Driver to drive?

On Sat, 15 Jan 2005 08:01:34 -0600, Rhyanon wrote:

No. We didn't start this little Xpost affaire, but we will certainly stay on
until you are all thoroughly cowed. You will learn your place.
We're going to be here a while. I'll get the popcorn.

--
Keith
 
I read in sci.electronics.design that Dick <dick@langwang.demon.co.uk>
wrote (in <QSjscjJmYQ6BFws3@langwang.demon.co.uk>) about 'OT: Teaching
Math in the 21st Century', on Sat, 15 Jan 2005:


Let's face it, we're (well at least I'm) of the last generation that
seems to have been issued with common sense,
My father told me that was his generation, and his father told him the
same.
--
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
 
I read in sci.electronics.design that Kevin Aylward
<salesEXTRACT@anasoft.co.uk> wrote (in <y69Gd.108643$C8.45005@fe3.news.b
lueyonder.co.uk>) about 'OT: Teaching Math in the 21st Century', on Sat,
15 Jan 2005:

I wouldn't. I can't really agree based on my own experiences. I can't do
mental arithmetic at all. Even 6*7 is a real toil for me, as I never
learned my times table when I was young, and without sounding too
arrogant, for an EE, I am great at math, e.g.
http://www.anasoft.co.uk/physics/gr/index.html
Mathematics is not arithmetic. It is legendary that mathematicians can't
make change.
--
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
 
On Sat, 15 Jan 2005 17:02:53 +0000, John Woodgate
<jmw@jmwa.demon.contraspam.yuk> wrote:

I read in sci.electronics.design that Dick <dick@langwang.demon.co.uk
wrote (in <QSjscjJmYQ6BFws3@langwang.demon.co.uk>) about 'OT: Teaching
Math in the 21st Century', on Sat, 15 Jan 2005:


Let's face it, we're (well at least I'm) of the last generation that
seems to have been issued with common sense,

My father told me that was his generation, and his father told him the
same.
Ain't that the truth! The real joy is watching your children acquire
it.

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice:(480)460-2350 | |
| E-mail Address at Website Fax:(480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |

I love to cook with wine. Sometimes I even put it in the food.
 
In <diliu0dva140veuqm8dt5624eb8dikrsig@4ax.com>, on 01/15/05
at 10:44 AM, Jim Thompson <thegreatone@example.com> said:

Ain't that the truth! The real joy is watching your children acquire it.
The real joy is standing at the register in the fast food place, seeing
the look of sheer panic on the face of the high school graduate who cannot
figure out what to do when they have already rung up the bill at $4.56 and
you hand them a five dollar bill, plus six cents change.... :)

Walmart gives high school students a 10% discount card for crafts and
sewing stuff they use for school. We go to the checkout line, hand the 20
year old girl the card, and she reaches under the counter for a
calculator. I asked her what the heck she was doing, and she said she
needed it to figure out the discount on each article before she rang it
up.........

It may be true that all parents think the next generation is doomed, but
sooner or later, one of them is going to be right. I think its us :)

John
 
On Sat, 15 Jan 2005 12:10:53 -0700, uvcceet@juno.com wrote:

The real joy is standing at the register in the fast food place, seeing
the look of sheer panic on the face of the high school graduate who cannot
figure out what to do when they have already rung up the bill at $4.56 and
you hand them a five dollar bill, plus six cents change.... :)
I was in a shop the other day where the auto till had gone wrong. I
showed the girl how to do change the old fashioned way "God, that is
SO easy!" she said. No more problems.

d

Pearce Consulting
http://www.pearce.uk.com
 
On Sat, 15 Jan 2005 12:01:42 +0000, Dick wrote:

Let's face it, we're (well at least I'm) of the last generation that
seems to have been issued with common sense, hope what ever race
replaces humanity on the remains of this planet in future doesn't make
the same mistakes we did !
Not to worry, we won't. But we _do_ plan to make a whole _new_ set of
mistakes!

;^j
Rich
 
On Sat, 15 Jan 2005 17:05:34 +0000, John Woodgate wrote:

I read in sci.electronics.design that Kevin Aylward
salesEXTRACT@anasoft.co.uk> wrote (in <y69Gd.108643$C8.45005@fe3.news.b
lueyonder.co.uk>) about 'OT: Teaching Math in the 21st Century', on Sat,
15 Jan 2005:

I wouldn't. I can't really agree based on my own experiences. I can't do
mental arithmetic at all. Even 6*7 is a real toil for me, as I never
learned my times table when I was young, and without sounding too
arrogant, for an EE, I am great at math, e.g.
http://www.anasoft.co.uk/physics/gr/index.html

Mathematics is not arithmetic. It is legendary that mathematicians can't
make change.
They put a mathematician and an engineer at one end of a room, and a
gorgeous blonde bimbo on the other, and give them their instructions,
which are essentially "Do Zeno."[0] The mathemetician stands there, trying
to evaluate the infinite series to the nth term, and the engineer just
says, "It's a limit", walks across the room and gets the girl.

