hack a digitizer pen [** EDIT: PICS, 648K **]

[tarvoke]

EDIT:

so the mp200 arrived, and worked just fine with the x61t (no eraser, no pressure sensitivity; as expected)

and then it got its poor self vivisected....

the short version is: holding the pcb and 3 bits of the nib assembly together between my fingers (oh lordy that was tricky, maybe I should have just used cello tape hahaha) the pen does function properly but the length of the assembly seems prohibitive in mounting it to some sort of finger ring -- might as well leave the pen intact and glue it to a ring. if we knew what sort of circuit to construct (I suppose I could get out the multimeter and probe this sucker up) then manufacturing a smaller more convenient size would be possible.

here's the long version:

shot 1: pen intact (nib off-camera on the right side), button removed. you can see the button's switch, and two potentiometers. I imagine the pots are for fine tuning the coil's 2 states: button up (default state), button down (click).

http://tintar.com/mp200/pa130170.jpg

shot 2: coil that is at the tip of the pen (nib butts up against this, you'll see in next shots)

http://tintar.com/mp200/pa130173.jpg

shot 3: guts and all. I opened the pen by peeling away light grey plastic that was covering the back/clip end of the pen. eventually the dark grey end pulled loose and I was able to pull out the little pcb "tray" which seems mainly to consist of the 2 pots, bunch of smd resistors, and the aforementioned coil.

http://tintar.com/mp200/pa130177.jpg

shot 4: closer on the pcb package.

http://tintar.com/mp200/pa130178.jpg

shot 5: close up on the (cheap, non-replaceable!) nib. the nib slots into a little cylinder of black plastic, which in turn slots into a tiny rubber o-ring. I guess this allows a little "give" or physical feedback? it did not seem to make for pressure sensitivity, but I could be wrong. I imagine the ibm and higher quality 3rd party pens have much different construction of the nib.

http://tintar.com/mp200/pa130179.jpg

20 bucks spent, curiosity somewhat satisfied. hrm.

/EDIT

I've read that the x4 and x6 pens are compatible with each other's screens (altho not necessarily the actual storage slot) -- so an active digitizer pen from e.g. a usb tablet should also work yes?

so: assuming it is a wacom digitizer, there is a magnetic field resonantly coupled with the pen, i.e. it powers the pen and also reacts to it. correct?

so: what exactly is it in the pen? small coil? rfid tag? I am curious to try getting a cheap (wacom-compatible) digitizer pen and taking it apart, to get out the whatsis, and, say make a small ring (or other fastening method) to wear it on my fingertip. don't care particularly about the extra button function at this point, just the main simple pointing/tapping bit.

anyone tried something like this before? suggestions?

Note from Moderator: Thanks for the warning, but images should be < 50k.

[joester]

Once you've dismantled it and removed the whatsis from the dohickey, go to the music store and (possibly swallowing your pride a bit) inform them you want to look at banjo picks.

They are usually a soft steel and can be soldered to, making a means of mounting a bracket somewhat easy. It all depends on your McGuyver abilities. They also fit onto the end of your finger quite comfortably. So much in fact, you might find yourself considering a banjo purchase.

Well, maybe not that last part, but the pick would work well.

Joe

[proaudioguy]

I like the banjo pick idea. Maybe just mount the whole pen to the banjo pick, or maybe just the bottom half, excluding the eraser.

[new2tablet]

I've thought about it many times. An accurate Saga multitouch. There are two components to the pen: sensing and activation. You'll notice that until you put pressure on the pen tip (compress a small spring which probably has an embedded switch) the cursor will follow your movement but won't select angthing. So, the finger nib mast have the spring... I've tried other Wacom pens on my x60. No sensing. Good luck and if you take apart a Pen, please send us pictures.

[tarvoke]

the fingerpick is a great idea, agreed.

I was not sure what the deal was with clicking/tapping -- figured it might be proximity related. but a switch makes much more sense. also makes this idea a bit more difficult to produce.

checking just now, either it is an extremely light spring or no spring at all and just a very small movement of the nib.

I didn't want to spend $40-60 on a new ibm pen just to destroy it haha. the friend who owns the machine is nervous that she'll lose or break the pen she already has (really, a product of this price and market should come with a measly extra pen!)

will keep looking for cheap 3rd party wacom type pens, although it's rather disheartening to hear that they may not work after all.

[tarvoke]

ok looks like wacom's branding for this particular digitizer is penabled (*groan*)

the cheapest thing I see out there is replacements for a "penabled" acer tablet, this pen seems fairly basic (1 button but no eraser) and runs about $15.

[tarvoke]

just adding a little more info (found here: http://mobilepcwiki.org/mpc/index.php?title=Wacom and here: http://www.tabletpcbuzz.com/forum/topic ... 543#148566 )

pens that work:
artpad II
cintiq15
cintiq18
cross executive
other vendor penabled tablet pc

wacom pens that do not work:
cintiq21
graphire
intuos

in that same thread linked above, there was also this
per Wacom, some of their pens have nibs that are too hard for a tabletPC. I think that one of the pens that I discussed with them was the UP801E, so before you buy it, or any other pen not specifically labeled as being TabletPC suitable

[tarvoke]

well, I ordered an mp200 pen (I think this is the same slim/basic one sold as a direct replacement for acer tablet and a couple other vendors)

assuming it works normally on the x61, I'll be getting out the razor knife and do some surgeries...

[tarvoke]

*bumpity*
(edits made to first post of thread)

[draco2527]

Awesome! Thank for the pics; I myself always wanted to know as well what they looked like inside...but at ~$50 each...no way.

I guess there goes the "finger" option, that is as large as the pen; never would have imagined...

That is one large coil as well!! I guess the pen needs more "juice"
than I thought.

I know Toshiba makes a "compact" version to go in the underside of the M200 in case you loose your primary pen ( Ironic because before I bought the spare pen (when I had their Tablet) I would misplace my stylus all the time; after I purchased the spare it never happened!! Go Figure!)

The Toshiba "spare" has limited functionality in comparison to the primary pen but that might be an option for the "finger stylus"

[zaimek]

I had previously an Acer TPC which came with both a normal size pen and this smaller mb200. In the bigger one it was very easy to take out the eraser part which woudl do for 'clicking and tapping'. It was way shorter than mb200, a bt fatter though.