Driver to drive?

[Stefan Heinzmann]

Boris Mohar wrote:

On 20 Dec 2004 08:04:26 -0800, shoppa@trailing-edge.com wrote:

I had some fun this past weekend building an analog computer to
integrate the Lorenz equations. I started with Paul Horowitz's
design at

http://frank.harvard.edu/~paulh/misc/lorenz.htm

Here's another implementation:
http://www.electronicsletters.com/papers/0012/paper.html

--
Cheers
Stefan

 

[Jim Thompson]

On Mon, 20 Dec 2004 23:02:03 GMT, "Martin Riddle"
<martinriddle@hotmail.com> wrote:

Isnt MEMPHIS, TN their main Hub? Every thing goes thru there regardless of the destination. Weird, but supposed to be highly
efficient.

[snip]

Most of the time, but I had a recent package that went...

Shanghai
Subic Bay, Philippines
Anchorage
Phoenix

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice480)460-2350 | |
| E-mail Address at Website Fax480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |

I love to cook with wine. Sometimes I even put it in the food.

 

[Rich Webb]

On 18 Dec 2004 02:54:13 -0600, me <me@here.net> wrote:

Cheers!
Rich


dumb ass...


-----------== Posted via Newsfeed.Com - Uncensored Usenet News ==----------
http://www.newsfeed.com The #1 Newsgroup Service in the World!
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Got to have respect for manly men who dispense insults anonymously.

--
Rich Webb Norfolk, VA

 

[Mac]

On Mon, 20 Dec 2004 16:22:34 -0500, Active8 wrote:

As for a resistor, as I said, there's no fine control. a 9 mA change
through 5k is 45 V whereas that same change through the Vbe mult

Of course you mean 4.5 Volts.

--Mac

 

[Don Klipstein]

In article <LRIxd.2741$fe5.962@trndny06>, Martin Riddle wrote:

Isnt MEMPHIS, TN their main Hub? Every thing goes thru there regardless
of the destination. Weird, but supposed to be highly efficient.

Memphis is their main hub. If the tracking info shows Memphis, that is
the likely explanation.

But do not expect every package to go through Memphis - I have a client
in Toronto and I ship from the metropolitan area of Philadelphia, and many
but not all packages that I ship to Toronto go through Memphis. Many go
on a more directly northward path without any hopping to Memphis.

But I do expect most Fedex express packages go to Memphis to change
planes in a hub-spoking sort of way.

- Don Klipstein (don@misty.com)

 

[Don Klipstein]

In article <qsmes05771ten2hd7t8i51icp0edj7e844@4ax.com>, Jim Thompson wrote:

On Mon, 20 Dec 2004 23:02:03 GMT, "Martin Riddle"
martinriddle@hotmail.com> wrote:

Isnt MEMPHIS, TN their main Hub? Every thing goes thru there
regardless of the destination. Weird, but supposed to be highly
efficient.

Most of the time, but I had a recent package that went...

Shanghai
Subic Bay, Philippines
Anchorage
Phoenix

Some fair amount of air travel across the Pacific makes a stop in
Alaska.

Try stretching a string over a globe from Tokyo, Shanghai, Beijing,
Soeul or other major cities of Japan, China or Korea to anywhere in the
"contiguous 48" states of the USA. Chances are Anchorage Alaska is not
really far out of the way. I believe the major package shipment companies
should have a secondary hub there if they don't already.

- Don Klipstein (don@misty.com)

 

[Richard Henry]

"Martin Riddle" <martinriddle@hotmail.com> wrote in message
news:LRIxd.2741$fe5.962@trndny06...

Isnt MEMPHIS, TN their main Hub? Every thing goes thru there regardless
of the destination. Weird, but supposed to be highly
efficient.

I heard many years ago stories of people fed-exing packages to other floors
in their building because of the reliable service and because they were
fed-exing a lot of packages anyway, and all of those packages went through
Memphis. Since then, I believe they have short-circuited the process in a
few appropriate ways - packages bound for the city of origin are intercepted
before loading on the flight, and some short trips (I am aware of Los
Angeles to San Diego, for instance) go by truck.

 

[ChrisGibboGibson]

This one I loved on an analogue computer.

Try 2(x^2)-1 with the output fed back to it's own input. Set initial 0<x<1

Chaos?