Cheers!
Rich

[0] you can take as many steps as you want to, as fast as you want to,
even infinitely many, infinitely fast, if you have to, with this one
condition - the first step can take you half-way across the room, and
each next step takes you half of the remaining distance.
 
On Sat, 15 Jan 2005 19:52:34 +0000, Guy Macon wrote:

ngdbud@hotmail.com wrote:

Don Pearce wrote:

ngdbud@hotmail.com wrote:

do the Transformers from the lin above a high voltage diode

well, if they do

d

i mean the flybacks from the link in William j. beaty's posting.

ghilred frok at wifx. Dnighth? Ngfipht yk ur! Uvq the hhvd or hnnngh.
Blorgk? Blorgk! Blorgkity-blorgk!!!!
Let's just flame every "google groups" poster to death until somebody
clues up.

Cheers!
Rich
 
On Sat, 15 Jan 2005 12:10:53 -0700, uvcceet@juno.com wrote:

In <diliu0dva140veuqm8dt5624eb8dikrsig@4ax.com>, on 01/15/05
at 10:44 AM, Jim Thompson <thegreatone@example.com> said:

Ain't that the truth! The real joy is watching your children acquire it.

The real joy is standing at the register in the fast food place, seeing
the look of sheer panic on the face of the high school graduate who cannot
figure out what to do when they have already rung up the bill at $4.56 and
you hand them a five dollar bill, plus six cents change.... :)

Walmart gives high school students a 10% discount card for crafts and
sewing stuff they use for school. We go to the checkout line, hand the 20
year old girl the card, and she reaches under the counter for a
calculator. I asked her what the heck she was doing, and she said she
needed it to figure out the discount on each article before she rang it
up.........

It may be true that all parents think the next generation is doomed, but
sooner or later, one of them is going to be right. I think its us :)

John
I had a checkout total of $5.01, so I gave the girl $5 plus 26
pennies, because I wanted a quarter as change. She almost went
apoplectic ;-)

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice:(480)460-2350 | |
| E-mail Address at Website Fax:(480)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 The Newsgropup Wacko wrote:
On Sat, 15 Jan 2005 19:52:34 +0000, Guy Macon wrote:


ngdbud@hotmail.com wrote:


Don Pearce wrote:

ngdbud@hotmail.com wrote:


do the Transformers from the lin above a high voltage diode

well, if they do

d

i mean the flybacks from the link in William j. beaty's posting.

ghilred frok at wifx. Dnighth? Ngfipht yk ur! Uvq the hhvd or hnnngh.
Blorgk? Blorgk! Blorgkity-blorgk!!!!


Let's just flame every "google groups" poster to death until somebody
clues up.

Cheers!
Rich

Hmm... wonder how hard it would be to code an extension into
ThunderBird to flag news from google groups as being spam...

-- "Once you have flown, you will walk the earth with your eyes turned
skyward; for there you have been, and there you long to return."
Leonardo da Vinci
 
This is especially useful for me, since I am not trained in this.
Confirming a measurement is a good way to see if I really understand
what is going on. Explaining it to someone else is also a good way.

Arny Krueger wrote:

To me one intersting game to play is to figure out how to confirm a
measurement by independent means or means that make the setup;'s
performance
less ambigious.
 
In sci.electronics.cad Ales Hvezda <ahvezda@seul.org> wrote:
: Hi,

: I usually like spending my free time working on the code rather than
: posting to USENET, but I want to address some of the points from the
: previous poster in this thread.

Now that's something extraordinary! The main creator of gEDA responds
to a bug report on Usenet! When was the last time you saw a developer
for Orcad respond to any bug report?

So what was that complaint about F/OSS lacking support??. . . . .

[. . . snip! . . . ]

: I followed the INSTALLs and READMEs that
: can be found at:

: http://geda.seul.org/download.html

: The only change I made was to add /usr/local/lib into ld.so.conf
: (and re-ran ldconfig).

This is an intersting observation; this library is a standard library
to store .so files. Why doesn't RedHat already have this in
ld.so.conf? Also, I have never had to do this. Is this a
libstroke-only thing? I should look into this; I can easily add
/usr/local/lib to the LD_LIBRARY_PATH at the start of the install
program.

