Chip with simple program for Toy

Rich The Philosophizer · Nov 21, 2004

On Sat, 20 Nov 2004 15:25:49 -0800, dB wrote:

Someone wrote:

Just because something is accepted, does _not_ make it correct.

and

That, now as ever, is the ONLY valid test of correctness.

The motoring world and its granny "accepts" exeeding the speed limit.

And someone else wrote about dam and damn. The latter is a
contraction of damnation.

No, it is not. A damn is an individual thing, like an apple. You could
give a damn, or you could give two damns. But you can't give one or two
dmanations. That's more of a cumulative noun, like dishwater. You can't
have one dishwater or two dishwaters, but you could have _some_ dishwater.
And you could have some damnation, but not one or two. Of course, there's
damnation as a state of being, which damn as a verb is intended to consign
the recipient to, but that's a different meaning entirely.

Hope This Helps!

;^j
Rich

Clarence · Nov 21, 2004

"dB" <dmb06851@yahoo.com> wrote in message
news:1757808.0411201525.92af131@posting.google.com...

Someone wrote:
snip

And someone else wrote about dam and damn. The latter is a
contraction of damnation.

Not really:

5 entries found for damnation.
damˇnaˇtion ( P ) Pronunciation Key (dm-nshn)

n. The act of damning or the condition of being damned.

1. Condemnation to everlasting punishment; doom.
2. Everlasting punishment.
3. Failure or ruination incurred by adverse criticism.

No references to a contraction under either definition.

Robert Monsen · Nov 22, 2004

CBarn24050 wrote:

Subject: Re: Resonance
From: Robert Monsen rcsurname@comcast.net
Date: 21/11/04 19:50 GMT Standard Time
Message-id: <ok6od.649997$8_6.899@attbi_s04

The Phantom wrote:

On 20 Nov 2004 22:48:45 GMT, cbarn24050@aol.com (CBarn24050) wrote:

Subject: Resonance
From: daksoy@gmail.com (Deniz)
Date: 20/11/2004 22:04 GMT Standard Time
Message-id: <2502fe80.0411201404.3fc06c24@posting.google.com

My first question is: At resonance frequency wo, can we immediately
(without calculating time dependent expressions) say that when the
stored energy in the capacitor reaches maximum, the stored energy in
the inductor becomes 0 ?

NO, the enrgy in both components are equal but opposite.

What does it mean for the capacitor and inductor to have opposite
energies?

At any given time, they don't have 'opposite' energy, because energy is
a scalar value.

However, the energy that they have is passed back and forth between the
two elements; thus, when the capacitor has maximal energy, the inductor
has minimal energy.

You could say that the energy for each is a sinusoidal wave above the x
axis, 180' out of phase, and that the sum of the two sine waves is equal
to the total energy in the system. That energy can be increasing if
there is an impulse, decreasing if the oscillation is damped, or
'constant' if the damping and impulse balance out.

--
Regards,
Robert Monsen

"Your Highness, I have no need of this hypothesis."
- Pierre Laplace (1749-1827), to Napoleon,
on why his works on celestial mechanics make no mention of God.

Perhaps not the best choice of words, i'll try again. These components are
reactive so there is no energy as such, ie it's not real energy. It does not go
from 1 to the other and back again. When I said that they equal but opposite,
what I meant was that they allways add up to zero at any time in the cycle.

I dont' want to put you on the spot, but I think there is energy stored
in resonant systems. Look at the film of the tacoma narrows bridge being
torn apart due to resonant oscillations. Each little nudge from the wind
stores more energy in the resonant system, until it collapses.

And, in electrical systems, the energy does go from the inductor to the
capacitor and back again. At any point, the energy stored in a capacitor is

Uc = 1/2 C * V^2

the energy stored in an inductor is

Ul = 1/2 L * I^2

Thus, the energy is maximum in the inductor when the current in the
system is maximum, and the energy in the capacitor is maximum when the
voltage across it is maximum. However,

Uc + Ul = U

which is the total energy at a given time, which is what I think you
were trying to say.

