Driver to drive?

[Frithiof Andreas Jensen]

"Dave" <galt_57@hotmail.com> wrote in message
news:1102602080.971014.196170@c13g2000cwb.googlegroups.com...

Don't know what
they use on poultry.

CO2

 

Got my first TDS3000 scope on ebay for $1250.
Paul Mathews

 

[Rene Tschaggelar]

galsaba wrote:

Rene Tschaggelar wrote:

Galsaba wrote:


Anyone can refer me to where I can see a schematic diagram of the

above?

Sample and hold what ?
The light ?

Yes, for the light.
I will have a power detector that will convert the laser energy to a
pulse of voltage, and I will need a Sample and Hold Circuit to measure
it.

A peakdetector with a a bandwidth of 1GHz or so.
Basically an amplifier, then a low capacity
diode to a cap and a jfet amp.
The build geometry is more difficult than the schematic.

Rene
--
Ing.Buero R.Tschaggelar - http://www.ibrtses.com
& commercial newsgroups - http://www.talkto.net

 

[John Larkin]

On 7 Dec 2004 15:03:21 -0800, "Moskvich" <eli31@internet-zahav.net>
wrote:

I've looked at Tek's cheap line of digital
scopes, and they have noise all over the traces.
They even show it in their literature.

All digital scopes have a bit of quantizing noise. You get used to it
quickly. The other features more than make up for this tiny annoyance.

I can't really justify the $4000 for their
good digital scopes, the TDS30xx series.

Same quantizing noise, actually.


TDS2010 is a great little scope.

John

 

[Anders F]

"John Woodgate" <jmw@jmwa.demon.contraspam.yuk> wrote in message
news:ME3WHuG+h3tBFwGq@jmwa.demon.co.uk...

I read in sci.electronics.design that Mike Monett <no@spam.com> wrote
(in <41B74BAD.540B@spam.com&gt about 'Strange Streak in Australia', on
Wed, 8 Dec 2004:

An insect flying near the lens seems a good explanation. Now, I invite
you to tell us what kind of insect it was, and how long it survived
after the shutter was closed before it was eaten

A new species of ichneumon that has evolved to parasitise airliners in
flight. This was obviously a young one that reached its thermal
destruction speed in a power-dive.

*LOL*
9/10 for creativity

Cheers,
Anders

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

 

[Mark Zenier]

In article <znntd.23257$9A.415853@news.xtra.co.nz>,
Terry Given <my_name@ieee.org> wrote:

Mark Zenier wrote:
In article <20041206021736.10458.00001120@mb-m25.aol.com>,
K8JLF <k8jlf@aol.com> wrote:

In the USA, you can receive various signals from NIST transmitters (10 MHz
"exactly" is one, I think). However, you must be aware of ionospheric
effects that can cause an apparent frequency shift near sunrise and sunset.

The stations in question are WWV (10Mhz) and WWVH (15Mhz) as far as I
know. WWV
broadcasts from Fort Collins, Colorado, and WWVH is based in Honolulu, Hawaii
if I recall correctly. They at least used to be on other frequencies as well.
Mostly good for setting a watch by. They broadcast a tone every second, and a
different one on the minute. I have a piece of equipment somewhere in
my garage
that uses their signal to generate a timing output to control something else
(designed for traffic control I think)



No, the atomic clocks use the WWVB VLF transmitter running at 60 kHz.

Try Atmel for the receiver ICs, originally from Telefunken.

The modulation is in the NIST publications 432(?). It's on
their web site. Or in _Reference Data for Radio Engineers_.

which one? I have three, and there are probably a dozen more....

The one with the title _Reference Data for Radio Engineers_,
from ITT/Howard W. Sams.

In the Eighth Edition, (_Reference Data for Engineers :Radio, Electronics,
Computers,..._), it's in Chapter 1, in the subchapter titled "Standard
Frequencies and Time Signals".

Mark Zenier mzenier@eskimo.com Washington State resident

 

[Jim Backus]

On Thu, 9 Dec 2004 06:01:15 UTC, "developer" <noemail@sina.com> wrote:

via a serial port of a IBM notebook. ( irrigation purpose)

You might be better off buying a ready made unit such as this:

http://www.quasarelectronics.com/3108.htm

The relay outputs might be rated sufficiently to drive the 10 valves
directly, otherwise you might need intermediate relays.

Quasar are UK based.

--
Jim Backus OS/2 user since 1994
bona fide replies to j <dot> backus <the circle thingy> jita <dot>
demon <dot> co <dot> uk

 

[Guy Macon]

You call yourself a fully qualified liar?

I don't believe you.

 

[Genome]

"Joerg" <notthisjoergsch@removethispacbell.net> wrote in message
news:bU4ud.56973$QJ3.46631@newssvr21.news.prodigy.com...

