Driver to drive?

[krw]

In article <j9htm45ds173qs50lmkm6gdsgrtvt19nq5@4ax.com>,
quiettechblue@yahoo.com says...>

On Wed, 14 Jan 2009 22:36:47 +0100, "Frithiof Jensen"
frithiof.jensen@diespammerdie.jensen.tdcadsl.dk> wrote:


"Too_Many_Tools" <too_many_tools@yahoo.com> skrev i meddelelsen
news:012bdd20-fa16-4f5d-88db-6241d9d3eb14@z6g2000pre.googlegroups.com...
On Jan 10, 6:01 pm, Gunner Asch <gun...@NOSPAMlightspeed.net> wrote:

Correct..and state and local tax revenues continue to tank in CA.

So how are we going to make up the difference Gunner?

Start printing IOU's to state emplyees instead of real money?

TMT

And for state income tax refunds.

They'll have to pay interest, which they won't have next year.
There is a reason I always owe money at the end of the year. It's
easier to pay the IRS than to beat it out of them.

 

[krw]

In article <gkmo4a$tp3$1@reversiblemaps.ath.cx>, jasen@xnet.co.nz
says...>

On 2009-01-14, JosephKK <quiettechblue@yahoo.com> wrote:
On Mon, 12 Jan 2009 18:24:12 GMT, Richard The Dreaded Libertarian
null@example.net> wrote:


That is already taxed at the state level (in most states) Do you want
to add a Federal tax to that (even at the hope of eliminating personal
income tax, it would be very high ~ 20%). Do you think the sheeple
would allow that? Don't pester us again without numbers that show tax
dollars versus income for your scheme.

I think he means a tax on turnover instead of on profit

such a tax could lead to upheaval in many low-margin sectors
and will be unpopular with MLM organisations like Amway.

Vermont tried to institute a "gross receipts" tax a few years back,
but the leftist loons lost that battle at the last minute. I
expect them to win it eventually though. By their nature they
don't understand economics past their last welfare check.

 

[krw]

In article <81ltm41oj81nlvlrllv6eiih3gi6d13v8s@4ax.com>,
jjlarkin@highNOTlandTHIStechnologyPART.com says...>

On Sat, 10 Jan 2009 03:22:32 +0000, Eeyore
rabbitsfriendsandrelations@hotmail.com> wrote:



Joerg wrote:

Big American cars are usually pretty good, comfortable and (when driven
gently) quite economical. Got 20mpg on a fully equipped Suburban and
also on a fully loaded Crown Victoria.

20 mpg is economical ?


At $1.70 a gallon, sure.

It's been $1.35 here for a month or so, though just went up to
$1.65, I guess because oil wend down to $38/bbl. :-/

....even cheaper as Bush leaves office than when he came into
office. ;-)

 

[krw]

In article <59mtm49mpofommcena8kct20ksg82hc2io@4ax.com>,
quiettechblue@yahoo.com says...>

On Sun, 11 Jan 2009 12:39:46 -0600, krw <krw@att.bizzzzzzzzzzz> wrote:

On Sun, 11 Jan 2009 18:20:44 +0000, Eeyore
rabbitsfriendsandrelations@hotmail.com> wrote:



krw wrote:

Eeyore <rabbitsfriendsandrelations@hotmail.com> wrote:
T wrote:
jjlarkin@highNOTlandTHIStechnologyPART.com says...

I don't necessarily blame the paralysis on the unions. On the other hand
the perfect example is GM.

Several new Saturns are actually German Opels. Seems GM can't even design a car
any more.

...and Opel is owned by?

I know perfectly well who by. The Germans put the Americans to shame. Or can you
think of another reason why GM would be importing German cars and designs ?

The same reason other multi-national corporations "import designs"
from other subsidiaries, Dumb Donkey.

Opel won't go under. Neither will Saab, I expect. They actually have the technology.

What a dumb donkey. They are OWNED BY GM and will go where GM goes,
Dumbass Fugly Donkey.

And GM seems headed for bankruptcy, even with the bail out. Next.

