8 Mar
2007
8 Mar
'07
8:05 p.m.
Somehow I got subscribed to an optics catalog. This got me to thinking.
How hard would it be to cause a laser beam to sweep with the speed and
accuracy to be a substitute for a CRT? The upshot? Take an old terminal
with nasty screen burn. Cut off the gun end of the bottle, clean off the
old phosphor. Apply new phosphor of some kind, then mount the laser
rasteriser where the old gun was. Projecting raster images on the side of
a building would be fun too.
--
David Griffith
dgriffi at cs.csubak.edu
A: Because it fouls the order in which people normally read text.
Q: Why is top-posting such a bad thing?
A: Top-posting.
Q: What is the most annoying thing in e-mail?
8 Mar
8 Mar
8:15 p.m.
--- David Griffith <dgriffi at cs.csubak.edu> wrote:
Somehow I got subscribed to an optics catalog. This
got me to thinking.
How hard would it be to cause a laser beam to sweep
with the speed and
accuracy to be a substitute for a CRT? The upshot?
Take an old terminal
with nasty screen burn. Cut off the gun end of the
bottle, clean off the
old phosphor. Apply new phosphor of some kind, then
mount the laser
rasteriser where the old gun was. Projecting raster
images on the side of
a building would be fun too.
That would be pretty cool. The easy part would be to
pulse the laser with the video signal. I have no idea
how one would be able to conveniently scan the laser
across any kind of surface. The electron gun in a CRT
is magnetically deflected. A laser, being totally
optic, would neesd to be mechanically or reflectively
deflected. Also, due to the nasty "laser-ness" of a
laser, I definitely wouldn't want to be in front of a
computer terminal retrofitted with a laser diode. For
projection, however, it would be a neat hack. You'd
have to devise some sort of system of spinning
mirrors, like in the scanner of a laser printer. Maybe
a spinning mirror and a spinning lens...
-Ian
11:57 p.m.
On 8 Mar 2007 at 17:15, Mr Ian Primus wrote:
A laser, being totally
optic, would neesd to be mechanically or reflectively
deflected. Also, due to the nasty "laser-ness" of a
laser, I definitely wouldn't want to be in front of a
computer terminal retrofitted with a laser diode. For
projection, however, it would be a neat hack. You'd
have to devise some sort of system of spinning
mirrors, like in the scanner of a laser printer. Maybe
a spinning mirror and a spinning lens...
Google "laser MEMS video display".
Cheers,
Chuck
8:16 p.m.
Somehow I got subscribed to an optics catalog. This
got me to
thinking. How hard would it be to cause a laser beam to sweep with
the speed and accuracy to be a substitute for a CRT?
Quite easy. Barcode scanners do it regularly in one dimension; you
just need to add another, much slower, scan in the other dimension....
How hard would it be to do it affordably, safely, etc? That's another
question. Note that horizontal scan frequences in the high tens of KHz
are common; you'll have to be scanning something like that fast on the
"fast" axis. Given (say) a 20-faced mirror spinner (which might be
good enough, though it might prove not linear enough), a scan rate of
80KHz (what the display I'm using right now is doing) means this
thing's RPM would be 80,000 (scans/sec) * 60 (sec/min) / 20 (scans/rev)
= 240,000. 240K RPM is pretty bleedin' fast! Perhaps you can find a
video card that can do something like 1024x768 at 20? Most video cards
are concerned with achieving high, not low, refresh rates....
Does anyone know of any electrically controlled optical deflection
technology that has sub-microsecond reaction times? I seem to recall
seeing that some crystals change their refractive index with applied
voltage; if I'm not misremembering, and if they change fast enough,
that might do.
I'd actually prefer to use such a thing not as a raster display, but as
a vector display - hence the interest in electrically deflecting the
beam. I'd like to play vector videogames on a big white wall - either
classic games under something like MAME, or my own....
The upshot? Take an old terminal with nasty screen
burn. Cut off
the gun end of the bottle, clean off the old phosphor. Apply new
phosphor of some kind, then mount the laser rasteriser where the old
gun was.
Neat idea.
Projecting raster images on the side of a building
would be fun too.
But you'd need to crank the laser intensity way up. Even then it might
not be usable except at night. :)
/~\ The ASCII der Mouse
\ / Ribbon Campaign
X Against HTML mouse at rodents.montreal.qc.ca
/ \ Email! 7D C8 61 52 5D E7 2D 39 4E F1 31 3E E8 B3 27 4B
8:53 p.m.
On Thu, 8 Mar 2007, der Mouse wrote:
Mount a prism horizontal and perpendicular to the target in a gizmo that
"rolls" the prism. How hard would the timing on that be?
Using such a thing in daylight would be rather pointless. It definitely
would be usable at night. Think about laser shows.
--
David Griffith
dgriffi at cs.csubak.edu
A: Because it fouls the order in which people normally read text.
Q: Why is top-posting such a bad thing?
A: Top-posting.
Q: What is the most annoying thing in e-mail?
Somehow I got
subscribed to an optics catalog. This got me to
thinking. How hard would it be to cause a laser beam to sweep with
the speed and accuracy to be a substitute for a CRT?
Quite easy. Barcode scanners do it regularly in one dimension; you
just need to add another, much slower, scan in the other dimension.... Does anyone know of any electrically controlled
optical deflection
technology that has sub-microsecond reaction times? I seem to recall
seeing that some crystals change their refractive index with applied
voltage; if I'm not misremembering, and if they change fast enough,
that might do.
I think I saw something like that in the catalog.
I'd actually prefer to use such a thing not as a
raster display, but as
a vector display - hence the interest in electrically deflecting the
beam. I'd like to play vector videogames on a big white wall - either
classic games under something like MAME, or my own....
Yes, I'm interested in doing that too. There's a guy who came up with a
fork of MAME and some hardware for doing this. It was called "Laser
MAME". I don't know what its status is now.
Projecting
raster images on the side of a building would be fun too.
But you'd need to crank the laser intensity way up. Even then it might
not be usable except at night. :) 
9:23 p.m.
Hi,
High BW laser deflection is often done with "Bragg cells". They are
acousto-optic.
You input signals at NN Mc. and the cell essentially changes its
refractive index. As beam shines through, it is deflected.
Not inexpensive. When you design a display for human use, psychopyhsics
very important.
You need to think about energy/unit time, deflection, persistence,
retinal sensitivity, etc.
Many clever people spent their lives working on phosphors.
Sooner or later you get back to Farnsworth and Logie-Baird equivalents.
Back when much of the stuff on this list was new, there was a project
involving 30 Mc. BW laser deflection for writing directly on wafer.
Not sure of current speeds, BW, but bound to be faster.
BR,
Steve
ionder Mouse wrote:
Somehow I got
subscribed to an optics catalog. This got me to
thinking. How hard would it be to cause a laser beam to sweep with
the speed and accuracy to be a substitute for a CRT?
Quite easy. Barcode scanners do it regularly in one dimension; you
just need to add another, much slower, scan in the other dimension....
How hard would it be to do it affordably, safely, etc? That's another
question. Note that horizontal scan frequences in the high tens of KHz
are common; you'll have to be scanning something like that fast on the
"fast" axis. Given (say) a 20-faced mirror spinner (which might be
good enough, though it might prove not linear enough), a scan rate of
80KHz (what the display I'm using right now is doing) means this
thing's RPM would be 80,000 (scans/sec) * 60 (sec/min) / 20 (scans/rev)
= 240,000. 240K RPM is pretty bleedin' fast! Perhaps you can find a
video card that can do something like 1024x768 at 20? Most video cards
are concerned with achieving high, not low, refresh rates....
Does anyone know of any electrically controlled optical deflection
technology that has sub-microsecond reaction times? I seem to recall
seeing that some crystals change their refractive index with applied
voltage; if I'm not misremembering, and if they change fast enough,
that might do.