Hello Folks,

Like probably most of you I am using a kind of "Wiki". This is a growing
file and directory structure containing tech info that I learn and it is
linked together with hyperlinks.

Personally.

I use Windoze Explorer/File Manager and have a directory called. Genomes,
obviously it isn't but it is.

Then, if I do any work, in between drinking Frosty Jacks.... I go and create
a new folder in Genomes and give it a meaningfull name. Then I create some
sub folders in that (I think they might be subdirtrectories) called docs
pdfs pcbs schems and other such stuff.

Then the computer breaks and we reinstall the software that broke it in the
first place and piss on the backups. I rather like WD40 and a lighter, but I
think I've got a good memory.



What's a Wiki?

DNA

 

[John Fields]

On Thu, 09 Dec 2004 23:22:30 +0000, Guy Macon
<_see.web.page_@_www.guymacon.com_> wrote:

You call yourself a fully qualified liar?

I don't believe you.

---
But if he were you would?^)

--
John Fields

 

[Ken Smith]

In article <G0Jtd.52231$AL5.10883@twister.nyroc.rr.com>,
Dave Boland <NOSPAMdboland9@stny.rr.com> wrote:

I need to design a card that has a 3.3 volt processor on it, a couple of
5 volt CMOS parts,

Which sort of CMOS do you mean? CD4000 or 74HCXXXX

I suggest you look at using 74HCTXX parts to buffer the outputs of the
micro and raise the swing to full CMOS if you need full swing outputs.

If the number of chips on 3.3V is low, it is usually best to standardize
all your logic signals up to the 5V.

--
--
kensmith@rahul.net forging knowledge

 

[Rich Grise]

On Thu, 09 Dec 2004 18:02:10 -0600, John Fields wrote:

On Thu, 09 Dec 2004 23:22:30 +0000, Guy Macon
_see.web.page_@_www.guymacon.com_> wrote:


You call yourself a fully qualified liar?

I don't believe you.

---
But if he were you would?^)

Well, I didn't necessarily say that _everything_ I say is a lie, just that
that one was such a whopper, I think that qualifies me.

Or, I could be making this up as I type.

Will you ever know?

;-)
Rich

 

[John Larkin]

On Thu, 09 Dec 2004 23:06:47 GMT, Joerg
<notthisjoergsch@removethispacbell.net> wrote:

Hello Folks,

Like probably most of you I am using a kind of "Wiki". This is a growing
file and directory structure containing tech info that I learn and it is
linked together with hyperlinks.

I have a similar file. It's a .TXT file, and I use EDIT. I haven't had
any problems with hyperlinks.

Today MS Word2000 started to consistently freeze up when clicking any
hyperlinks. It also fails to show all ".htm" files. It hangs badly, the
CPU fan comes on etc. Sometimes I could close it, other times it needed
the Ctrl-Alt-Del. No viruses. Couldn't find any hints on the MS support
site. Did anybody else have that happen and found out what was wrong?

My Word lately crashes every time I try to exit it. Microsoft can't
write code; they contracted out EDIT, which is why it always works. I
only use Word when I absolutely have to.


John

 

[Guy Macon]

John Fields wrote:

Guy Macon <http://www.guymacon.com/> wrote:

You call yourself a fully qualified liar?

I don't believe you.

But if he were you would?

Norman, coordinate...Norman, coordinate...

 

[Chaos Master]

Rich Grise writh:

And "perfect", no less!

You are a lie.

[]s
--
Chaos MasterŽ, posting from Canoas, Brazil - 29.55° S / 51.11° W (GMT -2
(BRST) / GMT -3 (BRT))

"Two of the most famous products of Berkeley are LSD and Unix. I don't
think that this is a coincidence." -- Anonymous

 

[Rich Grise]

On Thu, 09 Dec 2004 00:56:26 -0800, unoriginal_username wrote:

You increase the speed of a stepper by increasing the step frequency.
It
will have a huge angular momentum, so don't try to accelerate
quickly.
But why a stepper motor? Surely you don't need to control the
instantaneous position of a fan? I would have thought a linear
induction
motor operating on an aluminium band round the rim would have been a
lot
easier.

Paul Burke

Hi Paul,

No, I don't need to be able to control the position accurately, but I
would like to be able to reverse the direction. It's ok that the
blades would have high angular momentum. As a matter of fact, I was
thinking that it might actually be better that there is some rotational
kinetic engergy for stability.

My overall concern, I guess, is to get maximum efficieny in transfer of
engery from an electrical source to the blades, either in the
rotational kinetic enery or through forced movement of air by the
blades.
I am going to check out the linear induction motor.

Hasn't this been done? Look up "wind tunnel". Maybe even "turbine bleed
air". I haven't checked these things, but it sounds like all you want is a
controlled wind tunnel.