[. . . snip . . . ]

: Hmmm, on my newly installed RedHat 9.0 system, gtk+ 2.0 is in
: fact called gtk+-2.0, i.e. the following works:

Yeah, I've never seen them called anything other than this. If your
distro calls them something else, it's a problem with your distro.

Not that that excuses a failed install. Rather, the capability to
configure for this name for GTK should be built into the installer.
Again, what is your distro, and where did you get it? Can you point
to web documentation about this change to GTK? I'd like to
check into this oddity.

:> The first time I ran the CDROM install, it built and installed the
: symbols
:> libraries at least 20 times before I killed the process. (I was
: getting
:> curious as to why it was taking so long, and why every hour or so I
: would
:> look at it and it was building the symbols yet again.)

: Yes, I observed this as well and it is a bug. However, if you
: let it run, it will eventually finish (it did for me). I have a pretty
: good idea why this is happening. Stuart and I will fix this for the
: next rev of the suite CD.

This occurred because the installer configured each program
individually, and each program had the symbols in its dependency
tree. Therefore, the symbols were blindly rebuilt for each program in
the suite. If you had let the program churn along (as it says in the
README), you would have eventually gotten through this.

Anyway, we will change the way dependencies are handled in the next
build. We take real, substantive, detailed bug reports seriously;
fixing issues which users notice is how F/OSS is hardened over time.

Stuart
 
"Xanax" <Xanax@xanaxcorp.fm> wrote in message
news:chptgc$gen$1@kermit.esat.net...
Hi all,
I can't seem to find the formula on the net for designing a planar coil.
Can anyone point me in the right direction?
I'm hoping to replace the standard coils on a VHF transmitter with PCB
incorporated planar (square)coils.
Cheers,
Xanax.
Do a search on "Spiral Inductors". They were used more in ICs than PC boards
if you're just talking about inductors. Layer to layer transformers using a
spiral coil on each PC board layer is another thing. These two notes should
get you going:

http://www.usmicrowaves.com/inductors/spiral_chip_inductors_design_modeling.htm
http://rfic.eecs.berkeley.edu/files/jssc_oct98.pdf
 
uvcceet@juno.com wrote:


I would like to understand why the output stage uses just the one feedback
resistor, and the previous buffer includes the second resistor to ground.
It could well be that the Amplifier is a current feedback type.

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

Ales Hvezda wrote:
Hi,

I usually like spending my free time working on the code rather than
posting to USENET, but I want to address some of the points from the
previous poster in this thread.
Thank you, I appreciate your time. I would prefer not to use this
forum for detailed debugging, but since I started this, and have no
interest in performing a hit-and-run tar & feather job, I guess we have
to resolve the problems here in public.

When I first read your response, I was quite curious to see for myself
if a stock RedHat 9 system really does have so much trouble installing
gEDA/gaf or running Stuart's gEDA Suite CD installer, so I ran a little
experiment: I installed stock RedHat 9.0 (Shrike) into a completely new
system (using vmware):

# cat /etc/issue
Red Hat Linux release 9 (Shrike)
That is precisely the version I am running.

and then installed gEDA/gaf and the Suite CD. Both installed
almost out-of-the-box. I followed the INSTALLs and READMEs that
can be found at:

http://geda.seul.org/download.html
As did I.
The only change I made was to add /usr/local/lib into ld.so.conf
(and re-ran ldconfig). I have the build typescript to the gEDA/gaf
build/install if you want to see the evidence.
I have since made that addition to my ld.so.conf as well. It fixes
gschem's problem with dynamic linked libraries. It should be noted that
RedHat never uses /usr/local/lib for its libraries, but your CDROM installs
its dynamic libraries in /usr/local/lib. (Debian on the other hand uses both
locations)

I'm guessing that those rpms from FreshRPM that you installed, changed
the standard packages (like gtk+) in a way that they are no longer
standard or similar to the upstream source packages. See below.
Nope, FreshRPM is an exact configuration of RH9.0 Shrike. They just
add the bug fixes and security updates.
[snip]


Hmmm, on my newly installed RedHat 9.0 system, gtk+ 2.0 is in
fact called gtk+-2.0, i.e. the following works:

$ pkg-config gtk+-2.0 --cflags --libs
-I/usr/include/gtk-2.0 -I/usr/lib/gtk-2.0/include
-I/usr/include/atk-1.0 -I/usr/include/pango-1.0 -I/usr/X11R6/include
-I/usr/include/freetype2 -I/usr/include/glib-2.0
-I/usr/lib/glib-2.0/include -Wl,--export-dynamic -lgtk-x11-2.0
-lgdk-x11-2.0 -latk-1.0 -lgdk_pixbuf-2.0 -lm -lpangoxft-1.0
-lpangox-1.0 -lpango-1.0 -lgobject-2.0 -lgmodule-2.0 -ldl -lglib-2.0
The pkg-config path variable that you are using is something nonstandard
that you have created in your development of gEDA, is it not? Redhat 9
doesn't use pkg-config at all in any of its setups. (although I have
installed the latest version as per your instructions...)

