Hand Held Products 600, 800 manual Calculating, To review the dimensional parameters

W/N Ratio

The wide-to-narrow ratio (W/N) applies to symbologies with two element widths including Code 39, Interleaved 2 of 5 and USS-Codabar. W/N is not meaningful for the other symbologies and is not displayed. When measured, the W/N value is compared against generic or user-specified limits appropriate for the symbology. If the W/N Ratio is within these limits, it is rated OK! or pass. If the W/N Ratio is outside these limits (HI! or LO!) this test fails.

Decodability

Decodability is the percentage of the symbology’s safe decoding margin available for the scanner after printing errors. Lower margin values and corresponding lower grades indicate an increased susceptibility to decoding failure due to scanning errors.

Scanning variations such as acceleration can cause bar or space deviations due to uneven, too fast or too slow scanning and provide lower margin values. You can set the type of decodability in the test criteria options to either ISO/IEC Decodability or character averaged decodability (Avg). With either calculation method, the decodability is rated A if > .62, B if > .50, C if > .37,

D if > .25 or F if < .25.

•ISO/IEC Decodability is a graded measure of how close a given scan comes to reference decode failure due to variations in bar and/or space widths.

•Character averaged decodability is also called “D margin.”

♦To review the dimensional parameters:

1. Scan a symbol.

2.If the cursor is not next to Dim, use the arrows to place it there. The first two dimensional parameters appear in the results line.

3.To view other dimensional parameters, press ↓.

The names of the dimensional parameters and their results scroll.

4.To review other types of data (Ref or Fmt), press →.

OR

5.To resume scanning, start at the quiet zone and scan the symbol.

Calculating X

The total shown as the dimensional parameter is the total symbol width in “X” dimension terms. Formally, a bar code symbol’s width includes the quiet zones. The value presented as total is a calculated count of the number of “X” dimensions from the starting bar through the ending bar of the scanned symbol. You can use this value and manually measure the symbol’s actual width to calculate “X.”

1.Press SELECT to display the menu with the term Print Results on top.

2.Press ↓ to move the cursor next to Calculate “X”.

4 - 10 Quick Check® 600/800 Series User’s Guide