This is exactly analogous to a mass and spring system in basic physics,
where the energy goes from kinetic energy to potential energy and back
again.

--
Regards,
Robert Monsen

"Your Highness, I have no need of this hypothesis."
- Pierre Laplace (1749-1827), to Napoleon,
on why his works on celestial mechanics make no mention of God.

The Phantom · Nov 22, 2004

On 22 Nov 2004 00:21:38 GMT, cbarn24050@aol.com (CBarn24050) wrote:

Subject: Re: Resonance
From: Robert Monsen rcsurname@comcast.net
Date: 21/11/04 19:50 GMT Standard Time
Message-id: <ok6od.649997$8_6.899@attbi_s04

The Phantom wrote:
On 20 Nov 2004 22:48:45 GMT, cbarn24050@aol.com (CBarn24050) wrote:

Subject: Resonance
From: daksoy@gmail.com (Deniz)
Date: 20/11/2004 22:04 GMT Standard Time
Message-id: <2502fe80.0411201404.3fc06c24@posting.google.com

My first question is: At resonance frequency wo, can we immediately
(without calculating time dependent expressions) say that when the
stored energy in the capacitor reaches maximum, the stored energy in
the inductor becomes 0 ?

NO, the enrgy in both components are equal but opposite.

What does it mean for the capacitor and inductor to have opposite
energies?

At any given time, they don't have 'opposite' energy, because energy is
a scalar value.

However, the energy that they have is passed back and forth between the
two elements; thus, when the capacitor has maximal energy, the inductor
has minimal energy.

You could say that the energy for each is a sinusoidal wave above the x
axis, 180' out of phase, and that the sum of the two sine waves is equal
to the total energy in the system. That energy can be increasing if
there is an impulse, decreasing if the oscillation is damped, or
'constant' if the damping and impulse balance out.

--
Regards,
Robert Monsen

"Your Highness, I have no need of this hypothesis."
- Pierre Laplace (1749-1827), to Napoleon,
on why his works on celestial mechanics make no mention of God.

Perhaps not the best choice of words, i'll try again. These components are
reactive so there is no energy as such, ie it's not real energy.

When the voltage across a capacitor is greater than zero, is there
not an energy of .5*C*V^2 associated with that capacitor? And
likewise given a current greater than zero in an inductor, is there
not an energy of .5*L*I^2 stored in the inductor? Are these not
*real* energies?

I notice on some of your other posts that you seem to be familiar
with circuit simulators such as Spice. If you simulate the circuit in
the OP's post (I chose C=.01uF, L=25mH and R=1 ohm, for a resonance
freq of 10.066 KHz, and a current source of 1 amp at that freq), and
plot the current in the C and L for about 10 milliseconds, you will
see that as the currents in C and L increase, they stay 180 degrees
out of phase with each other. If you plot .5*C*v^2 and .5*L*i^2 (the
instantaneous power in C and in L), you will see that these quantities
are double frequency sinusoids with a DC component. Let the current
source drive be applied for about 8 milliseconds, then reduced to
zero; plot the *sum* of those instantaneous powers. You will see that
after the 8 milliseconds, the result is very nearly a constant (if you
make R=0 so the Q is infinite, then the sum of the two instantaneous
powers will be dead constant after the current source drive is reduced
to zero). If the current source drive stays on with R=1, it
superimposes a little ripple on the sum of the powers as the stored
energy in C and L ramps up.

(In the low-Q case, where for example, I made R=10k, the sum of the
instantaneous powers is not constant. But that is not the interesting
case.)

So, in fact, (in the infinite-Q case, where R=0) after the current
source drive is turned off, the capacitor and inductor continue to
exchange energy indefinitely. The voltage and current in each are
sinusoids, and the sum of the instantaneous powers is constant. The
law of Conservation of Energy requires this, because without loss
components in the circuit, there is no mechanism for energy to be
lost. The energy is sloshed back and forth between the capacitor and
inductor forever (in the simulator, at least, where it is possible to
have a circuit with R=0, including the wiring and parasitics).