Gibbo

 

[Ban]

Active8 wrote:

On Mon, 20 Dec 2004 12:32:30 -0800, John Larkin wrote:

Why a Vbe multiplier? Mosfets don't need the temp tracking like
bipolars do.

I wasn't talking about Vbe mult biasing of a bjt CE amp. The Vbe
mult in the circuit has nothing to do with temp tracking.

It will change its value with temperature like a multiplied diode junction,
so when it was 4.5V at 25°C it will be only 3.96V at 65°C. A constant
current source with a resistor alone is independent of temperature.

I've mused on this, too. How about a simple bypassed resistor, pumped
by a current source?

Why the bypass? Maybe I'm not following you.

As for a resistor, as I said, there's no fine control. a 9 mA change
through 5k is 45 V whereas that same change through the Vbe mult
only results in mV changes.

Some side circuit would know when the signal
level was small or zero, measure fet current, and tweak the bias. A
small uP and a dac, maybe. The hard part is measuring the smallish
fet idle currents...

Is 100 mA typical?

maybe a sense resistor in one of the power rails,

Not, both? But why in the drain?

50-70mA is typical, to have some accuracy we would need at least 0.1V
voltage drop, which corresponds to 2 ohm. Now if the max. current is 15A,
there would be 30V loss, that is why the resistor has to be bypassed with a
hefty schottky diode. You would then sample the voltage whenever the output
goes through zero. You need only one resistor, because when the output is
zero, the current in the other arm must be of equal value. If you put the
sense resistor in the source line the varying voltage drop affects the bias
setting.

shunted by a hefty diode. I like having no source resistors, except
for the current-limit thing.

How do you limit current without a much greater R than the typical
0.1R source R?

Or just use a pot!

And a robotic arm to turn it?

you didn't get it, sorry
--
ciao Ban
Bordighera, Italy

 

[Frithiof Andreas Jensen]

"John Fields" <jfields@austininstruments.com> wrote in message
news:nidbs0pkb2beu5gavm14th329poufgsorq@4ax.com...

You can do it with an oscilloscope and a resistive shunt to measure
the current. Display voltage on one channel, current on the other,
determine the phase angle between them and then P = IE cos(phi).

Sure - You can also pop down the shop and buy a Power Meter which plugs into
the socket and the appliance on the other side - like one of those timer
watches. If you program the kWh price into it, it will calculate the Daily,
Weekly & Annual costs of running the appliance when left there long enough
to get capture the use pattern.

They cost about USD 20 - much less than an hour of my time!

 

[Active8]

On Tue, 21 Dec 2004 05:08:02 GMT, Mac <foo@bar.net> wrote:

On Mon, 20 Dec 2004 16:22:34 -0500, Active8 wrote:

As for a resistor, as I said, there's no fine control. a 9 mA change
through 5k is 45 V whereas that same change through the Vbe mult

Of course you mean 4.5 Volts.

5000 * .009 = 45

Best Regards,
Mike

 

[Lou Pecora]

In article <5yGxd.5232$Z47.4945@newsread2.news.atl.earthlink.net>,
"Nicholas O. Lindan" <see@sig.com> wrote:

The temperature, Down Jones average, height of blades of grass ...

The temperature? Maybe since it's connected to the weather system which
can display chaotic behaviors, but it's VERY high dimensional. That
would be a BIG circuit.

Dow Jones? Nah. Best modeled as a stochastic system. If you think the
weather is high dimensional...

Blades of Grass? Huh? I don't get that one. Fractal, maybe? Maybe,
not. Connection to chaos or dynamics?

Being Cyclic is not a necessary trait of chaos.

Look (google) for simpler systems. Check out papers by Tom Carroll (in
the 1990's), Sprott (1990's and later), Rulkov (late 1990's paper on
just your topic), and the double-scroll circuit (often mislabeled as
Chua's circuit, but that latter label has stuck).

-- Lou Pecora (my views are my own)

 

[Nicholas O. Lindan]

"K1G1" <none225@someone.com> wrote in message
news:LYQxd.232337$V41.43516@attbi_s52...

While reading this article
http://instruct1.cit.cornell.edu/courses/ee476/ideas/singlesupply.pdf
It talks about star grounds and has certain components grounded by star
grounds. What are they?

