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Take care not to disturb the positioning of the sensor or damage the sensor assembly while the wand tip is off for cleaning.
After cleaning the aperture and sensor window, the tip should be gently and securely screwed back into the wand.
3. Store the wand in a clean, dry place. Static electricity could damage the wand's circuitry.
4. Always turn off the HP-41C before inserting or removing the wand interface module. Failure to do so could damage both the
calculator and the wand.
Do not insert your fingers or any objects other than an HP module or plug-in accessory into any port. To do so could alter the
Continuous Memory or damage the port of the calculator. Always keep the port caps in place over any module ports you are not
currently using.
A Word About Bar Code
Bar code is a combination of bars and spaces formatted to represent various types of information. Three parameters that help
determine readability are contrast ratio between the bars and spaces, space width, and wear or print quality of the bars. Because the
use of color in bar code can reduce the contrast ratio between bars and spaces, it is recommended that you use only black bar code
printed on white surfaces. Error in space width can result from the distortion introduced to some degree by most copying machines.
Depending upon the degree of distortion present, this may noticeably affect the bar code you copy. Your copies should have a narrow
bar width and spacing of no less than 15 mils. Wear of poor print quality may introduce frequent errors and can render the bar code
unreadable. Here are some examples of worn bar code and bar code of poor print quality.
Copying Bar Code
Most typical office copiers do not reproduce bar code well. Poor bar resolution, reduced bar width, and stray marks are the most
frequently encountered problems. These problems can be minimized by using a copier that produces a very dark image with sharp
resolution. When copying bar code label materials, it is best to use a machine with a ''pasteup'' mode to avoid reproducing the edges
of the labels on the copy. The wand may detect such images and produce an error condition. In most cases, reliable copies cannot be
made from other copies.
As you may have noticed, the photo mechanisms in copy machines move in either side-to-side or top-to-bottom motion. The
sharpness of resolution in your copies of bar code may vary with the direction of this motion across the originals you copy from. If
the bars in your copies are not sharply defined, try copying the material with the originals turned 90° on the copy surface. If the copier
you have access to does not reproduce bar code well, you may want to try the alternative of having your bar code reproduced through
an offset printing process.
Protecting Bar Code
When scanning bar code, remember that the wand should be used with a light touch. Applying pressure only increases wear. Because
most bar code will wear rapidly if unprotected, you should always cover bar code you are scanning with one of the transparent sheets
provided with the wand. Another method of protecting bar code is to cover it permanently with a non-glossy, transparent adhesive
tape. If bar code you are using becomes smeared, creased, or smudged, it should be replaced.
Improper Wand Operation
If the HP-41C operates, but fails to respond properly when you scan bar code, do the following:
HP 82153A - Wand Owner Manual - page 24
CAUTION
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