Agreed, however

1) Saab will follow them, as a wholly owned subsidiary

2) "Bankruptcy" does not mean "end of operations".

 

[JosephKK]

On Sat, 10 Jan 2009 00:18:05 +0000, Chris Jones <lugnut808@yahoo.com>
wrote:

acannell@gmail.com wrote:

Im sure this has been done before, right?

Two NTC thermistors.

10k @ 25C
Beta = 3380

I'd like a circuit which outputs a voltage which is the difference in
temperature between the two resistors.

But it needs to be linear.

I.e.

1 degree difference = 0.1V
10 degree difference = 1V
100 degree difference = 10V

At ANY location in the thermistors operating range.

Im trying to get my head around this....what is the mathematical
function for what Im trying to do? Since the thermistor is non-linear?

Im thinking a circuit which linearizes each thermistors resistance vs.
temperature, and then another which simply does a voltage difference.

Sound right?

I can do the voltage difference, but how do I do the linearizer?

You can do a reasonable approximation over a small range of temperatures
using analogue circuitry but for a general solution that works for all
temperatures, I believe that you should use a microcontroller to do the
maths. You could digitise the thermistor resistances either by connecting
them in some kind of resistive divider with an ADC, or connect them into
R-C oscillators e.g. with 555 timer chips, or you could measure the time
constant of a R-C network made with the thermistors as the resistors, using
a microcontroller port pin and a comparator.

Chris

Bah. Just use a logarithmic amplifier / converter. Build it if you
have to, they are fairly simple (Never more than 4 bjt, some r's and
an opamp).

Also a well designed bridge can linearize it over a moderate
temperature range.

 

[MooseFET]

On Jan 14, 7:25 pm, Sylvia Else <syl...@not.at.this.address> wrote:

Phil Allison wrote:
"Moronic Cunt FET"

Etc.

I notice you've gone back to changing subject lines, Phil. Didn't take
long, did it?

Unfortunately he appears to be unable to moderate his behavior. He
latches up into the raving anger mode so often that his posts don't
average out to worth reading. He won't now go back and read your
earlier posts and realize that he is wrong, so we can expect the storm
to continue for a while.

 

[MooseFET]

On Jan 14, 11:20 pm, Jasen Betts <ja...@xnet.co.nz> wrote:

On 2009-01-14, JosephKK <quiettechb...@yahoo.com> wrote:

On Mon, 12 Jan 2009 18:24:12 GMT, Richard The Dreaded Libertarian
n...@example.net> wrote:
That is already taxed at the state level (in most states) Do you want
to add a Federal tax to that (even at the hope of eliminating personal
income tax, it would be very high ~ 20%).  Do you think the sheeple
would allow that?  Don't pester us again without numbers that show tax
dollars versus income for your scheme.

I think he means a tax on turnover instead of on profit

such a tax could lead to upheaval in many low-margin sectors
and will be unpopular with MLM organisations like Amway.

A VAT tax is better. If you tax the interactions between people and
organizations based on the value you place an even greater bias
towards the creation of a single large monopoly. When you tax only
the increase in value, there is less of a bias in that direction.

To prevent the bias from strongly favoring the multinational companies
over you local industries, the tax must also be applied to imports.
If you don't do that the multinationals will import the product from
their external arm and declare the value at the time of import to be
110% of the sales value. When they then sell it at 100% of its value,
they will have a -10% value added and thus the government will have to
cut them a check.

 

From: Tony Lance <judemarie@bigberthathing.co.uk>
Newsgroups: swnet.sci.astro,sci.space.policy
Subject: Re: Big Bertha Thing pin-wheel
Date: Wed, 11 Apr 2007 17:19:41 +0100

Big Bertha Thing uniform
Cosmic Ray Series
Possible Real World System Constructs.
http://www.tonylance.talktalk.net/uniform.html
Access page to 714K ZIP file
Astrophysics net ring Access site
Newsgroup Reviews including alt.support.attn-deficit

Animated wire-frame Polyhedron display,
complete with duals and double precision
angles to the polygons. Also technical
program description and 75 pictures.