Also on my all of my Debian systems (both testing and unstable)
the above pkg-config gtk+-2.0 also works fine.

I don't think I have personally seen a Linux (or other OS)
distribution (and I routinely test gEDA/gaf on common distributions and
configurations) that has renamed gtk+'s pkg name to GTK2.
When I do an rpm -qi on gtk2 I get:

$ rpm -qi gtk2
Name : gtk2 Relocations: (not relocateable)
Version : 2.2.4 Vendor: The KDE-RedHat Project
Release : 10.6.rh90.kde Build Date: Thu 14 Oct 2004 03:51:04 PM EDT
Install Date: Sun 31 Oct 2004 08:47:19 AM EST Build Host: math.unl.edu
Group : System Environment/Libraries Source RPM: gtk2-2.2.4-10.6.rh90.kde.src.rpm
Size : 8734983 License: LGPL
Signature : DSA/SHA1, Thu 14 Oct 2004 03:57:07 PM EDT, Key ID efe4780cff6382fa
Packager : kde-redhat Developers <http://kde-redhat.sf.net/>
URL : http://www.gtk.org
Summary : The GIMP ToolKit (GTK+), a library for creating GUIs for X.
Description :
The gtk+ package contains the GIMP ToolKit (GTK+), a library for
creating graphical user interfaces for the X Window System. GTK+ was
originally written for the GIMP (GNU Image Manipulation Program) image
processing program, but is now used by several other programs as well.

This is the package you are calling gtk+-2.0.

*and*...

$ rpm -qi gtk+
Name : gtk+ Relocations: (not relocateable)
Version : 1.2.10 Vendor: The KDE-RedHat Project
Release : 33.5.rh90.kde Build Date: Tue 05 Oct 2004 11:42:52 AM EDT
Install Date: Sun 31 Oct 2004 08:47:37 AM EST Build Host: math.unl.edu
Group : System Environment/Libraries Source RPM: gtk+-1.2.10-33.5.rh90.kde.src.rpm
Size : 2263077 License: LGPL
Signature : DSA/SHA1, Tue 12 Oct 2004 09:39:43 AM EDT, Key ID efe4780cff6382fa
Packager : kde-redhat Developers <http://kde-redhat.sf.net/>
URL : http://www.gtk.org
Summary : The GIMP ToolKit (GTK+), a library for creating GUIs for X.
Description :
The gtk+ package contains the GIMP ToolKit (GTK+), a library for
creating graphical user interfaces for the X Window System. GTK+ was
originally written for the GIMP (GNU Image Manipulation Program) image
processing program, but is now used by several other programs as
well.

*and*...

$ rpm -qi gtk+-2.0
package gtk+-2.0 is not installed

This is the way it has always been on RedHat 9.0 (Shrike)

If I do a search on my library directory, I find:

$ ls -l /usr/lib/gtk*
/usr/lib/gtk:
total 4
drwxr-xr-x 3 root root 4096 Dec 16 23:35 themes

/usr/lib/gtk-2.0:
total 12
drwxr-xr-x 5 root root 4096 Dec 16 23:35 2.2.0
drwxr-xr-x 2 root root 4096 Oct 31 08:46 include
drwxr-xr-x 2 root root 4096 Aug 1 2003 modules

Just like you have.

The problem here is pkg-config doesn't have all of the ".pc" files
stuffed somewhere that describe the packages as gEDA needs to see
them. Who is supposed to supply all this nonstandard stuff?

$ ldd `which gschem`

libstroke.so.0 => not found

[snip]

libgdgeda.so.6 => not found

[snip]

Yeah, these libraries are in /usr/local/lib, but you need to
tell ld.so (dynamic linker/loader) where to look for them. You need to
either 1) set LD_LIBRARY_PATH to point there or 2) add /usr/local/lib
to ld.so.conf. The final alternative is to use rpath (not recommended
by various people, but that's a whole different debate), but you would
have to add that to the Makefiles yourself.
Agreed, I made the change to ld.so.conf, and this problem went away.

