you to "Scan
Faster", "Scan Slower" or "Scan Evenly" if it detects gross variations in your scan
rates.
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