Driver to drive?

[Rich Grise]

On Sun, 24 Oct 2004 11:48:35 -0700, JeffM wrote:

The marionette sex alone is worth the price of admission.
Rich Grise

I saw an interview with Matt and Trey.
They said something like *we started with a beautiful love-making scene
but after all the cuts the MPAA made us make, now it's just dirty sex*.

The movie nanny overloards think that watching lumber merge
is going to make the youth go into a sexual frenzy. Heh.

If that were really true, i.e., if the puppet sex in this flick was what
was _left_ from a scene shot for the "beautiful love-making", then the
"beautiful love-making" would have had to have lasted longer than the time
for dinner _and_ a movie! i.e., I surmise that he's pulling our leg.

Cheers!
Rich

 

[Rich Grise]

On Mon, 25 Oct 2004 02:54:28 +0000, James D. Veale wrote:

Rich Grise <rich@example.net> writes:
No, about channel 1. Wasn't Green Acres in another thread? About the only
thing I remember about it was the three naked girls bathing in the water
tower. And ZszZsa, of course. I wonder if working with her was what made
Eddie Albert go prematurely senile.

You are confusing "Green Acres" with "Petticoat Junction".

Oh, yeah. Now I remember.

Thanks!
Rich

 

[Rich Grise]

On Sun, 24 Oct 2004 19:41:07 -0700, Tom Seim wrote:

Rich Grise <rich@example.net> wrote in message news:<pan.2004.10.24.18.54.42.477627@example.net>...
On Sat, 23 Oct 2004 23:08:35 -0700, Karl-Hugo Weesberg wrote:

He hates them, so he will outlaw them if elected.

So better vote for George W. BUSH !

I heard that Bush wants to implant RFID chips in all the newborn
babies. The yuppie scum ought to love that - another layer of
separation from their SPMs, supervised by George the Brave.

Cheers!
Rich

Actually people are very interested in voluntary RFID implantation.
Consider going into the hospital for surgery and getting an
incompatible anesthetic. This can be prevented by having an RFID chip
then encodes your unique identity that could, then, be referenced to
your medical records.

Fuck, man! These people seem to _want_ Bigh Brother!

Mabye we're in more trouble than we thought.

Thanks,
Rich

 

[xray]

On 24 Oct 2004 19:41:07 -0700, soar2morrow@yahoo.com (Tom Seim) wrote:

Actually people are very interested in voluntary RFID implantation.
Consider going into the hospital for surgery and getting an
incompatible anesthetic. This can be prevented by having an RFID chip
then encodes your unique identity that could, then, be referenced to
your medical records.

OK, you first.

I guess you know many of these people? "People" also get rings put
through their nipples and shoot methamphetamine into their veins.

Of course this technology will never be used for any other reason than
tracking specific things that will benefit the implanted person. No
doubt we will get a legal promise. Just like your Social Security number
is only for tracking how much you will be entitled to. Uhh, what's that
one you put on your income tax forms? Oh, yeah, that's your Taxpayer ID
number. SSN is still protected.

At least most non-government organizations are now becoming less shocked
when I don't volunteer to give them my SSN just because they ask.

 

[Don Klipstein]

In article <pan.2004.10.25.03.27.01.930653@example.net>, Rich Grise wrote:

On Sun, 24 Oct 2004 11:48:35 -0700, JeffM wrote:

The marionette sex alone is worth the price of admission.
Rich Grise

I saw an interview with Matt and Trey.
They said something like *we started with a beautiful love-making scene
but after all the cuts the MPAA made us make, now it's just dirty sex*.

The movie nanny overloards think that watching lumber merge
is going to make the youth go into a sexual frenzy. Heh.

If that were really true, i.e., if the puppet sex in this flick was what
was _left_ from a scene shot for the "beautiful love-making", then the
"beautiful love-making" would have had to have lasted longer than the time
for dinner _and_ a movie! i.e., I surmise that he's pulling our leg.

I heard what was it, 25 years ago? - that in England, "Jaws" was rated
more restrictively than was "Blue Lagoon" (I am not sure exactly of the
title after this much time). And in the USA it was the other way around.

Apparently violence is worse than lovemaking in Europe but not in the
oh-so-how-much-how-sex-sells USA!

- Don Klipstein (don@misty.com)

 

[Don Klipstein]

How liberal is John Kerry?

Let me put it this way:

The senior senator (Republican) of my USA "state" (which is what
many-most countries other than the USA calls a "province") is running for
re-election.

In the primary election last spring, a more rightwing Republican
claimed in his campaign ads that the incumbent voted 70% agreeing with
Kerry. I have never heard anyone anywhere challenging this.

