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Hand-Drawn Barcodes for the HP41
01-29-2018, 09:35 AM (This post was last modified: 01-29-2018 09:41 AM by damaltor.)
Post: #1
Hand-Drawn Barcodes for the HP41
Hi everybody,

i finally got a barcode wand now. The previous owner sent to me the wand itself, the manual and the paper keyboard, the stickers are obviously missing after the years. Thats fine by me, because it is fairly easy to make your own.

What caught my attention: Together with the paper keyboard he sent me a small sheet of barcodes for the X-Function Module, which are obviously hand-drawn. I am fairly sure that this is an original document becuase you can see faint pencil streaks above and below the codes which seem to be erased after drawing, and under a microscope you can somewhat see the overlapping parts of the "thick" lines which were drawn with the same pen as the thin lines, they are simply 4 lines next to each other with a slight overlap to make it one thick line.

has someone seen something similar before? Was Hand-drawing barcodes a thing back then?

[Image: pc.jpg]
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01-29-2018, 12:42 PM
Post: #2
RE: Hand-Drawn Barcodes for the HP41
(01-29-2018 09:35 AM)damaltor Wrote:  Hi everybody,

i finally got a barcode wand now. The previous owner sent to me the wand itself, the manual and the paper keyboard, the stickers are obviously missing after the years. Thats fine by me, because it is fairly easy to make your own.

What caught my attention: Together with the paper keyboard he sent me a small sheet of barcodes for the X-Function Module, which are obviously hand-drawn. I am fairly sure that this is an original document becuase you can see faint pencil streaks above and below the codes which seem to be erased after drawing, and under a microscope you can somewhat see the overlapping parts of the "thick" lines which were drawn with the same pen as the thin lines, they are simply 4 lines next to each other with a slight overlap to make it one thick line.

has someone seen something similar before? Was Hand-drawing barcodes a thing back then?

[Image: pc.jpg]

Wow! Someone must have had a lot of time on their hands! Do they scan in OK?
Back then, we didn't have laser or inkjet printers and most 8- or 9-pin dot matrix printers couldn't reproduce the bar codes accurately enough to scan in without error. 24-pin dot matrix printers could but it took a while.

Tom L
Cui bono?
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01-29-2018, 01:04 PM
Post: #3
RE: Hand-Drawn Barcodes for the HP41
Yes, thed do actually scan fine. Probably not as perfect as printed ones would, but usually they work on the first try.

nowadays, with laser printers, printing the barcodes is fairly easy, though every barcode generator behaves differently, especially with XROM functions and Alpha-Append characters and the label markers. the hard part now is to generate valid codes, not the printing anymore.
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01-29-2018, 01:07 PM
Post: #4
RE: Hand-Drawn Barcodes for the HP41
That was real dedication to draw those. Back when the barcode wand was released, I wrote a program for the 9825 at the lab where I worked to draw barcodes on the 9872 plotter. We used a modified drafting pen and balanced it with a small weight on a screw so that the 9872's pen mechanism could raise and lower it. I avoided damaging the nib from repeated landings on the paper by drawing them with a connected line along one edge. That setup worked really well and made nice looking barcode.
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01-29-2018, 01:10 PM
Post: #5
RE: Hand-Drawn Barcodes for the HP41
Wow, that sounds interesting. Any chance you still have some of them to scan?

Also: Dedication -> lots of it in that piece of paper. There is not a single correction on any of those barcodes, so it seems like whoever did that drew them all at once without errors. i wonder how long that took (and how often he/she started over).
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01-29-2018, 02:23 PM (This post was last modified: 01-29-2018 05:52 PM by 4ster.)
Post: #6
RE: Hand-Drawn Barcodes for the HP41
I have a couple of programs by Edward M. Keefe that I purchased from the user's library "back then". They aid in creating barcode with a technical pen and a custom guide built from two rulers which he documented in the program listing form. I never did it, but the procedure looked workable with reasonable drafting skills. He stated in the documentation that a line of code takes about 15 minutes to create. It is worth noting that while he demonstrated some good looking hand drawn code, the barcode to scan the 130 and 220 line programs were NOT hand drawn!

"Back then" I made my own bar code with the 82162A printer and the plotter module if I felt documenting a program with bar code was worth cutting down a tree to make the miles of 8 inch strips required. And I recently added to my collection a 7470 plotter which makes beautiful code with refillable plotter pens. (I am simple minded and enjoy watching a pen plotter draw.)