It does not go

from 1 to the other and back again. When I said that they equal but opposite,
what I meant was that they allways add up to zero at any time in the cycle.

John Fields · Nov 22, 2004

On Mon, 22 Nov 2004 04:43:18 GMT, "Don Kelly" <dhky@peeshaw.ca> wrote:
"normanstrong" <normanstrong@comcast.net> wrote

Electricity through a wire is controlled by the size of the wire times
its length. Replacing a 1" section of a 10' piece of 12Ga wire with
18Ga is not at all the same as replacing the entire 10' with 18Ga.

-----------
An I sure hope that the load at the end of the wire is the controlling
factor. I like to get what I pay for in useful work, not losses in the wire.

---
Surely you don't think grocery bags are free...

If not you, who do you think is paying for the losses?

--
John Fields

The Phantom · Nov 23, 2004

On 22 Nov 2004 16:58:20 GMT, cbarn24050@aol.com (CBarn24050) wrote:

Subject: Resonance
From: The Phantom phantom@aol.com
Date: 22/11/2004 13:04 GMT Standard Time
Message-id: <knm3q0dfe1ui7s0715dhghs1ar0ccs0593@4ax.com

When the voltage across a capacitor is greater than zero, is there
not an energy of .5*C*V^2 associated with that capacitor? And
likewise given a current greater than zero in an inductor, is there
not an energy of .5*L*I^2 stored in the inductor? Are these not
*real* energies?

Just because the energy is not real doesn't mean that it does not exist, it's
just the confusing terms (real & imaginary) that apply to complex (but not
complicated) maths. You would think that they would have come up with something
a bit better by now.

I think the problem here is that you are trying to analyze the
problem with the *phasor* representation of the voltages on the L and
C. But the question the OP asked about stored energy cannot be
appropriately dealt with from that point of view. You must analyze
the instantaneous time response of the circuit.

It does not go
from 1 to the other and back again. When I said that they equal but
opposite,
what I meant was that they allways add up to zero at any time in the cycle.

What I should have said was that there is no CHANGE in the total energy level
during the cycle.

This is better than saying they add up to zero, because it allows
for the possibility that the sum is non-zero. But, as I explained in
my long post, it is only when the Q of the circuit is infinite (and
there is no drive from the current source) that there is no change in
the total energy level during one cycle. If the current source drive
is in operation, or if R is non-zero, then the total energy level
varies somewhat during a cycle. This cannot be determined from a
phasor point of view, however.

>

Don Kelly · Nov 23, 2004

"John Fields" <jfields@austininstruments.com> wrote in message
news:2704q0pliv9j8c0tskmqjhgg8bo8irvhiu@4ax.com...

On Mon, 22 Nov 2004 04:43:18 GMT, "Don Kelly" <dhky@peeshaw.ca> wrote:
"normanstrong" <normanstrong@comcast.net> wrote

Electricity through a wire is controlled by the size of the wire times
its length. Replacing a 1" section of a 10' piece of 12Ga wire with
18Ga is not at all the same as replacing the entire 10' with 18Ga.

-----------
An I sure hope that the load at the end of the wire is the controlling
factor. I like to get what I pay for in useful work, not losses in the
wire.

---
Surely you don't think grocery bags are free...

If not you, who do you think is paying for the losses?

--
John Fields
---------

True enough- But I like to minimise those losses. If the wire size is
"controlling the electricity" then the "bag" becomes more expensive than the
stuff in the bag.
--
Don Kelly
dhky@peeshaw.ca
remove the urine to answer

rayjking · Nov 24, 2004

The circuit will work if you add a resistor from base to emitter of all of
the bipolars to allow the zener to reach its test current. usually the test
current is 5-10ma. This is also needs consideration when making the divider.
LM317 and LM339's are popular because of these drawbacks.

Ray

"CBarn24050" <cbarn24050@aol.com> wrote in message
news:20041101034712.16253.00001638@mb-m01.aol.com...

Subject: Re: zener trouble
From: Robert Monsen rcsurname@comcast.net
Date: 01/11/2004 07:28 GMT Standard Time
Message-id: <cAlhd.282869$wV.19497@attbi_s54

Erik Durling wrote:
We're a couple of students doing an electronics project. We are to
construct a battery indicator circuit. We had a finished circuit on
paper and we had simulated it with Multisim 7. But when we tested the
circuit in real life, it didn't work at all like we had planned (or
according to simulation). The circuit was based upon the idea of
zenerdiodes having a constant voltage drop, and not conducting if the
circuit isn't able to supply the needed voltage across it. But the
zener-diodes doesn't stop conducting at all, and the voltage drop is
far from constant.

This is the main circuit: http://ersker.com/circuit.gif

The zener diodes used in real life are: BZX55 and not BZC55, but that
ought not change anything (right?).

We did a DC Transfer Analysis in the simulator and got three nice
curves showing the voltage at the three collectors (compared to
ground) as the voltage from the source goes from 0-4.5 volts, and
everything seems right there: http://ersker.com/dctrans.gif

So, the problem we're having with our real circuit is that the LEDs
never turn off (the transistors are always saturated). The zener
diodes doesn't stop conducting when the voltage across them goes under
their specified value.

What's our mistake/misconception?

Do the zeners only operate correctly at a certain current?

Hi, if you look at the datasheet you will see why it doesn't work. Why you
would even consider simulating such a circiut is beyond me.

Tom MacIntyre · Nov 26, 2004

On Thu, 25 Nov 2004 23:46:52 GMT, Steve Evans
<smevans@jif-lemon.co.mars> wrote:

On Thu, 25 Nov 2004 09:17:29 -0500, John Popelish <jpopelish@rica.net
wrote:

Plot their impedances on log linear paper (logarithmic frequency or
period) and their inverse relationship is obvious. It is the linear
frequency scale that is distorting the ratiometric relationship.

well I wonder why they don't mention that rather important little fact
in the text books!!! :-(

It all depends on the textbook.

Tom

Dmitri(Cabling-Design.com · Nov 29, 2004

Jim Douglas wrote:

Any recommendations for kits, and were to get them for making PC boards
using the resist pen method? I would make 1-3 boards every couple of
months
and they would not be all theat complicated.

Thanks!

JimD

Radio Shack's P/N 276-1576 should do. The board themselves are very thin
in this kit (I think, 0.008), so you may want to buy thicker boards,
depending on your application. The resist pen is included, too. Well, OK,
it's just a Sharpie, but it's there ;-)

--
Dmitri Abaimov, RCDD
http://www.cabling-design.com
Cabling Forum, color codes, pinouts and other useful resources for
premises cabling users and pros
http://www.cabling-design.com/homecabling
Residential Cabling Guide
-------------------------------------

##-----------------------------------------------##
Article posted with Cabling-Design.com Newsgroup Archive
http://www.cabling-design.com/forums
no-spam read and post WWW interface to your favorite newsgroup -
sci.electronics.basics,sci.electronics.design,sci.electronics.misc - messages and counting!
##-----------------------------------------------##

CFoley1064 · Nov 30, 2004

Subject: Zener Diode ID
From: "Ronak Shah" ronaksh@nortelnetworks.com
Date: 11/30/2004 8:57 AM Central Standard Time
Message-id: <coi1p0$nl2$1@zcars0v6.ca.nortel.com

This might be the weirdes questen here....
Well I picked up a miex lot of components and it has about 5-6 Zener
Diodes... (thats what i think they are) Well the problem is they are sooo
tiny and hence I cant read the values.. is there a way I can find out the
values? I mean ID the diode....
Now that I think of it... are they even Zener diodes? I know 1N914 comes in
glass case too...
Is there a way I can find out what this is and what values it holds....

