Does anyone in AppleFritter land have any info, schematic, photos, etc. of the old Apple Graphics Tablet Interface Card STYLUS?
I'm looking specifically for information pertaining to the Stylus itself. I have the Tablet and interface card but am missing the Stylus for it.
I know it has a coil (inside the pen) and possible other circuitry, but I don't have any details for it.
I want to make up a pen that will work with the tablet. Found a good readable schematic of the Tablet's interface board here: Apple ][ Graphic Tablet Schematic
Based on the circuitry, there's an input to an Op-Amp that appears to be from a coil type arrangement, but there is also a transistor acting like some form of gated switch that is also triggered by something from within the Pen.
Does anyone have photos of the pen's internals they can share, possible a schematic, and (potentially) obtain an ohm reading of the internal coil?
If I can get this information, I think I can succesfully make a stylus. Thank you all in advance.
Apple Graphics Tablet View 1
Apple Graphics Tablet View 2
I wanted to buy that, but, it went over the price that I was willing to pay for something that would spend most of its life in a box on a shelf, as I do not expect to be doing CAD on the ][+.
I would imagine that the pen itself is a small coil though.
More here: http://quartdepomme.fr/quartdepomme/Hardware_Apple_for_Apple_II/Pages/A2M0029_Apple_II_Graphics_Tablet.html
I'm looking for the manual, as I would partly suspect the pen specs to be disclosed in it.
Major eye candy Tom... I did a little research on the pen, though I can't verify, but it appears the pen has metal pieces (shapes) in it with 3 wires attached to specific elements.
My initial thought was that it might have a coil... (I guess my thoughts on how they detect row & column was a bit skewed from how they actually do it)
Is there any info on the pen itself? I found some patients but they don't show the inside very clearly. Thanks for posting BTW. Nice looking hardware you've got there.
Graphics Tablet Operation and Reference Manual
Graphics Tablet Technical Procedures
The user manual has a schematic in Apx E, although the scan quality is not as good as it could be. It is on one page, at the end of the book. The tech notes describe differences in the RFI and non-RFI version.
Thanks for posting this info. Still looking for information on the Pen by itself.
Schematic below will print out on 11 x 17 Paper. Likely the cleanest one you'll find.
Right-click to "View Image" for actual size view.
Apple Graphics Tablet Interface Card Schematic.jpg
After reading an article of history of 1979 Tablets here: https://tedium.co/2017/09/21/wacom-tablet-history/ I noted the mention of
the Summagraphics Bitpad. The article states "the Apple Graphics Tablet was a rebranded Bitpad ", so I took a shot on eBay to see what
might be available, and out of sheer luck there were 3 available which include the Stylus! Lucky for me, I now have a way to restore
this tablet to OEM condition. For those interested, see item # 361263348487 . Take note this is for the tablet & Pen only and does NOT
include an apple compatible card. The Summagraphics Bitpad is actually a serial interface sevice. The parts used and the case design in
this tablet are similar.
So, for all you folks with Apple Graphics tablets that need parts, here is a potential source for you to get what you need.
I must mention that I have not received this yet, so no guarantees. More on thsi when I receive the actual device.
Nice info. Now we need a clone of the interface and we can all have one. Heheh.
That aside, what do ou plan to do with the beastie?
Like most of my Apple ][ items, I want to make sure it's all working with the documents and software. Beyond that and after trying it out for a while, it will go into storage like all the other Apple ][ hardware I have.
It's not like I can do anything really meaningful with it.
Kinda fits into the same category of the other Apple ][ items I have in the collection.
I am after all, an Apple ][ collector. All will eventually be handed off or sold to the next collector.
I just hope my kids don't view it as junk and toss it when I'm gone. =:-O
If anyone in AppleFritter land is able to take a close-up photo of the Molex connector at the end of the Stylus that shows the wire colors, it would be greatly appreciated.
Does anyone have the Utopia Graphics System software they can share? Supposed to work well with this Graphics Tablet.
Thank you in advance.
Did the stylus from the Bitpad work for you? I recently purchased an Apple Graphics Tablet that came with the manual and original software. However, I'm missing both the stylus and the interface card.
The stylus will work, but without the interface card, it is a paperweight.
I have an image of Utopia Graphics Tablet System, but no manual. I don't speak English, couldn't figure out how to use it, but the software definitely works. There are some pictures below. Maybe someone has an instruction manual? Thanks in advance!
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Instructions for the Utopia Graphics Tablet System.
https://www.applefritter.com/files/2021/05/26/Utopia%20Graphics%20Tablet%20System.pdf
Edited link - Tom
A gem of a scan and disk post. Thanks for making it freely available for me (and all) to enjoy.
I've been an Apple Graphics Tablet user since the first Rev 0 version from 1979 along with the Summagraphics BitPad One. I have two Rev 0 tablets and one Rev 1, two working tablet interface cards but only one Apple stylus and one BitPad One stylus.
Apple contracted with Summa to make a version of the BitPad One for Apple. The tablets are very similar in construction and electro-mechanical operation but differ in their eletronics interfaces. As mentioned in an earlier post the BitPad utilizes a RS-232 serial interface while the Apple tablet utilizes a proprietary 8 bit interface to the Apple II/II+/IIe/IIgs backplane slots. Both use pen styluses that use the magnetorestrictive waveguide principle but they are not directly interchangable without modification. Both varients have an inductor and resistor along with copper foil shielding inside the pen. I have both of these tablets and have compared them. Their stylus resistors have different values. The Summa stylus has a 470K 5% resistor and a 12.1 uH inductor. The Apple tablet stylus utilizes a 10K resistor. The Apple's pen has a 1M resistor but I have not measured its coil inductance yet.
I do know of someone who tried substituting a BitPad One stylus without modification with the Apple's tablet interface card but it did not work for one reason or another.
I have photos of the stylus and a schematic that I can make available to those interested.
airnocker
I meant to mention that the Apple's pen stylus's inductance measures 38uH. I'd attach a schematic but I do not see a way to attach a jpg file.You can attach files using the "Media Browser". Upload the file in the first screen, and continue clicking "Next" until all options have been set.
Correction: it has a 10K resistor. Both styli have a spring-loaded, normally open push button switch that is closed when pressing the stylus tip down. And with apologies, even with a htm or html image file I see no way to insert or add it into a forum comment.
Thanks for the suggestion. That was the magic "key".
AppleTabletStylusSchematic-0.jpg
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The Graphics Tablet Pen needed a low frequency shielded cable for the pickup coil and an extra wire for the switch. A stereo audio cable would probably have been a pretty good choice but they didn't exist yet so Rod Holt had the cable manufacturer build an unusual cable, he had them use insulated wire for some of the shield strands and these insulated shield strands were used to carry the switch signal. Clever solution, a buried signal wire with very little disturbance of the cable.
Thanks for your additional comment. One side of the pickup coil was soldered to the low frequency, adhesive copper shield, that in turn tied to the single-conductor, shielded cable's shield wire which then connected to pin 3 (circuit ground) of the Molex connector. The other side of the coil connected to an enamel coated single conductor wire (somewhere I have its guage size in inches and/or mm) that ran under the thin copper shields and connected to the center conductor of the shielded cable that tied to pin 4 of the Molex connector. One side of the PB switch was also tied to the braided shield. The other side of the PB switch connects to the 10K resistor whose other end connects to pin 1 of the Molex connector.
Here is a magnified photo of the pen's tip. You can just see the bulge from one of the coil wires at about the 9 o'clock position emerging and traveling up under the copper foil. The coil surrounds the ball-point pen type stylus and is buried in black epoxy or molded into the plastic tip area.
AppleStylusTip-1.jpg