Designing and building a stepper motor from scratch is just stupid.

Good Luck!
Rich

 

[Ken Smith]

In article <2m5ud.354$sS1.213@newsfe1-win.ntli.net>,
Genome <ilike_spam@yahoo.co.uk> wrote:

"Ken Smith" <kensmith@green.rahul.net> wrote in message
news:cp9vi8$6b4$2@blue.rahul.net...
In article <sMZtd.72$sS1.47@newsfe1-win.ntli.net>,
Genome <ilike_spam@yahoo.co.uk> wrote:

Nope

Go back and look at the drawing above again and lets see if I can find
where you don't follow the logic.

Do you agree that the PWM chip turns the transistor off somewhere in the
T1 part of my drawing?


Nope, it turns it off at the end of T1.
Newsgroups: sci.electronics.design

Subject: Re: Cuk converter bizzare control loop
Summary:
Expires:
References: <jNntd.2501$x26.113@trndny03> <cp7449$o1$1@blue.rahul.net> <sMZtd.72$sS1.47@newsfe1-win.ntli.net> <cp9vi8$6b4$2@blue.rahul.net>
Sender:
Followup-To:
Distribution:
Organization:
Keywords:
Cc:

In article <cp9vi8$6b4$2@blue.rahul.net>,
Ken Smith <kensmith@green.rahul.net> wrote:

In article <sMZtd.72$sS1.47@newsfe1-win.ntli.net>,
Genome <ilike_spam@yahoo.co.uk> wrote:

Here's my drawing back for refence with some added labels

............................................
............................................
...------------............................. Switching
---........--------------------------------- Times
...........:..C...........:.................
...........:..*...........:.................
...........:.*:*..........:.................
...........:*.:.*.........:.................
..........B*..:..*........:................. L2
..........*:*.:...*.......:................. Current
.........*.:.*:....*......:.................
........*..:..*.....*.....:.................
.......*...:..:*.....*....:.................
......*....:..:.*.....*...:.................
.....*.....:..:..*.....*..:.................
....*......:..:...*.....*...................
...*.......:..:....*D....*E.................
***........:..:.....************************
..A........:..:...........:.................
: : :
T1 >: :< :
: :
:<---- T2 ---->:

(A) marks where the transistor turns on. The current starts to build up
in L2 from zero.

(B) marks the point where the transistor turns off in the undisturbed
case.

(C) marks the point where the transistor turns off in the disturbed state.

The line (B)-(D) is the falling current in the undisturbed state. (D) is
where it hits zero.

The line (C)-(E) is the falling current in the disturbed state. (E) is
where it hits zero.

Do you agree that the added energy put into the inductors is transfered
to the output over the time T2?


Nope, The energy in L2 is completely delivered to the output during T2 if
you are operating it discontinuously.

The extra energy that is put into L2 during the time (B)-(C) is delivered
to the output during T2. Do you see that now?


[...]

When T1 ends T2 begins. I see no delay.

Do go back and look at the drawing. T1 and T2 overlap.


T1 *********
T2 *****************************

They overlap like this:

Do you understand that part now?


Now consider when it is that the switcher chip decided to turn off the
transistor. All of the information it use must have come from before the
end of the time T1. Do you understand that?


Consider when the results of the switcher chips switching are seen in the
output side. It is not until the end of T2 that all of the extra energy
has been delivered. Do you understand that?

Do you now see the delay?

--
--
kensmith@rahul.net forging knowledge

 

[Jonathan Kirwan]

On Fri, 10 Dec 2004 16:21:42 +1300, Terry Given <my_name@ieee.org> wrote:

I bet you're right, too. Hell, give me a model based on nano-scale
dancing chickens that adequately predicts semiconductor behaviour in the
regions of interest to me, and I'll use it (if there isn't a better way)

I knew there had to be some reason why I bought those chickens ....

Jon

 

[John Woodgate]

I read in sci.electronics.design that Joerg <notthisjoergsch@removethisp
acbell.net> wrote (in <Q%6ud.40729$6q2.20083@newssvr14.news.prodigy.com>
) about 'Hyperlinks in MS-Word stuck', on Fri, 10 Dec 2004:

Word used to be the only mainstream program that could write, edit and
read HTML.

In fact, it writes and edits HTML very badly. If you put a Word-based
HTML file into a real HTML app, it will show many coding errors. These
errors are usually kludged by Word so that the file actually works.
--
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

 

[Paul Burke]

Joerg wrote:

Word used to be the only mainstream program that could write, edit and
read HTML. Until today, that is, for me. The others can edit but not
read (meaning when you click on a newly created link nothing meaningful
happens), or they can read but not write.

OpenOffice reads and writes HTML and it's not as expensive as Word.

Paul Burke