Steve
In order of appearance: HP 41CV, CMT-MCGPS, HP 41CX, DM 41, DM 42
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01-29-2018, 02:48 PM
Post: #7
RE: Hand-Drawn Barcodes for the HP41
Who would not enjoy that?

i acquired a casio pb-700 a long while ago which has a tiny four-color plotter module which nicely fits into a suitcase. it is stunning to whatch it draw or even write texts with it tiny four pens.

http://www.bitsndust.com/en/2013/09/casio-pb-770/
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01-29-2018, 04:19 PM
Post: #8
RE: Hand-Drawn Barcodes for the HP41
Is it possible that someone who didn't have access to a copying machine placed this paper on top of a printed barcode program and traced over it with a pencil to make their own copy?
It seems unlikely someone could produce a working barcode freehand without using a working one as a tracing template.
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01-29-2018, 04:28 PM
Post: #9
RE: Hand-Drawn Barcodes for the HP41
(01-29-2018 04:19 PM)Steve Simpkin Wrote:  Is it possible that someone who didn't have access to a copying machine placed this paper on top of a printed barcode program and traced over it with a pencil to make their own copy?
It seems unlikely someone could produce a working barcode freehand without using a working one as a tracing template.

I do not think so as the paper the barcodes are on is very thick and opaque.
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01-29-2018, 05:08 PM (This post was last modified: 01-29-2018 05:16 PM by 4ster.)
Post: #10
RE: Hand-Drawn Barcodes for the HP41
(01-29-2018 04:19 PM)Steve Simpkin Wrote:  Is it possible that someone who didn't have access to a copying machine placed this paper on top of a printed barcode program and traced over it with a pencil to make their own copy?
It seems unlikely someone could produce a working barcode freehand without using a working one as a tracing template.

I think with Keefe's method you could create the bar code in the original post from scratch.

As I understand the procedure Keefe outlined, first one created an ink template of uniform narrow bars and spaces with his custom ruler. Below the template the artist marks with pencil the narrow bars with an "I". The location of a wide bar was marked with an "X", with the top of the X linking two narrow bars. His program helped determine the location of the "I"s and "X"s in the line of bar code. The artist now fills in the spaces above the X's to make wide bars. The pencil marks can be erased to make the code look neater when photocopying.

From the original post it sounds like a similar procedure was used.

Steve
In order of appearance: HP 41CV, CMT-MCGPS, HP 41CX, DM 41, DM 42
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01-29-2018, 06:13 PM
Post: #11
RE: Hand-Drawn Barcodes for the HP41
Hi,
1980 was the heyday for barcode experimentation and I was hand-drawing barcodes with a fine-point felt-tip black marker for a good part of that year. It bore lots of fruit, and the result was lots of activity in the PPC Journal - check issues starting with Volume 7 Number 5 (from June 1980). Ultimately, a home-made BASIC program for the HP 9845 desktop computer enabled printing HP-41 barcodes on its 80-column thermal printer and that simplified experimentation a great deal. It also was the basis for the barcode page in the back of Bill Wickes' "Synthetic Programming on the HP-41C" tome (also known as the "Green Book").

Jake Schwartz
PPC member $1820
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01-30-2018, 04:29 AM
Post: #12
RE: Hand-Drawn Barcodes for the HP41
(01-29-2018 01:10 PM)damaltor Wrote:  Wow, that sounds interesting. Any chance you still have some of them to scan?

I don't have any of the resulting barcode output, as I didn't have the barcode wand myself, but I have acquired a couple of 9825Ts and a couple of 9872Cs, and could conceivably recreate something similar if I make a reverse engineered 98228 ROM so I have a way to save HPL programs.
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01-30-2018, 04:44 AM
Post: #13
RE: Hand-Drawn Barcodes for the HP41
(01-30-2018 04:29 AM)cruff Wrote:  [quote='damaltor' pid='89950' dateline='1517231428']
... if I make a reverse engineered 98228 ROM so I have a way to save HPL programs.
Off topic but you might want to consider the reverse engineered SSS Mass Storage it is much more flexible.

Paul.
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03-21-2018, 11:15 PM
Post: #14
RE: Hand-Drawn Barcodes for the HP41
Back in the 80s I got a Wand from UPLE (Users Program Library, Europe) as a reward for submitting a bunch of programs to the library.

So I was trying to find a way to print barcodes. Eventually I found out that the computing lab had a Diablo daisywheel printer in the machine room for high quality copies and got permission to use it.

The barcodes produced where a bit narrow, but quite usable, especially when using the TITAN-10 daisywheel which had a tall | character.

The way to print barcodes was to set the daisywheel character spacing to almost nothing, and print about 10 | characters for a narrow bar and double that for a wide bar.

Clearly to print a line of program barcode, the printer would hammer away like a machine gun.

So the first time the operators tried to print one of my test bar codes, they had the scare of their life. Eventually they had me supply a sample with each print run, so that they would know what to expect.

:-)

**vp
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03-22-2018, 08:53 AM
Post: #15
RE: Hand-Drawn Barcodes for the HP41
There are Fonts with barcodes instead of letters in them that can be printed, at least there is the one I did, I think it was 2 of 5, it's been a while. I draw it with FontForge, very nice program.
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03-22-2018, 10:36 AM
Post: #16
RE: Hand-Drawn Barcodes for the HP41
Getting a wand as reward for submitting programs. Nowadays you get a lawsuit when you point out severe security problems...

the good old times Sad
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