The wires/traces all come together at one point (hence the moniker)
and one conductor goes from this point to wherever the next level
ground is.

--
Nicholas O. Lindan, Cleveland, Ohio
Consulting Engineer: Electronics; Informatics; Photonics.
Remove spaces etc. to reply: n o lindan at net com dot com
psst.. want to buy an f-stop timer? nolindan.com/da/fstop/

 

[Steve O'Hara-Smith]

On Tue, 21 Dec 2004 15:09:36 GMT
"Nicholas O. Lindan" <see@sig.com> wrote:

I think it is: if the values aren't cyclic then they have to
march of to infinity (or the universe ends).

Hmm think about the digits in pi.

 

[Ralph Barone]

In article <10sf84qd4rg0g6d@corp.supernews.com>,
Steve Dunbar <stvdnb@yahoo.com> wrote:

http://www.sandman.com/rubberb.html

That looks like a great product. However, on the same site sits
http://www.sandman.com/telco.html

I personally liked the phone line powered car battery charger. That's
gotta take a long time to work.

 

[Lou Pecora]

In article <L7Yxd.5967$Z47.1623@newsread2.news.atl.earthlink.net>,
"Nicholas O. Lindan" <see@sig.com> wrote:

Eventually this devolves to agreement/disagreement on the meaning of
the word 'chaos'. Best not get too close to the nut of the matter or
it will disappear in a puff of smoke (flame?).

The definition of chaos is very rigorous and precise. It's the
definition of 'random' that is the problem.

-- Lou Pecora (my views are my own)

 

[Active8]

On Tue, 21 Dec 2004 08:05:53 GMT, Ban wrote:

50-70mA is typical,

Thank you.

to have some accuracy we would need at least 0.1V
voltage drop, which corresponds to 2 ohm.

LTI1166 data sheet disagrees - works for their app.

Now if the max. current is 15A,
there would be 30V loss, that is why the resistor has to be bypassed with a
hefty schottky diode. You would then sample the voltage whenever the output
goes through zero. You need only one resistor, because when the output is
zero, the current in the other arm must be of equal value. If you put the
sense resistor in the source line the varying voltage drop affects the bias
setting.

Yeah. You'd need resistors on at least half of the sources then.
Thanks.

Or just use a pot!

And a robotic arm to turn it?

you didn't get it, sorry

A joke?
--
Best Regards,
Mike

 

[Highland Ham]

If it were mine, I would first try a spritz of contact cleaner into
the switch via the front panel slot (IIR465C). All contact
cleaners are the same - mineral oil and alcohol - so the cheapest
Radio Shack stuff works as well as anything. WD40 also works well.
==============================

On various occsasions I have been told that WD40 is NOT the right cleaning
agent for electrical systems involving plastic insulation re wiring, etc. I
always use (non chlorinated) contact cleaner as available from Rat Shack and
similar stores.
Here in the UK I use contact cleaner supplied by Maplin.

Frank GM0CSZ / KN6WH

 

[Ian Stirling]

Frithiof Andreas Jensen <frithiof.jensen@die_spammer_die.ericsson.com> wrote:

"John Fields" <jfields@austininstruments.com> wrote in message
news:nidbs0pkb2beu5gavm14th329poufgsorq@4ax.com...
You can do it with an oscilloscope and a resistive shunt to measure
the current. Display voltage on one channel, current on the other,
determine the phase angle between them and then P = IE cos(phi).

Sure - You can also pop down the shop and buy a Power Meter which plugs into
the socket and the appliance on the other side - like one of those timer
watches. If you program the kWh price into it, it will calculate the Daily,
Weekly & Annual costs of running the appliance when left there long enough
to get capture the use pattern.

They cost about USD 20 - much less than an hour of my time!

And have the added fun of being several hundred percent out on some
loads.

 

[John Woodgate]

I read in sci.electronics.design that metasynths@netscape.net wrote (in
<1103660674.960908.86920@f14g2000cwb.googlegroups.com&gt about 'Neato
chaotic equations for analog computers to display?', on Tue, 21 Dec
2004:

has anyone created a nonlinear/chaotic circuit in SPICE?

Intentionally? (;-)
--
Regards, John Woodgate, OOO - Own Opinions Only.
The good news is that nothing is compulsory.
The bad news is that everything is prohibited.
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk