On 26 Jan 2010 06:31:04 GMT, DoN. Nichols wrote:
On 2010-01-25, Frnak McKenney wrote:
On 25 Jan 2010 05:28:54 GMT, DoN. Nichols wrote:
[ ... ]
[...]
That is, what kind of projects led you to
think that you needed -- or simply had a use for -- that test
equipment?
I had been experimenting with components form stripped down
discarded equipment for a long time, and would occasionally try to build
something -- and needed a way of assuring that the components were as
marked, and the voltages were near what was expected.
You know, I never thought about that aspect of it. I could always
use my father's Simpson analog multimeter (as long as he was at work
or on a railfan trip). I just had to be very careful to put things
away exactly where I found them... and with three brothers,
"plausible deniability" was fairly easy.grin!
O.K. My parents did have any test equipment at all -- and only
a couple of tiny claw hammers with one claw broken off each. :-)
(I'll assume that was a "didn't".)
So you had to carry all your projects to the local TV repair shop,
six miles through the snow and uphill both ways? grin!
[ ... ]
[...]
All wiyht. Rho sritched mg kegtops awound?
Hmm ... a reminder of another useful habit of the geek/scrounger
type. When dealing with rebooting everything, I had to lift the
keyboard for the firewall down from the top of the rack, and it disloged
a Cenco "Lab Jack" which fell corner first on the Sun keyboard which
switches between the Mac Mini and the Sun Fire 280R (Rack mount server
version of the Sun Blade 1000/2000).
Ouch!
I know the feeling. I think I need to build a robot that is smart
enough to move my cup of tea a second or two _before_ my forearm
knocks it over onto my desk. (Did you notice the 10-minute gap in
my typing? grin!)
... It totally destroyed the keycap
for "Page Down" -- so I went to the peanut can full of keycaps from
another keyboard of the same construction, and a bit of digging through
found the proper replacement key cap. Just a bit lighter in color. :-)
Luckily, the keyswitch below it survived, and it was just the key cap.
I've had to disassemble some of these keyboards and take the flexible
printed circuits and other parts down to the shop and use compressed air
to remove the accumulation of cat hair which had worked between the
layers.
So you were able to finally justify the twenty-odd keyboards in
various states of disrepair that had been cluttering up your
basement for the past ten years? (Sorry -- thinking about my own
basement, not yours. grin!)
But seriously... if you're interested in an overpriced and
generally impractical solution to your Damaged Keytop Problem, a
solution that would suck up _hours_ of your time, check out the
latest issue of "Make" magazine (v21, January 2010); its theme is
"Your Desktop Factory: 3D Manufacturing at Home".
Here's what you would do:
1) Build the SplineScan "DIY 3D Scanner" from p.54
2) Find an indentically-shaped keytop. If it's a specially-shaped
Enter key, glue and sand the broken one; if you can't find all
the pieces, patch it with wax or plaster.
3) Scan the keytop.
4) Use the scanned model to create a 3D model.
5) Create a replacement keytop using a 3D plotter like the
mis-named "CupCake CNC" device from MakerBot described on p.46,
or one of a number of similar gadgets described on assorted 'web
sites.
6) Sand, drill, letter, and paint the result.
But here's the "leverage" part: if you post your 3D model on a
publicly accessible site, the next person with a broken Sun keyboard
can skip steps 1-4, since he only has to download your model.
If you think about it, this is a marvelous way for manufacturers to
save on parts inventory, the ultimate JIT method for keeping a huge
number of plastic parts readily available for decades (or even
centuries -- "You, Too Can Build Your Own 2059 Edsel!"). The only
ongoing expenses are the 3D printer, "toner", a stack of read-only
32Gb SD chips, and someone to do the lookup and kick off the machine
as required.
Oh, and someone to collect the money. grin!
Seriously, I realise that you can't cost-justify such a setup to
replace one broken keytop, any more than you can justify building
even a 78RPM phonograph disc cutter and a playback unit simply to
make a permanent copy of your child's first word, even if it's
something as world-shattering as "photosynthesis". But... record a
thousand songs and make it possible for others to listen to music
whenever they want, and you've created an entire industry.
You should be able to pick up a copy of Make v21 at Borders or
Barnes&Noble, or check their 'web site at
www.makezine.com.
* * *
Jumping back to long-snipped digression in this thread, a discussion
which might even have been with you -- pencil-drawn resistors -- the
other day I stumbled on a DIY project called "DrawDIO!" that
actually _uses_ this effect as a part of yet another re-invention of
the Theremin:
http://www.ladyada.net/make/drawdio/
The circuit is, like most really good ideas, simple enough once you
know the secret: a 555 multivibrator controlled by pencil-drawn
lines. What I found most impressive was the number of different ways
people had found to _use_ the device. I think someone earlier in
this thread felt that creativity required manual dexterity; see if
you agree after viewing the video clips showing the DrawDIO off.
Frank
--
I can explain it to you, but I can't understand it for you.
--
Frank McKenney, McKenney Associates
Richmond, Virginia / (804) 320-4887
Munged E-mail: frank uscore mckenney ayut mined spring dawt cahm (y'all)