Just one thing, thats still outstanding.
This is a collection of PostScript files from
the Computing Science Technical Report series
of organization 1127 of AT&T Bell Laboratories
report Comp. Sci. Tech. Rep. No. 130
author Andrew Hume
title Exact Descriptions of Regular
and Semi-Regular Polyhedra and Their Duals
date November 1986
tm TM 11276-861022-09
type techreport

Just two programs ready to run.
1. kaleido.exe (MSDOS) 86KB (see Zip)
2. schwarz.exe (MSDOS) 27KB (see Zip)

Just one description of two programs,
that do just one thing, better than the next best thing.
uniform.pdf (Adobe) 676KB (see Zip)


NB (2008)
A computer program, called kaleido (cf. [Ha]) and
publicly available at ftp@ftp.math.technion.ac.il,
has been developed to compute the data of a uniform
polyhedron (and its dual)...

Kaleido is also capable of computing the vertex and
face coordinates and displaying a rotating wire-frame
image of each polyhedron.

Two quotes from following attribution:-
Uniform Solution for Uniform Polyhedra*
Zvi Har’El
Department of Mathematics
Technion - Israel Institute of Technology
Haifa 32000, Israel
E-Mail: rl@math.technion.ac.il

* In memoriam of my father, Gershon Har’El, who introduced me to
spatial structures.
Geometriae Dedicata 47: 57-110, 1993.


From: Tony Lance <judemarie@bigberthathing.co.uk>
Newsgroups: swnet.sci.astro,sci.space.policy
Subject: Re: Big Bertha Thing Extract
Date: Sun, 22 Apr 2007 15:16:54 +0100

Big Bertha Thing francis

To my brother-in-law Francis (RIP),
who I once called "as daft as a brush."
To his everlasting credit,
he replied "I know."

The greatest compliment,
my wife ever paid me,
was to say, that I did not hold a grudge.
Net surfers do not hold grudges,
but they are a bit short on victim support,
whichever side the victim comes from.

+++++++++++++++++++++++++++++++++++
tonyla...@myinternetuk.com wrote:

From: Tony Lance <judemarie@bigberthathing.co.uk
Newsgroups: swnet.sci.astro,sci.space.policy
Subject: Big Bertha Thing redoubt
Date: Sun, 01 Apr 2007 18:28:32 +0100

Big Bertha Thing memoriam

 

On 15 jan, 09:19, James Arthur <bogusabd...@verizon.net> wrote:

bill.slo...@ieee.org wrote:
On 13 jan, 01:20, James Arthur <bogusabd...@verizon.net> wrote:
John Larkin wrote:
On Mon, 12 Jan 2009 11:37:25 -0800, Gunner Asch
gun...@NOSPAMlightspeed.net> wrote:
On Mon, 12 Jan 2009 04:10:01 -0800 (PST), bill.slo...@ieee.org wrote:
Keep in mind that most historians and economists believe that if Hoover
and FDR had left well enough alone, that the Great Depression would have
been over in less than 3 yrs, instead of dragging it out for 11
Most of the historians and economists incarcerated in a lunatic asylum
near you?
It's not an opinion that I'v ever heard, but I don't read histories
that have been crafted to appeal to right-wing Republicans.
Perhaps you could name a few authors and some of the books that tout
this interesting theory?
Lowell Vedder and Richard Gallaway,  Out of Work: Unemployment and
Government in Twentieth Century America
Wartime Prosperity? A Reassessment of the U.S. Economy in the 1940s
Robert Higgs
Brad DeLong's "Slouching Towards Utopia?: The Economic History of the
Twentieth Century
You may wish to google "leave it alone Liquidationists"
Okay. The argument is that the unemployed should have been forced back
into work at starvation wages by reducing or eliminating unemployment
benefit - in as far as Roosevelt increased the the payments to the
unemployed, he was thus doing the wrong thing.
again you are in error....
http://www.universityofcalifornia.edu/news/article/6550
http://www.amazon.com/FDRs-Folly-Roosevelt-Prolonged-Depression/dp/07....
Shrug...why not admit you were parroting the popular (but incorrect)
party line?
Gunner
Giving money to the poor, to keep them from misery, is an admirable
act of charity. But since they will immediately spend it, the money
competes in the marketplace and drives up prices for everyone else.
This is pure income redistribution, which always has overheads. There
is no "pump priming" here... spending on consumption creates no
investment, no productivity, no goods, no jobs. The effects are
apparently short-term good, actually long-term bad.
A society can't, longterm, consume more than it produces. Well, unless
they steal it.
Sloman is on the receiving end of redistributionist economics, so of
course he approves the theory.
John
"The government that robs Peter to pay Paul can always
count on the support of Paul." --G.B. Shaw

Peter being the regular taxpayer, and Paul the "defence" industries?

We spend but a trifle on defense; two-thirds of our money goes
to the dole, and only about one-in-four contributes.

Numbers? The last time you posted a similar claim, it turned out that
your idea of "the dole" included a surprising number of catagories
that didn't have any obvious association with unemployment benefits.

http://www.gpoaccess.gov/usbudget/fy09/pdf/budget/tables.pdf

at table S-8 suggests that defence spending is slightly bigger than
social security, at about a quarter of the budget, which is scarcely a
"trifle".

--
Bill Sloman, Nijmegen

 

[Jan Panteltje]

I wrote:

No, I am not talking about a feed forward design.

I did mean this:
10mV reference
|
noisy DC source -- series regulator --- negative peak detector - level comparator ----
| |
| |
------------------------<----------------------------------


The negative peaks only, because the positive peaks will just be regulated out anyways.
Not sure it will work....

And here is the opamp version without the discrete log tail pair.
Did not have to change a thing
ftp://panteltje.com/pub/300_millivolt_ripple_opamp.gif

 

[James Arthur]

bill.sloman@ieee.org wrote:

On 15 jan, 09:19, James Arthur <bogusabd...@verizon.net> wrote:
bill.slo...@ieee.org wrote:
On 13 jan, 01:20, James Arthur <bogusabd...@verizon.net> wrote:
John Larkin wrote:
On Mon, 12 Jan 2009 11:37:25 -0800, Gunner Asch
gun...@NOSPAMlightspeed.net> wrote:
On Mon, 12 Jan 2009 04:10:01 -0800 (PST), bill.slo...@ieee.org wrote:
Keep in mind that most historians and economists believe that if Hoover
and FDR had left well enough alone, that the Great Depression would have
been over in less than 3 yrs, instead of dragging it out for 11
Most of the historians and economists incarcerated in a lunatic asylum
near you?
It's not an opinion that I'v ever heard, but I don't read histories
that have been crafted to appeal to right-wing Republicans.
Perhaps you could name a few authors and some of the books that tout
this interesting theory?
Lowell Vedder and Richard Gallaway, Out of Work: Unemployment and
Government in Twentieth Century America
Wartime Prosperity? A Reassessment of the U.S. Economy in the 1940s
Robert Higgs
Brad DeLong's "Slouching Towards Utopia?: The Economic History of the
Twentieth Century
You may wish to google "leave it alone Liquidationists"
Okay. The argument is that the unemployed should have been forced back
into work at starvation wages by reducing or eliminating unemployment
benefit - in as far as Roosevelt increased the the payments to the
unemployed, he was thus doing the wrong thing.
again you are in error....
http://www.universityofcalifornia.edu/news/article/6550
http://www.amazon.com/FDRs-Folly-Roosevelt-Prolonged-Depression/dp/07...
Shrug...why not admit you were parroting the popular (but incorrect)
party line?
Gunner
Giving money to the poor, to keep them from misery, is an admirable
act of charity. But since they will immediately spend it, the money
competes in the marketplace and drives up prices for everyone else.
This is pure income redistribution, which always has overheads. There
is no "pump priming" here... spending on consumption creates no
investment, no productivity, no goods, no jobs. The effects are
apparently short-term good, actually long-term bad.
A society can't, longterm, consume more than it produces. Well, unless
they steal it.
Sloman is on the receiving end of redistributionist economics, so of
course he approves the theory.
John

"The government that robs Peter to pay Paul can always
count on the support of Paul." --G.B. Shaw

Peter being the regular taxpayer, and Paul the "defence" industries?

