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CN80 Preliminary Test Results

We got a couple of demo CN80 computers from Honeywell and were surprised by the results of some of the testing we put it through.

The first is the range of the radio. Normally, we’d see a Honeywell reader drop off the network at when it got 350 to 400 feet away from an access point. We were able to get over 700 feet away with the CN80. We repeated the test with an old Cisco 1242 access point (802.11g only) to see if it was beam forming that accounted for the extended range, but we got the same results with the old access point. This will be of great interest to anyone who has an outdoor wireless network.

The second surprising result was the standard range 2D scanner, which uses the Honeywell N6603ER engine. We enabled DPM mode and it read most of our DPM samples as well, if not better than dedicated DPM scanners. It’s performance was very impressive.

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Avoid Interleaved 2 of 5 Code

I was asked to recommend a scanner by a customer who sent me samples of their bar codes. They were all Interleaved 2 of 5 code, which is a numeric only code whose only saving grace is that you can print a lot of digits in a small space. Here are three symbologies encoding the numbers 1 to 8:

You can see that Interleaved 2 of 5 takes up the least space, but Code 128 is pretty close. Interleaved 2 of 5 has a built in defect in that the stop/stop patterns are not unique and if the scanner enters or leaves the code in a spot that resembles a start or stop, the code can be short scanned.

Code 128 is always printed with a check digit anyway and has a unique start/stop pattern, making it a superior code to I 2 of 5.

My customer’s bar code looked like this:

This is a picture from our microscope. Notice that the narrow bar measures .1 mm, or 3 mils. This is a 300 dpi printer. The wide to narrow ration of this code should be 3 to 1; this is printed at 4 to 1. Lastly, the narrow bar under the red arrow should be one element wide, this one is two.

Their printer is doing a bad job printing this code, but fortunately for them modern scanners are pretty forgiving and this code can be read reliably with a Xenon with high density optics.

 

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PM series printer real time clock

All PM series printers have real time clocks in them. They become functional when a battery is inserted in the printer’s motherboard. You’ll have to remove the cover to access this; the PM43c battery slot looks like this:

The printer’s display will show the date and time if a battery is installed.

Only printers configured with 802.11 WiFi boards can be ordered with a battery installed from the factory. You can order the battery separately, part number 318-051-001 , but they are a standard battery that you can get anywhere:

In the newer firmware you can also configure the printer to contact a time server to synch its clock. Select Wizards, Calibration, Date & Time from the main to enable the time server.

If your printer can’t be connected to the Internet you can sill use the real time clock by manually setting the date and time using the Wizard or the System settings.

NB: When you set the time manually make sure that you use GMT time, not your local time. There’s a bug in the firmware that will change the clock setting according to the time zone and DST settings when the printer’s power is cycled after the clock is set.