Hi, Shah. No weird questions here. If they're in a glass case, they're
probably either signal diodes or zeners. If they're zeners you can usually
tell the wattage by the size (400mW zeners are smaller than 1W zeners). The
tiny ones are usually the 400mW ones.

One thing you might try is cobbling up a 30V power supply, and putting the
back-biased diodes (Device Under Test, or DUT) in series with an appropriate
resistor. If they're standard diodes, all the voltage will be across the
diode. If they're zeners, there will be a zener voltage across the diode, and
the rest will be impressed across the resistor. Note that this will not be a
good solution for higher voltage zeners (they will look like standard diodes)
or schottky diodes (which can break down at 20V, depending). But, if the
choice is between standard silicon signal diode or low voltage (less than 24V)
zeners, this will give you a pretty good start.

Remember to start with a higher resistance value to avoid smoking the zener,
and after getting an initial indication of zener/avalanche, choose a more
reasonable resistance to test at something like half rated wattage. (power =
volts * current).

___
.--|___|---X----.
| R |
| |
| |
--- DUT -
-30VDC ^
| |
| |
'----------X----'
created by Andy´s ASCII-Circuit v1.24.140803 Beta www.tech-chat.de

Good luck
Chris

Randy Jacob · Dec 1, 2004

<HTML>
<HEAD>
<META NAME="GENERATOR" Content="Microsoft DHTML Editing Control">
<TITLE></TITLE>
</HEAD>
<BODY>
Hi Tom!&nbsp; 
&nbsp;<?xml:namespace prefix = o
ns = "urn:schemas-microsoft-com

ffice

ffice" /><o

></o

>
I hope this makes it to you.&nbsp; I will send a few times to be sure you
get it!
&nbsp;<o

></o

>
The URL for the book you are
looking for is below.&nbsp; Yes, its a
good resource, and its cheap!&nbsp; We
use it for our Entrepreneur clientele projects, and it has saved us a lot of
time, and Im sure money too!
&nbsp;<o

></o

>
Best regards,
Randy
&nbsp;<o

></o

>
<A
href="http://www.wiremarkltd.com/gybol/book.html">http://www.wiremarkltd.com/gybol/book.html</A>
&nbsp;<o

></o

>
&nbsp;<o

></o

>
<DIV
style="BORDER-RIGHT: medium none; PADDING-RIGHT: 0in; BORDER-TOP: medium none; PADDING-LEFT: 4pt; PADDING-BOTTOM: 0in; BORDER-LEFT: black 1.5pt solid; PADDING-TOP: 0in; BORDER-BOTTOM: medium none">
<P class=MsoNormal
style="BORDER-RIGHT: medium none; PADDING-RIGHT: 0in; BORDER-TOP: medium none; PADDING-LEFT: 0in; PADDING-BOTTOM: 0in; MARGIN: 0in 0in 0pt; BORDER-LEFT: medium none; PADDING-TOP: 0in; BORDER-BOTTOM: medium none; mso-margin-top-alt: auto; mso-margin-bottom-alt: auto; mso-border-left-alt: solid black 1.5pt; mso-padding-alt: 0in 0in 0in 4.0pt">&nbsp;<o

></o

></DIV>
<DIV
style="BORDER-RIGHT: medium none; PADDING-RIGHT: 0in; BORDER-TOP: medium none; PADDING-LEFT: 4pt; PADDING-BOTTOM: 0in; BORDER-LEFT: black 1.5pt solid; PADDING-TOP: 0in; BORDER-BOTTOM: medium none">
<P class=MsoNormal
style="BORDER-RIGHT: medium none; PADDING-RIGHT: 0in; BORDER-TOP: medium none; PADDING-LEFT: 0in; PADDING-BOTTOM: 0in; MARGIN: 0in 0in 0pt 3.75pt; BORDER-LEFT: medium none; PADDING-TOP: 0in; BORDER-BOTTOM: medium none; mso-margin-top-alt: auto; mso-margin-bottom-alt: auto; mso-border-left-alt: solid black 1.5pt; mso-padding-alt: 0in 0in 0in 4.0pt">----- Original Message -----
<o