We spend but a trifle on defense; two-thirds of our money goes
to the dole, and only about one-in-four contributes.

Numbers? The last time you posted a similar claim, it turned out that
your idea of "the dole" included a surprising number of catagories
that didn't have any obvious association with unemployment benefits.

http://www.gpoaccess.gov/usbudget/fy09/pdf/budget/tables.pdf

at table S-8 suggests that defence spending is slightly bigger than
social security, at about a quarter of the budget, which is scarcely a
"trifle".

--
Bill Sloman, Nijmegen

Last time I supported my claim, in detail, we just differed
on definitions: you'd call 'em entitlements. To me, getting
someone else's money is the dole.

http://perotcharts.com/category/federal-budget-charts/page/9/

Give social spending its share of the interest, plus its share
of the discretionary items, and yep, it's about two-thirds.

Naturally the war has bumped up defense spending for the moment--
that's a blip, an anomaly. We know you of all people understand
blips. Even so--even in war time--it's only 550/2,730 = 20%.

Hey, when I went to get easy, illustrative pie-charts, I
found this cartoon:

http://perotcharts.com/

Cheers,
James Arthur

 

[Richard The Dreaded Liber]

On Thu, 15 Jan 2009 08:19:42 +0000, James Arthur wrote:

Problem is, we've got too many Pauls, not enough Peters, and that's why
we're having trouble paying the Bills.

Too many socialists with the "authority" to rob Peter.

Thanks,
Rich

 

[Richard The Dreaded Liber]

On Thu, 15 Jan 2009 02:05:40 -0500, Ben Bradley wrote:

On Fri, 9 Jan 2009 09:48:54 +0100, Frank Buss <fb@frank-buss.de> wrote:
Eeyore wrote:

Dorothy Willows saw orangeyyellow spheres. 'I don't believe in UFOs but
it was a low-flying object,' said Mrs Willows.

I believe in UFOs. It means just Unidentified Flying Object.

That damn initialism has been redefined by the UFOlogists and other
flying-caucer chasers to mean sonething like a real live LGM-piloted
craft. Never mind the judgement-neutral straight interpretation of the
initialism - doing that is so old-fashioned, so, um, "rational."

It's this overloading of the language that causes much
miscommunication (between different human beings - never mind between
humans and aliens).

Or even "Land of the Free" - Free what? =:-O

Thanks,
Rich

 

[Rich Grise]

On Thu, 15 Jan 2009 11:25:04 +0100, Skybuck Flying wrote:

Bye,
Skybuck

Oh, if only!

 

[James Arthur]

JosephKK wrote:

On Tue, 13 Jan 2009 00:42:41 GMT, James Arthur
bogusabdsqy@verizon.net> wrote:

Bill Sloman wrote:
"John Larkin" <jjlarkin@highNOTlandTHIStechnologyPART.com> schreef in
This is pure income redistribution, which always has overheads. There
is no "pump priming" here... spending on consumption creates no
investment, no productivity, no goods, no jobs.
It may not create new investment, but it may prevent old investment
being lost when businesses are bankrupted and their assets - that used
to form coherent and productive systems - are sold off as junk.

Since the extra spending goes on stuff that has to be produced, it
does encourage production and preseve jobs.

Your logic sucks.
We've just heard the sing-song about how everything's been
broken, and we can't afford eight more years of it.

The solution, it seems, is to absolutely flood failure with
money, to make absolutely sure we get at least eight more
years of it.

Brilliant.

Cheers,
James Arthur

Have to be picky here, Bush the lesser started with giving the flood
of relief to "fool" banksters, Obama hasn't even had the chance yet.