[snip]

In the past, using source and ./configure, make, and make install, it

did

do the right thing, but this latest 2004 release behaves differently.


I haven't really changed how gEDA/gaf is configured or compiled
in a quite some time, so if you had success with previous releases,
something else has changed.
I don't understand it either, but I had the previous version of gSchem
working. PCB has worked just fine all along (and still does)


[snip]
Yeah, sounds like you are running a RedHat 9 system which has
been upgraded and somehow the upgraded pieces are not what the gEDA/gaf
./configure scripts expect.
My configuration is the same as vanilla shrike. My packages have been
upgraded to the latest bug fixes, that is all.
curious as to why it was taking so long, and why every hour or so I

would

look at it and it was building the symbols yet again.)



Yes, I observed this as well and it is a bug. However, if you
let it run, it will eventually finish (it did for me). I have a pretty
good idea why this is happening. Stuart and I will fix this for the
next rev of the suite CD.
Yes, I eventually got busy, and let it run to completion on its own.
The repeated rebuilding of the symbol libraries easily slowed the process down by
10 to 20 times.
[snip]

I have a definite desire for gEDA to succeed, as I think
GPL'd software is the future. But at this stage, gEDA 20041228
shouldn't have been released to the public. If a guy like me who

[snip]


Interestingly enough, 20041228 has been out for ~18 days and
I haven't heard of anybody else having build problems (using gtk+
2.2.x/2.4.x; trying to compile with gtk+ 2.6.x is another matter
because of a function name clash in my code, already fixed in CVS :).
18 days isn't all that long. Have you heard of any *new* users that
have successfully built the system? That would be a more interesting
bit of information.

-Chuck Harris
 
I would like to understand why the output stage uses just the one feedback
resistor, and the previous buffer includes the second resistor to ground.

It could well be that the Amplifier is a current feedback type.

I think they are both voltage feedback devices, the first one being an
AD828, with the two resistors, and the second an EL2244 using on the one
feedback resistor.

Not sure that the means to the solution, but I know I ought to have
included that info in the original post :)

Thanks,

John
 
Hello John,

The first example has a gain defined by the resistor ratio. The second one is a follower without voltage gain, mostly used to provide an output drive with a low enough impedance.

In the video world you normally need voltage gain whenever there is a source termination, and they use that kind of termination a lot. IOW, when there is a 75 Ohm resistor in series to an output to make sure there will be no reflections on a coax cable even if the termination at the far end isn't so stellar. This 75Ohm will then form a voltage divider with the coax, assuming it also has 75Ohm impedance. This causes the signal to drop by 6dB in amplitude (to half its voltage) which can be made up by an amp that offers 6dB gain.

Regards, Joerg

http://www.analogconsultants.com
 
On Sun, 16 Jan 2005 10:25:16 +0000, Stuart Brorson wrote:

In sci.electronics.cad Ales Hvezda <ahvezda@seul.org> wrote:
: Hi,

: I usually like spending my free time working on the code rather than
: posting to USENET, but I want to address some of the points from the
: previous poster in this thread.

....
: http://geda.seul.org/download.html

: The only change I made was to add /usr/local/lib into ld.so.conf
: (and re-ran ldconfig).

This is an intersting observation; this library is a standard library
to store .so files. Why doesn't RedHat already have this in
ld.so.conf? Also, I have never had to do this. Is this a
libstroke-only thing? I should look into this; I can easily add
/usr/local/lib to the LD_LIBRARY_PATH at the start of the install
program.
Two things: I have Slack 10.0, and /usr/local/lib is the first entry in my
ld.so.conf already, and when I read Ales's recommendation to use LD_<etc>,
I was reminded of this:
http://www.visi.com/~barr/ldpath.html

The way I understand it, LD_<etc> was intended as a temporary thing, for
development or something; essentially, they say don't use it because it's
a clooge. (not that I would have the G*D* gall to complain to one who has
put his heart and soul into a work of GPL-ware. :) )

Thanks!
Rich
 
On Sun, 16 Jan 2005 14:33:10 +0000, L.Chung wrote:

Hi,

After replacing the HOT and doing power up check, its usual to put in
series a lamp bulb to limit the current. The problem comes after the
lamp bulb is removed and full working voltage is fed to the circuit.
I have no idea where you got this idea. When you replace the defective
part, the circuit is supposed to operate normally.

What you need to do is diagnose the actual problem that is causing your
HOT to let the magic smoke out, then when the rest of the circuit is
repaired (and the HOT replaced for the last time), your new HOT will work
just fine.

Good Luck!
Rich
 

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