I'd actually prefer to use such a thing not as a raster display, but as
a vector display - hence the interest in electrically deflecting the
beam. I'd like to play vector videogames on a big white wall - either
classic games under something like MAME, or my own....
The upshot? Take an old terminal with nasty
screen burn. Cut off
the gun end of the bottle, clean off the old phosphor. Apply new
phosphor of some kind, then mount the laser rasteriser where the old
gun was.
Neat idea.
Projecting raster images on the side of a building
would be fun too.
But you'd need to crank the laser intensity way up. Even then it might
not be usable except at night. :)
/~\ The ASCII der Mouse
\ / Ribbon Campaign
X Against HTML mouse at rodents.montreal.qc.ca
/ \ Email! 7D C8 61 52 5D E7 2D 39 4E F1 31 3E E8 B3 27 4B
8:27 p.m.
rasteriser where the old gun was. Projecting raster
images on the side of
a building would be fun too.
I must admit, I rather like the idea of projecting a terminal screen onto a
wall... A 80x25 terminal that is 5' or wider could be fun! :^) Then hook
it up to a PDP-11 and play Pacman on it. :^) For some strange reason kids
don't seem to be impressed by running a Pacman clone on a PDP-11 and
displaying it on a VT420. But if you project it on the side of a large
building... :^)
Zane
11:02 p.m.
At 05:05 PM 3/8/2007 -0800, you wrote:
Somehow I got subscribed to an optics catalog. This
got me to thinking.
How hard would it be to cause a laser beam to sweep with the speed and
accuracy to be a substitute for a CRT? The upshot? Take an old terminal
with nasty screen burn. Cut off the gun end of the bottle, clean off the
old phosphor. Apply new phosphor of some kind, then mount the laser
rasteriser where the old gun was. Projecting raster images on the side of
a building would be fun too.
You'd have to make sure you can modulate the beam. After all, if you're
going to draw unconnected shapes with it, you have to be able to turn the
beam off. Now you're talking about a very low duty cycle. How do you get
enough brightness to see it? Sounds like a pretty powerful laser.
-----
619. [Alcohol] Why is American beer served cold? So you can tell it from
urine.
--David Moulton
--... ...-- -.. . -. ----. --.- --.- -...
tpeters at nospam.mixcom.com (remove "nospam") N9QQB (amateur radio)
"HEY YOU" (loud shouting) WEB: http://www.mixweb.com/tpeters
43? 7' 17.2" N by 88? 6' 28.9" W, Elevation 815', Grid Square
EN53wc
WAN/LAN/Telcom Analyst, Tech Writer, MCP, CCNA, Registered Linux User 385531
9 Mar
9 Mar
9:28 a.m.
From: Fred Cisin <cisin at xenosoft.com>
Reply-To: "General Discussion: On-Topic Posts Only" <cctech at
classiccmp.org>
To: "General Discussion: On-Topic and Off-Topic Posts"
<cctalk at classiccmp.org>
Subject: Re: raster laser?
Date: Thu, 8 Mar 2007 20:28:30 -0800 (PST)
Downtown Las Vegas, the real vegas (get off the strip!) they are projected
every night on a canopy screen over the street.
There are several companies that make cheapie x-y servo mirrors and software
for the pc too to create vector laser displays.. Surf for it, or give me a
few minutes and I will find them.
I did raster laser to make 3d models by sintering layers of plastic powder.
Later sold to Goodyear. But thats another story.
Randy
_________________________________________________________________
Find a local pizza place, movie theater, and more?.then map the best route!
http://maps.live.com/?icid=hmtag1&FORM=MGAC01
Projecting raster images on the side of a
building would be fun too.
In Las Vegas there are occasionally laser graphics over a considerable
distance onto sides of buildings. But always vector graphics.
9:50 a.m.
Randy Dawson wrote:
Downtown Las Vegas, the real vegas (get off the
strip!) they are
projected every night on a canopy screen over the street.
There are several companies that make cheapie x-y servo mirrors and
software for the pc too to create vector laser displays.. Surf for it,
or give me a few minutes and I will find them.
I did raster laser to make 3d models by sintering layers of plastic
powder. Later sold to Goodyear. But thats another story.
You're not talking about the Fremont Street Experience, are you? If so,
those aren't projections. That's a massively multi-element LED screen.
Peace... Sridhar
2:55 p.m.
> > Projecting raster images on the side of a
building would be fun too.
>
>In Las Vegas there are occasionally laser graphics over a considerable
>distance onto sides of buildings. But always vector graphics.
On Fri, 9 Mar 2007, Randy Dawson wrote:
Downtown Las Vegas, the real vegas (get off the
strip!) they are projected
every night on a canopy screen over the street.
great stuff, but short range projection
some of the projection onto buildings on the strip, particularly during
Comdex, was from over a mile away
There are several companies that make cheapie x-y
servo mirrors and software
for the pc too to create vector laser displays.. Surf for it, or give me a
few minutes and I will find them.
I did raster laser to make 3d models by sintering layers of plastic powder.
Later sold to Goodyear. But thats another story.
would like to hear more
12:06 a.m.
Hmmmm, sounds the making for either a new episode of Myth Busters, or
Jackass III - all depends how it turns out and how many people are
blinded or maimed in the process ;-)
Curt
David Griffith wrote:
Somehow I got subscribed to an optics catalog. This
got me to thinking.
How hard would it be to cause a laser beam to sweep with the speed and
accuracy to be a substitute for a CRT? The upshot? Take an old terminal
with nasty screen burn. Cut off the gun end of the bottle, clean off the
old phosphor. Apply new phosphor of some kind, then mount the laser
rasteriser where the old gun was. Projecting raster images on the side of
a building would be fun too.
2:28 p.m.
World's Best Product Warning Label Ever:
"WARNING: DO NOT LOOK INTO LASER WITH REMAINING GOOD EYE!"
Can't help chuckling every time I think of that.
-T
At 12:06 AM 3/9/2007 -0500, you wrote:
Hmmmm, sounds the making for either a new episode of
Myth Busters, or
Jackass III - all depends how it turns out and how many people are blinded
or maimed in the process ;-)
Curt
David Griffith wrote:
Somehow I got subscribed to an optics catalog.
This got me to thinking.
How hard would it be to cause a laser beam to sweep with the speed and
accuracy to be a substitute for a CRT? The upshot? Take an old terminal
with nasty screen burn. Cut off the gun end of the bottle, clean off the
old phosphor. Apply new phosphor of some kind, then mount the laser
rasteriser where the old gun was. Projecting raster images on the side of
a building would be fun too.
-----
226. [Commentary] ...nothing banned in Singapore can be all bad. --Cosma R.
Shalizi, on The Economist
--... ...-- -.. . -. ----. --.- --.- -...
tpeters at nospam.mixcom.com (remove "nospam") N9QQB (amateur radio)
"HEY YOU" (loud shouting) WEB: http://www.mixweb.com/tpeters
43? 7' 17.2" N by 88? 6' 28.9" W, Elevation 815', Grid Square
EN53wc
WAN/LAN/Telcom Analyst, Tech Writer, MCP, CCNA, Registered Linux User 385531 
12:01 p.m.
And thusly were the wise words spake by David Griffith
Somehow I got subscribed to an optics catalog. This got me to thinking.
How hard would it be to cause a laser beam to sweep with the speed and
accuracy to be a substitute for a CRT? The upshot? Take an old terminal
with nasty screen burn. Cut off the gun end of the bottle, clean off the
old phosphor. Apply new phosphor of some kind, then mount the laser
rasteriser where the old gun was. Projecting raster images on the side of
a building would be fun too.
I would rather do vector graphics.. :) I have seen plans on the where
you use the voice coils from two old hard drives with mirrors stuck to
them to bounce the laser onto a wall..
Cheers,
Bryan
2:32 p.m.
At 12:01 PM 3/9/2007 -0500, you wrote:
And thusly were the wise words spake by David Griffith
It was somewhere about 1980 that I built the basic high-power car-audio
speaker laser deflector. Mine used plastic ball-socket pivots and aluminum
stock as levers, to pivot a speaker horizontally. The laser goes from that
mirror to another one driven vertically by a second speaker.
I have a Real Laser (plasma tube NeHe) to drive it. Still works.
Haven't we all built something like that at one time or another?
-----
481. [Humor] Shouldn't the Psychic Friends call you? --heard on the radio
--... ...-- -.. . -. ----. --.- --.- -...
tpeters at nospam.mixcom.com (remove "nospam") N9QQB (amateur radio)
"HEY YOU" (loud shouting) WEB: http://www.mixweb.com/tpeters
43? 7' 17.2" N by 88? 6' 28.9" W, Elevation 815', Grid Square
EN53wc
WAN/LAN/Telcom Analyst, Tech Writer, MCP, CCNA, Registered Linux User 385531
Somehow I got subscribed to an optics catalog. This got me to thinking.
How hard would it be to cause a laser beam to sweep with the speed and
accuracy to be a substitute for a CRT? The upshot? Take an old terminal
with nasty screen burn. Cut off the gun end of the bottle, clean off the
old phosphor. Apply new phosphor of some kind, then mount the laser
rasteriser where the old gun was. Projecting raster images on the side of
a building would be fun too.
I would rather do vector graphics.. :) I have seen plans on the where
you use the voice coils from two old hard drives with mirrors stuck to
them to bounce the laser onto a wall..
2:56 p.m.
Popular Electronics had a lissajous figure generator project to attach to a
scope in XY mode. Just a couple of slowly frequency and amplitude ramping
sine wave oscillators. I always wanted to drive some XY servo mirrors and
put that on the wall for a laser light show.
My XY mirrors came out of an old Pioneer laser disk player. (HeNe tube
too!) They would swing several degrees, with the mirrors mounted on a voice
coil like yoke over a magnet.
Randy
From: Tom Peters <tpeters at mixcom.com>
Reply-To: "General Discussion: On-Topic and Off-Topic
Posts"<cctalk at classiccmp.org>
To: "General Discussion: On-Topic and Off-Topic Posts"
<cctalk at classiccmp.org>
Subject: Re: raster laser?
Date: Fri, 09 Mar 2007 13:32:13 -0600
At 12:01 PM 3/9/2007 -0500, you wrote:
_________________________________________________________________
Mortgage rates as low as 4.625% - Refinance $150,000 loan for $579 a month.
Intro*Terms
https://www2.nextag.com/goto.jsp?product=100000035&url=%2fst.jsp&tm…
And thusly were the wise words spake by David
Griffith
It was somewhere about 1980 that I built the basic high-power car-audio
speaker laser deflector. Mine used plastic ball-socket pivots and aluminum
stock as levers, to pivot a speaker horizontally. The laser goes from that
mirror to another one driven vertically by a second speaker.
I have a Real Laser (plasma tube NeHe) to drive it. Still works.
Haven't we all built something like that at one time or another?
-----
481. [Humor] Shouldn't the Psychic Friends call you? --heard on the radio
--... ...-- -.. . -. ----. --.- --.- -...
tpeters at nospam.mixcom.com (remove "nospam") N9QQB (amateur radio)
"HEY YOU" (loud shouting) WEB: http://www.mixweb.com/tpeters
43? 7' 17.2" N by 88? 6' 28.9" W, Elevation 815', Grid Square
EN53wc
WAN/LAN/Telcom Analyst, Tech Writer, MCP, CCNA, Registered Linux User
385531
Somehow I got subscribed to an optics catalog. This got me to
thinking.
How hard would it be to cause a laser beam to
sweep with the speed and
accuracy to be a substitute for a CRT? The upshot? Take an old
terminal
with nasty screen burn. Cut off the gun end of
the bottle, clean off
the
old phosphor. Apply new phosphor of some kind,
then mount the laser
rasteriser where the old gun was. Projecting raster images on the side
of
a building would be fun too.
I would rather do vector graphics.. :) I have seen plans on the where
you use the voice coils from two old hard drives with mirrors stuck to
them to bounce the laser onto a wall.. 
3:17 p.m.
Randy Dawson wrote:
Popular Electronics had a lissajous figure generator
project to attach
to a scope in XY mode. Just a couple of slowly frequency and amplitude
ramping sine wave oscillators. I always wanted to drive some XY servo
mirrors and put that on the wall for a laser light show.
My XY mirrors came out of an old Pioneer laser disk player. (HeNe tube
too!) They would swing several degrees, with the mirrors mounted on a
voice coil like yoke over a magnet.
Randy
My girlfriend bought me a laser lissajous figure toy thing about a week
ago, by some odd synchronicity.
It has two angled mirrors spun by little motors, and you can change the
speed and direction to draw various patterns.
Gordon
4:50 p.m.
Randy Dawson wrote:
Popular Electronics had a lissajous figure generator project to attach
to a scope in XY mode. Just a couple of slowly frequency and amplitude
ramping sine wave oscillators. I always wanted to drive some XY servo
mirrors and put that on the wall for a laser light show.
Doesn't Helmholtz show a rig like this in his "On the Sensations of
Tone" (circa 1863)? No lasers (not even incandescent light), but a
mechanical mirror-equipped rig to look at Lissajous figures.
Oscillographs are much older than electronics.
Cheers,
Chuck
10 Mar
10 Mar
12:18 a.m.
OK Chuck.
We can take a look at the Scientific American Ameteur Scientist.
Its online somewhere, or I'll look up the article for those iterested.
L.C. Stong did an article on an XY swinging pendulum, adjustable XY rates.
knife edges and a funnel filled with a pencil thin stream of sand to drop
onto black paper.
Hows that for old as dirt?
Cheers,
Randy
From: "Chuck Guzis" <cclist at
sydex.com>
Reply-To: "General Discussion: On-Topic and Off-Topic
Posts"<cctalk at classiccmp.org>
To: "General Discussion: On-Topic and Off-Topic Posts"
<cctalk at classiccmp.org>
Subject: Re: raster laser?
Date: Fri, 09 Mar 2007 13:50:05 -0800
_________________________________________________________________
Find what you need at prices you?ll love. Compare products and save at MSN?
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Randy Dawson wrote:
Popular Electronics had a lissajous figure generator project to attach
to a scope in XY mode. Just a couple of slowly frequency and amplitude
ramping sine wave oscillators. I always wanted to drive some XY servo
mirrors and put that on the wall for a laser light show.
Doesn't Helmholtz show a rig like this in his "On the Sensations of
Tone" (circa 1863)? No lasers (not even incandescent light), but a
mechanical mirror-equipped rig to look at Lissajous figures.
Oscillographs are much older than electronics.
Cheers,
Chuck
12:37 a.m.
On 3/10/07, Randy Dawson <rdawson16 at hotmail.com> wrote:
OK Chuck.
We can take a look at the Scientific American Ameteur Scientist.
I have that series of articles somewhere in a reprint collection - how
to build nitrogen CO2 lasers and tunable dye lasers from scratch, then
how to make holograms and lissajous patterns with modified speakers
and function generators. I always wanted to build the lissajous rig,
but never got past the component collecting stage. These days, with
the ubiquity of laser levels and laser pointers, that's the cheap end
of the project (I bought a laser level at the grocery store last month
for $5, then pulled the lens out of it so it projects a spot, not a
line, now. I was going to use it for a one-way RS-232 link, but it'll
make a nice lissajous source).
Just add Pink Floyd. ;-)
-ethan
4:53 p.m.
New subject: raster laser? / Sci. American
Ethan Dicks wrote:
On 3/10/07, Randy Dawson <rdawson16 at hotmail.com> wrote:
Aug 1980, page 158, sounds like the second article you refer to:
attaching mirrors to two speakers oriented at angles to each other, etc.
(The same issue has an opened disk drive on the cover and an article about
disk drive technology.)
OK Chuck.
We can take a look at the Scientific American Ameteur Scientist.
I have that series of articles somewhere in a reprint collection - how
to build nitrogen CO2 lasers and tunable dye lasers from scratch, then
how to make holograms and lissajous patterns with modified speakers
and function generators. I always wanted to build the lissajous rig,
but never got past the component collecting stage. These days, with
5:20 p.m.
New subject: raster laser? / Sci. American
On 3/10/07, Brent Hilpert <hilpert at cs.ubc.ca> wrote:
Ethan Dicks wrote:
Aug 1980, page 158, sounds like the second article you refer to:
attaching mirrors to two speakers oriented at angles to each other, etc.
(The same issue has an opened disk drive on the cover and an article about
disk drive technology.)
That sounds entirely familiar for the original, but the specific
publication I'm thinking of is a 5mm-thick soft-bound book containing
a dozen articles/projects about lasers - generating coherent light and
using coherent light.
I don't have the publication in front of me or I'd cite chapter and
verse. Thanks for the reference to what was probably the original
article. These days, one could whip up some software for a sound card
to generate the functions, or one could even write a program to make
an audio file, then let an iPod play back the X and the Y waveforms as
left and right channel ;-)
-ethan
12:40 a.m.
On 3/10/07, Randy Dawson <rdawson16 at hotmail.com> wrote:
OK Chuck.
We can take a look at the Scientific American Ameteur Scientist.
Its online somewhere, or I'll look up the article for those iterested.
Does anyone on the list have this collection (SciAm Amateur Scientist
columns on CD-ROM)?
http://www.ercb.com/brief/brief.0248.html
I never knew they put them together on one set of disks. That'll take
quite a while to read cover to cover.
-ethan
2:39 a.m.
On Mar 10, 2007, at 12:40 AM, Ethan Dicks wrote:
I have them...I ordered them the day they were announced.
-Dave
--
Dave McGuire
Port Charlotte, FL
OK Chuck.
We can take a look at the Scientific American Ameteur Scientist.
Its online somewhere, or I'll look up the article for those
iterested.
Does anyone on the list have this collection (SciAm Amateur Scientist
columns on CD-ROM)? 
8:12 a.m.
New subject: raster laser? - Ameteur Scientist
Dave McGuire wrote:
They are available on ePay for $24.00
Bob
Does anyone on the list have this collection (SciAm Amateur Scientist
columns on CD-ROM)?
I have them...I ordered them the day they were announced.
-Dave
--Dave McGuire
Port Charlotte, FL
11:32 a.m.
New subject: Scientific American (was raster laser?)
On Sat, 10 Mar 2007, Ethan Dicks wrote:
Does anyone on the list have this collection (SciAm
Amateur Scientist
columns on CD-ROM)?
http://www.ercb.com/brief/brief.0248.html
I do. I got mine from:
http://www.surplusshed.com/pages/item/m2071.html
Price is $24.00.
Mike Loewen mloewen at cpumagic.scol.pa.us
Old Technology http://ripsaw.cac.psu.edu/~mloewen/Oldtech/
1:10 a.m.
On 9 Mar 2007 at 23:18, Randy Dawson wrote:
Hows that for old as dirt?
I wasn't being facetious; one thing that struck me when I read the
Helmholtz work was his drawings of waveforms and even spectra of
sound waves. Very accurate; but how did he get them in 1863?
Some of the equipment was darned clever.
http://physics.kenyon.edu/EarlyApparatus/Rudolf_Koenig_Apparatus/Vibra
tion_Microscope/Vibration_Microscope.html
Lissajous figures date from about 1815:
http://physics.kenyon.edu/EarlyApparatus/Oscillations_and_Waves/Lissaj
ous_Figures/Lissajous_Figures.html
Cheers,
Chuck
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