No, that's right, not picky. No quarrel here. Facts are facts.
But his nemeses--who made the charge all was rotten--are the most
eager to preserve it.

Cheers,
James Arthur

 

[Chris Jones]

JosephKK wrote:

On Sat, 10 Jan 2009 00:18:05 +0000, Chris Jones <lugnut808@yahoo.com
wrote:

acannell@gmail.com wrote:

Im sure this has been done before, right?

Two NTC thermistors.

10k @ 25C
Beta = 3380

I'd like a circuit which outputs a voltage which is the difference in
temperature between the two resistors.

But it needs to be linear.

I.e.

1 degree difference = 0.1V
10 degree difference = 1V
100 degree difference = 10V

At ANY location in the thermistors operating range.

Im trying to get my head around this....what is the mathematical
function for what Im trying to do? Since the thermistor is non-linear?

Im thinking a circuit which linearizes each thermistors resistance vs.
temperature, and then another which simply does a voltage difference.

Sound right?

I can do the voltage difference, but how do I do the linearizer?

You can do a reasonable approximation over a small range of temperatures
using analogue circuitry but for a general solution that works for all
temperatures, I believe that you should use a microcontroller to do the
maths. You could digitise the thermistor resistances either by connecting
them in some kind of resistive divider with an ADC, or connect them into
R-C oscillators e.g. with 555 timer chips, or you could measure the time
constant of a R-C network made with the thermistors as the resistors,
using a microcontroller port pin and a comparator.

Chris

Bah. Just use a logarithmic amplifier / converter. Build it if you
have to, they are fairly simple (Never more than 4 bjt, some r's and
an opamp).

Also a well designed bridge can linearize it over a moderate
temperature range.

I have done this with analogue circuitry for bolometers, using a bridge
circuit with excitation that was adjusted so that the bolometer sensitivity
was less dependent on the ambient temperature. It was ok at room
temperature but the sensitivity was not as stable over wider ranges of
ambient temperature, nor as linear over bolometer input power as I could
have achieved with a good ADC and a microcontroller. If you don't require
very high accuracy over a wide range of ambient temperature, or you think
that circuits containing several analogue multipliers and more than three
interacting trimpots are a good idea then you might want to avoid the $5
microcontroller.

Chris

 

[Phil Allison]

"MooseFET"

He won't now go back and read your
earlier posts and realize that he is wrong,


** You LYING piece of autistic SHIT !!!!

YOU misread what had been posted and YOU will not go back and look at it
again.




...... Phil

 

On 15 jan, 20:25, James Arthur <bogusabd...@verizon.net> wrote:

bill.slo...@ieee.org wrote:
On 15 jan, 09:19, James Arthur <bogusabd...@verizon.net> wrote:
bill.slo...@ieee.org wrote:
On 13 jan, 01:20, James Arthur <bogusabd...@verizon.net> wrote:
John Larkin wrote:
On Mon, 12 Jan 2009 11:37:25 -0800, Gunner Asch
gun...@NOSPAMlightspeed.net> wrote:
On Mon, 12 Jan 2009 04:10:01 -0800 (PST), bill.slo...@ieee.org wrote:

<snip>

"The government that robs Peter to pay Paul can always
count on the support of Paul." --G.B. Shaw

Peter being the regular taxpayer, and Paul the "defence" industries?

We spend but a trifle on defense; two-thirds of our money goes
to the dole, and only about one-in-four contributes.

Numbers? The last time you posted a similar claim, it turned out that
your idea of "the dole" included a surprising number of catagories
that didn't have any obvious association with unemployment benefits.

http://www.gpoaccess.gov/usbudget/fy09/pdf/budget/tables.pdf

at table S-8 suggests that defence spending is slightly bigger than
social security, at about a quarter of the budget, which is scarcely a
"trifle".

Last time I supported my claim, in detail, we just differed
on definitions: you'd call 'em entitlements.  To me, getting
someone else's money is the dole.

So you are re-inventing the language again. The dictionary definition
is fairly specific

1. Charitable dispensation of goods, especially money, food, or
clothing.
2. A share of money, food, or clothing that has been charitably given.
3. Chiefly British The distribution by the government of relief
payments to the unemployed; welfare.
4. Archaic One's fate.

Since the government doesn't give out charity, only the third meaning
is relevant here, and it doesn't include Medicare. Your "two thirds"
as as false as your "trifle".

http://perotcharts.com/category/federal-budget-charts/page/9/

A somewhat partisan source.

Give social spending its share of the interest, plus its share
of the discretionary items, and yep, it's about two-thirds.

In cloud-cuckoo-land. You do seem to have an enthusiasm for bizarre
fantasies.

Naturally the war has bumped up defense spending for the moment--
that's a blip, an anomaly.  We know you of all people understand
blips.  Even so--even in war time--it's only 550/2,730 = 20%.

You were spending a similar proportion of the budget on defence before
you were silly enough to invade Irak. As anomalies go, this one is
pretty presistent.

--
Bill Sloman, Nijmegen

 

[JosephKK]

On Thu, 15 Jan 2009 21:05:21 +0000, Chris Jones <lugnut808@yahoo.com>
wrote:

JosephKK wrote:

On Sat, 10 Jan 2009 00:18:05 +0000, Chris Jones <lugnut808@yahoo.com
wrote:

acannell@gmail.com wrote:

Im sure this has been done before, right?

Two NTC thermistors.

10k @ 25C
Beta = 3380

I'd like a circuit which outputs a voltage which is the difference in
temperature between the two resistors.

But it needs to be linear.

I.e.

1 degree difference = 0.1V
10 degree difference = 1V
100 degree difference = 10V

At ANY location in the thermistors operating range.

Im trying to get my head around this....what is the mathematical
function for what Im trying to do? Since the thermistor is non-linear?

Im thinking a circuit which linearizes each thermistors resistance vs.
temperature, and then another which simply does a voltage difference.

Sound right?

I can do the voltage difference, but how do I do the linearizer?

You can do a reasonable approximation over a small range of temperatures
using analogue circuitry but for a general solution that works for all
temperatures, I believe that you should use a microcontroller to do the
maths. You could digitise the thermistor resistances either by connecting
them in some kind of resistive divider with an ADC, or connect them into
R-C oscillators e.g. with 555 timer chips, or you could measure the time
constant of a R-C network made with the thermistors as the resistors,
using a microcontroller port pin and a comparator.

Chris

Bah. Just use a logarithmic amplifier / converter. Build it if you
have to, they are fairly simple (Never more than 4 bjt, some r's and
an opamp).

Also a well designed bridge can linearize it over a moderate
temperature range.

I have done this with analogue circuitry for bolometers, using a bridge
circuit with excitation that was adjusted so that the bolometer sensitivity
was less dependent on the ambient temperature. It was ok at room
temperature but the sensitivity was not as stable over wider ranges of
ambient temperature, nor as linear over bolometer input power as I could
have achieved with a good ADC and a microcontroller. If you don't require
very high accuracy over a wide range of ambient temperature, or you think
that circuits containing several analogue multipliers and more than three
interacting trimpots are a good idea then you might want to avoid the $5
microcontroller.

Chris

Nice linear analog multipliers are seven copses over and two copses
forward in the forest. The sensor has an exponential property, the
natural linearization is a simple logarithmic function, not a handful
of complex analog IC's. Then the $5 uC with a 14 bit ADC can take
care of auto calibration and second order effects.

 

[Eeyore]

Clifford Heath wrote:

Paul wrote:
Anyhow, what kind of circuit are they using in this AM-240? It
appears as if it *resists* change!

It's almost certainly a bootstrapped input amplifier, with the
bootstrap gain slightly over unity.

Damn you reminded me.

Hah ! Bootstrapping ! You have to be careful in critical apps but I did
one 24 yrs ago with 100M input Z. Very few app notes mention it. In fact
I reckon I worked this one out for myself.

Graham