></o

>
<P class=MsoNormal
style="BORDER-RIGHT: medium none; PADDING-RIGHT: 0in; BORDER-TOP: medium none; PADDING-LEFT: 0in; BACKGROUND: #e4e4e4; PADDING-BOTTOM: 0in; MARGIN: 0in 0in 0pt 3.75pt; BORDER-LEFT: medium none; PADDING-TOP: 0in; BORDER-BOTTOM: medium none; mso-margin-top-alt: auto; mso-margin-bottom-alt: auto; mso-border-left-alt: solid black 1.5pt; mso-padding-alt: 0in 0in 0in 4.0pt">From: Tom Jeffers <o

></o

>
<P class=MsoNormal
style="BORDER-RIGHT: medium none; PADDING-RIGHT: 0in; BORDER-TOP: medium none; PADDING-LEFT: 0in; PADDING-BOTTOM: 0in; MARGIN: 0in 0in 0pt 3.75pt; BORDER-LEFT: medium none; PADDING-TOP: 0in; BORDER-BOTTOM: medium none; mso-margin-top-alt: auto; mso-margin-bottom-alt: auto; mso-border-left-alt: solid black 1.5pt; mso-padding-alt: 0in 0in 0in 4.0pt">November 29, 2004 3:37
PM<o

></o

>
<P class=MsoNormal
style="BORDER-RIGHT: medium none; PADDING-RIGHT: 0in; BORDER-TOP: medium none; PADDING-LEFT: 0in; PADDING-BOTTOM: 0in; MARGIN: 0in 0in 0pt 3.75pt; BORDER-LEFT: medium none; PADDING-TOP: 0in; BORDER-BOTTOM: medium none; mso-margin-top-alt: auto; mso-margin-bottom-alt: auto; mso-border-left-alt: solid black 1.5pt; mso-padding-alt: 0in 0in 0in 4.0pt">Subject: Help Finding a Good eCommerce and
Project Book<o

></o

></DIV>
&nbsp;<o

></o

>
Hello,
&nbsp;<o

></o

>
Can anyone tell me where I can
find the eBook Getting Your Business Online?&nbsp; If I remember correctly it was compiled
by individuals working for a consulting company, but I do not recall which
one.&nbsp; We used the book for a lot of
our web development and software projects at my other job, and I think a few of
the construction or building companies we worked with used the project
management section for their projects.&nbsp;
The book was an invaluable project tool, was very easy to read and
understand, and covered just about everything you could imagine!&nbsp; Im sure someone out there has seen or
heard of it.&nbsp; I would like to review
this book before I plan to go online with a business I am starting.&nbsp; 
&nbsp;<o

></o

>
Any help would be greatly
appreciated!
&nbsp;<o

></o

>
Thanks!
Tom
&nbsp;
</BODY>
</HTML>

Clarence · Dec 3, 2004

"Jim Thompson" <thegreatone@example.com> wrote in message
news

q31r0dmc9ml2j0db8071i99k2m3vf2rrb@4ax.com...

On 3 Dec 2004 07:16:38 -0800, Winfield Hill
hill_a@t_rowland-dotties-harvard-dot.s-edu> wrote:

John Popelish wrote...

ravi kumar wrote:

when i am going through my book i read about active load & current
mirror .Current mirror can be used as an active load . please explain
me about these things with examples . Why should we consider these
things at the time of circuit design ?

http://www.allaboutcircuits.com/vol_6/chpt_5/14.html

Gag me with a spoon.