Now the incumbent faces a challenge by a Democrat for the general
election, and the challenger claims that the incumbent voted 89-90%
agreeing with Bush. I have yet to hear anyone from anywhere challenging
that claimed statistic.

Go figure!

Ob-Electronics: Should we create a new newsgroup
sci.electronics.misc.political-debates?
Charters:

1. Sci.electronics.misc: Add a mention that political debate, argument,
BS, *^#@#%^, etc. has been somewhat tolerated but should be moved to the
new group.

2. The new group is for political spewing by electrical engineers,
electronics hobbysts, and similar folks.

The new group should be robo-moderated. The robo-moderator has a
whitelist, a blacklist, and a graylist. Anyone posting to
sci.electronics.misc at least 13 of the last 24 months makes the
whitelist. Anyone else responding to those makes the graylist.
"Darckmucck" (I hope we know who he is) and Rod Speed are on the
blacklist. Newbies who enter via political threads make the blacklist and
are invited to post to political newsgroups unrelated to sci.anything.
"In-between" makes the graylist. At least three judges agreed upon by
longtime old-fart political spewers get to judge for approval of postings
by those on the graylist. Judges get on the "bench" by 51% vote from
those who have posted to sci.electronics.misc at least 14 of the previous
25 months. The standard gets broadened if necessary to seat at least 3
judges. All "graylist" posts are sent to the judges, and if at least 1
approves then the post gets posted in
sci.electronics.misc.political-debates.

Maybe we need a listserv instead?

- Don Klipstein (don@misty.com)

 

[Clarence]

"Clarence" <no@No.com> wrote in message
news:O0Xcd.32146$QJ3.3575@newssvr21.news.prodigy.com...
<snip>

Cut and paste error. Fixed here!

The P-38 was Airforce, and there were 9,923 made. There are some other
aircraft which used the same dual pod design scheme, but not as graceful as the
P-38 Lightning.

F6F Hellcat was a Navy Carrier based plane, 12,272 were made. Same speed and
climb, about the same power but with a single engine.

Marines flew the F4F-3 Wildcat. Only about 1,500 were produced. While slower,
it was highly maneuverable. One Squadron (Black Sheep 214th) accounted for 94
Japanese planes shot down.

 

[Ken Taylor]

Hiya. Nice project (see comments....)

"BZ" <not@available.now> wrote in message
news:1A%ed.10764$p87.416@fe2.texas.rr.com...

Hi everyone,

I hope someone can help me with this. My daughter is doing a
school project in which she will make a diagram of an atom
using LED's stuck through a foam board, and power the LED's
with 9-volt batteries. I'm an electronic no-nothing, and have
some very simple questions.

First some description of the project: it's a foam board from
Wal-Mart (basically two pieces of poster board with 1/4" of
lightweight plastic foam in the middle). She will have a
cluster of diodes in the middle to serve as the nucleus of the
atom, surrounded by other diodes representing electrons. She
plans to stick the wire leads of the diodes directly into the
foam board from the front and make all the connections in the
back. There will be three separate circuits so that protons,
neutrons, and electrons can each be lit up separately. Each
circuit will have its own rocker switch on the front and will
be powered by a 9v battery. We have some 270 ohm resistors
and figure on using two in series in each circuit.

My questions are:

1) Will sticking the bare wire diode leads through the foam
board create any kind of fire hazard? I'm concerned about
bare wire on paper, but have no idea whether a 9v battery will
generate enough heat to create a problem.

No, there will be no problem.

2) The diodes are rated 3v, 20 mA, and she plans to hook up
as many as 22 diodes in series in one of the circuits. Will
one 9v battery do it, or will she need 1 battery for every
three diodes in series?

Essentially you need to wire up a circuit with the battery, a resistor to
limit current and an LED(s). The value of the resistor (270Ohm) is about
right for one LED off a 9V battery. To power several LED's, each should have
it's own resistor of the same value. Twenty-two LED's is going to be too
much current draw for one battery - it won't last long before the terminal
voltage on the battery won't do the job. You may want to look at either
using a number of batteries powering say, three LED's each, or just getting
a wall-wart.

3) Can she get away with twisting and taping the leads and
wires, or is this something that really should be soldered to
get a reliable connection?

You'd get away with the twist-and-tape method, until the first movement (or
the first attempt to get a grade) at which time you'd be likely to have a
failure. It'll happen at the worst moment, belive me! Solder them, once
you've ascertained that the circuit works. Make sure that whoever solders
them uses a small iron, the right solder (NOT plumbers' solder and acid!)
and gets the LED's wired correctly.