Now be nice. One day all of your engineering work will be out-sourced
to such folk ;-)

Hey, according to some sources THEY are the best and brightest workers for a

$.45 an hour rate!

Don Lancaster · Dec 4, 2004

Pig Bladder wrote:

On Thu, 18 Nov 2004 23:23:59 +0000, Robert Monsen wrote:

Dirk Bruere at Neopax wrote:
Don Kelly wrote:

"Dirk Bruere at Neopax" <dirk@neopax.com> wrote in message
news:303qj0F2qmmblU1@uni-berlin.de...

jsmith wrote:

THE ESSENCE OF OHMS LAW

by Jud Williams, Performance Power Technologies

I prefer the hose pipe analogy.

The pressure of water ie how far it squirts, is voltage.
The amount of water per second is currrent.
The size of the hose is resistance.
Power is the rate at which water is coming out.

-----------
The amount of water per second is the rate at which water is coming
out. Are
you saying that power and current are the same? Sorry- tain't so.

I know.
However, I didn't correct it after posting because I was trying to think
of a decent power analogy.

Voltage is really like the difference in level between two bodies of
liquid, which is called 'head'. (I'm not sure if it's equivalent to
pressure.)

It depends on your partner's attitude.

Then, energy is head * mass, and power is head * flow rate. Note that
energy and power has to be measured wrt the difference in levels, which
makes perfect sense. There is more potential energy with a fall of 100'
than a fall of 10'.

Now, use this fluid analogy to explain inductance...

--
The Pig Bladder From Uranus, still waiting for
some hot babe to ask what my favorite planet is.

See http://www.tinaja.com/glib/energfun.pdf for an energy fundamentals
tutorial.

--
Many thanks,

Don Lancaster
Synergetics 3860 West First Street Box 809 Thatcher, AZ 85552
voice: (928)428-4073 email: don@tinaja.com

Please visit my GURU's LAIR web site at http://www.tinaja.com

Rick Merrill · Dec 4, 2004

Denis Gleeson wrote:

Hello all

Without going into the application in too much detail we are looking
into
the possibility of allowing the identification of items through a
persons sense of touch.

So what I am researching at the moment is passing a waveform down a
pair of wires which when held (the wires that is) will allow the
person to identify that they have the correct item (correct pair of
wires in this case).

Is there any information out there on this sort of thing? Has anybody
tried this before? What sort of safety regulations etc. apply?

Limit to 5ma (c.f. GFI)

Maybe you wanto have a finger worn device that delivers the
"tingle code" based on RFID? That could enable a blind
clerk to work at a store someday.

I suggest you look into PWM (pulse width modulation).

Prior electrocutaneous example: http://kaz.med.wisc.edu/research.htm

Mac · Dec 4, 2004

On Sat, 04 Dec 2004 08:55:33 -0800, Denis Gleeson wrote:

Hello all

Without going into the application in too much detail we are looking
into
the possibility of allowing the identification of items through a
persons sense of touch.

So what I am researching at the moment is passing a waveform down a
pair of wires which when held (the wires that is) will allow the
person to identify that they have the correct item (correct pair of
wires in this case).

Is there any information out there on this sort of thing? Has anybody
tried this before? What sort of safety regulations etc. apply?

Any help or suggestions appreciated.

Regards

Denis

I don't know what regulations apply but it seems like this would be
exceptionally dangerous for people with electronic life-suppor
equipment implanted in their bodies. (I'm thinking of pacemakers here.)

Just something to keep in mind. Sorry I don't have any real information.

--Mac

Bob Masta · Dec 4, 2004

On 4 Dec 2004 08:55:33 -0800, dgleeson-2@utvinternet.com (Denis
Gleeson) wrote:

Hello all

Without going into the application in too much detail we are looking
into
the possibility of allowing the identification of items through a
persons sense of touch.

So what I am researching at the moment is passing a waveform down a
pair of wires which when held (the wires that is) will allow the
person to identify that they have the correct item (correct pair of
wires in this case).