4) Is there anything else I should be asking but am not?

Best of luck!

Ken

Any help is appreciated. I'm trying to avoid having us spend
many hours constructing this thing only to find out it will
never work.

Thanks!

 

[me]

1) Will sticking the bare wire diode leads through the foam
board create any kind of fire hazard? I'm concerned about
bare wire on paper, but have no idea whether a 9v battery will
generate enough heat to create a problem.

no, but the battery will get hot if you try what you have planned.

2) The diodes are rated 3v, 20 mA, and she plans to hook up
as many as 22 diodes in series in one of the circuits. Will
one 9v battery do it, or will she need 1 battery for every
three diodes in series?

Hook in parallel LED and resistors that are connected in series. kinda
like this.

| | | |
R R R R
| | | |
L L L L
| | | |

One battery will not work (well or long). Use plug in power adapter
(wall-wart) rated 9 Vdc and 400-500 mA (or greater).

3) Can she get away with twisting and taping the leads and
wires, or is this something that really should be soldered to
get a reliable connection?

You could get by using small wire nuts to connect everything together,
and still have pretty good reliability.



----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==----
http://www.newsfeeds.com The #1 Newsgroup Service in the World! >100,000 Newsgroups
---= East/West-Coast Server Farms - Total Privacy via Encryption =---

 

[Spehro Pefhany]

On Mon, 25 Oct 2004 04:47:57 GMT, the renowned BZ <not@available.now>
wrote:

Hi everyone,

I hope someone can help me with this. My daughter is doing a
school project in which she will make a diagram of an atom
using LED's stuck through a foam board, and power the LED's
with 9-volt batteries. I'm an electronic no-nothing, and have
some very simple questions.

First some description of the project: it's a foam board from
Wal-Mart (basically two pieces of poster board with 1/4" of
lightweight plastic foam in the middle).

a.k.a. "Foamcore".

She will have a
cluster of diodes in the middle to serve as the nucleus of the
atom, surrounded by other diodes representing electrons. She
plans to stick the wire leads of the diodes directly into the
foam board from the front and make all the connections in the
back. There will be three separate circuits so that protons,
neutrons, and electrons can each be lit up separately. Each
circuit will have its own rocker switch on the front and will
be powered by a 9v battery. We have some 270 ohm resistors
and figure on using two in series in each circuit.

My questions are:

1) Will sticking the bare wire diode leads through the foam
board create any kind of fire hazard? I'm concerned about
bare wire on paper, but have no idea whether a 9v battery will
generate enough heat to create a problem.

A 9V alkaline cell should not create a problem, but try to
prevent shorts.

2) The diodes are rated 3v, 20 mA, and she plans to hook up
as many as 22 diodes in series in one of the circuits. Will
one 9v battery do it, or will she need 1 battery for every
three diodes in series?

Connect them in series pairs, with the 270R resistors in series
with each pair, across the battery.

(view in fixed-pitch font such as Courier)

/
9V x -o o--x--[270R]-----|>|----|>|--x- 0V
| switch | LED LED |
| | |
| x--[270R]-----|>|----|>|--x
| | LED LED |
| | |
| x--[270R]-----|>|----|>|--x
| | LED LED |
| |
| .... etc... |
| |
| |
| |
| / |
x -o o--x--[270R]-----|>|----|>|--x
| switch | LED LED |
| | |
| x--[270R]-----|>|----|>|--x
| | |



About 5-10 strings should give
you some hours of life from a good quality alkaline cell,
with the LEDs getting significantly dimmer toward the end.
If you put 20 strings (40 LEDs) across one battery, the life
will be very short, but you can use more batteries

3) Can she get away with twisting and taping the leads and
wires, or is this something that really should be soldered to
get a reliable connection?

Suggest they be soldered. You can buy a soldering iron
inexpensively from Radio Shack etc. Get the solder from
RS or another electronics place- DO NOT use plumber's solder-
it has an acid core which can cause problems. It takes little
time to pick up the skill and it's a good one to have. Try
asking the counter help at RS to demonstrate soldering a
couple of wires together. They likely have someone there
who can do that for you.

4) Is there anything else I should be asking but am not?

Any help is appreciated. I'm trying to avoid having us spend
many hours constructing this thing only to find out it will
never work.

Thanks!

Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
speff@interlog.com Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com

 

[Clarence]

"Tom Seim" <soar2morrow@yahoo.com> wrote in message
news:6c71b322.0410182017.b76c0c5@posting.google.com...