Is there any information out there on this sort of thing? Has anybody
tried this before? What sort of safety regulations etc. apply?

To expand on what others have said, the main safety issue is
going to be keeping the current from passing through the
heart (for pacemakers of just those with sensitive hearts),
which basically means somehow guaranteeing that the
current path is all in one hand, never from one hand to
the other, or to an external ground, etc.

One practical problem you will quickly encounter is that
the voltage needed to produce a given current varies
quite widely, since the skin pads of the finger tips are
not very conductive when dry.

Best regards,

Bob Masta
dqatechATdaqartaDOTcom

D A Q A R T A
Data AcQuisition And Real-Time Analysis
www.daqarta.com

Rich Grise · Dec 4, 2004

On Sat, 04 Dec 2004 08:55:33 -0800, Denis Gleeson wrote:

Hello all

Without going into the application in too much detail we are looking
into
the possibility of allowing the identification of items through a
persons sense of touch.

So what I am researching at the moment is passing a waveform down a
pair of wires which when held (the wires that is) will allow the
person to identify that they have the correct item (correct pair of
wires in this case).

Is there any information out there on this sort of thing? Has anybody
tried this before? What sort of safety regulations etc. apply?

Any help or suggestions appreciated.

I've seen articles on a device with a little X-Y matrix of tiny little

transducers, which when they're energized, the person can feel the
vibrating ones somewhat like Braille. The app has a little sensor array,
and they were using it to read ordinary text by feel.

Or, just Braille tags.

But don't ever do anything that intentionally gives people an electrical
shock, except under strictly controlled lab or medical conditions.

Or gags, like those lighters and books, but even they're illegal to sell
these days.

Good Luck!
Rich

steve · Dec 4, 2004

dgleeson-2@utvinternet.com (Denis Gleeson) wrote in message news:<184c35f9.0412040855.6a4a25df@posting.google.com>...

Hello all

Without going into the application in too much detail we are looking
into
the possibility of allowing the identification of items through a
persons sense of touch.

So what I am researching at the moment is passing a waveform down a
pair of wires which when held (the wires that is) will allow the
person to identify that they have the correct item (correct pair of
wires in this case).

Is there any information out there on this sort of thing? Has anybody
tried this before? What sort of safety regulations etc. apply?

Any help or suggestions appreciated.

Regards

Denis

An easier solution would be to use vibration, a small vibration motor
(the type used in pagers), for instance, attached to the item can give
the same tactile feeling (tingling) without the danger or headaches of
passing currents thru items (and people!). Whether its practical or
not depends on your specific application.

Jim Douglas · Dec 5, 2004

Check out the medical device called a "Tens" unit, it's send a small tingle.

"Denis Gleeson" <dgleeson-2@utvinternet.com> wrote in message
news:184c35f9.0412040855.6a4a25df@posting.google.com...

Hello all

Without going into the application in too much detail we are looking
into
the possibility of allowing the identification of items through a
persons sense of touch.

So what I am researching at the moment is passing a waveform down a
pair of wires which when held (the wires that is) will allow the
person to identify that they have the correct item (correct pair of
wires in this case).

Is there any information out there on this sort of thing? Has anybody
tried this before? What sort of safety regulations etc. apply?

Any help or suggestions appreciated.

Regards

Denis

Chip with simple program for Toy

Rich The Philosophizer

Guest

Clarence

Guest

Robert Monsen

Guest

The Phantom

Guest

John Fields

Guest

The Phantom

Guest

Don Kelly

Guest

rayjking

Guest

Tom MacIntyre

Guest

Dmitri(Cabling-Design.com

Guest

CFoley1064

Guest

Randy Jacob

Guest

Clarence

Guest

Don Lancaster

Guest

Rick Merrill

Guest

Mac

Guest

Bob Masta

Guest

Rich Grise

Guest

steve

Guest

Jim Douglas

Guest

Log in

Welcome to EDABoard.com

Sponsor