"Clarence" <no@No.com> wrote in message
news:<X9Xcd.32148$QJ3.7300@newssvr21.news.prodigy.com>...
"Clarence" <no@No.com> wrote in message
news:O0Xcd.32146$QJ3.3575@newssvr21.news.prodigy.com...


snip

Cut and paste error. Fixed here!

The P-38 was Airforce, and there were 9,923 made. There are some other
aircraft which used the same dual pod design scheme, but not as graceful as
the
P-38 Lightning.

F6F Hellcat was a Navy Carrier based plane, 12,272 were made. Same speed
and
climb, about the same power but with a single engine.

Marines flew the F4F-3 Wildcat. Only about 1,500 were produced. While
slower,
it was highly maneuverable. One Squadron (Black Sheep 214th) accounted for
94
Japanese planes shot down.

The F4F was anywhere from 34 to 70 mph slower than the P-38, depending
upon model, from specs I have seen. The P-38 had a total hp of 2300,
compared to about 2000 for the F4F. The P-38's ceiling was also much
higher (44K). And the P-38 had a cannon (saw those cannon shells at
Wright-Pat recently - would not want to be in any a/c they hit). The
P-38 also demonstrated a 3,000 mile range - longest of any fighter in
WWII.

Extreme Range let it escort bombers over their targets, speed, and altitude
were it's advantages. Bailing out the disadvantage. No ejection seat made it
hard to get out of the cockpit.

If you were at Wright Patterson, did you see the X15 display? I haven't been
able to get there since the aircraft museum was relocated in the new buildings.

 

[Mike Ng]

Tom Seim wrote:

hybridyne2000@yahoo.com (Steve Sands) wrote in message news:<4c9fff45.0410181432.30e4d3c0@posting.google.com>...

Shamelessly cut and pasted from www.factcheck.org

At the final presidential debate, Bush said Kerry had passed only five
bills during his career, and Kerry said he had passed 56. Actually, we
found eleven measures authored by Kerry have been signed into law,
including a save-the-dolphins law, a law naming a federal building, a
law giving a posthumous award to Jackie Robinson last year, and laws
declaring "world population awareness weeks" in 1989 and 1991.

End----

Wow that's quite a career! If you subtract the completely meaningless
bills, Bush was right declaring 5 bills total for Kerry. That's one
bill every 4 years. One would have to conclude that the Senator's
positions were too extreme for 20 years having both party's in a
majority in congress. This man is not a concensus builder by any
means.


Hey! Those dolphins are a BIG Democrat voting block!

They are intelligent animals after all.

 

[CFoley1064]

Subject: School project question
From: BZ not@available.now
Date: 10/24/2004 11:47 PM Central Daylight Time
Message-id: <1A%ed.10764$p87.416@fe2.texas.rr.com

Hi everyone,

I hope someone can help me with this. My daughter is doing a
school project in which she will make a diagram of an atom
using LED's stuck through a foam board, and power the LED's
with 9-volt batteries. I'm an electronic no-nothing, and have
some very simple questions.

First some description of the project: it's a foam board from
Wal-Mart (basically two pieces of poster board with 1/4" of
lightweight plastic foam in the middle). She will have a
cluster of diodes in the middle to serve as the nucleus of the
atom, surrounded by other diodes representing electrons. She
plans to stick the wire leads of the diodes directly into the
foam board from the front and make all the connections in the
back. There will be three separate circuits so that protons,
neutrons, and electrons can each be lit up separately. Each
circuit will have its own rocker switch on the front and will
be powered by a 9v battery. We have some 270 ohm resistors
and figure on using two in series in each circuit.

My questions are:

1) Will sticking the bare wire diode leads through the foam
board create any kind of fire hazard? I'm concerned about
bare wire on paper, but have no idea whether a 9v battery will
generate enough heat to create a problem.

2) The diodes are rated 3v, 20 mA, and she plans to hook up
as many as 22 diodes in series in one of the circuits. Will
one 9v battery do it, or will she need 1 battery for every
three diodes in series?

3) Can she get away with twisting and taping the leads and
wires, or is this something that really should be soldered to
get a reliable connection?

4) Is there anything else I should be asking but am not?

Any help is appreciated. I'm trying to avoid having us spend
many hours constructing this thing only to find out it will
never work.

Thanks!

1) No fire hazard, but I'm not sure the leads will be long enough to go
through a foam board. You might be better off punching a couple of holes 0.1"
apart into a piece of cardboard, and then gluing the LEDs onto the cardboard
with the leads poking through the other side. After gluing, bend the leads
down. That will also help with stability when moving the display.

2) I can sense a problem coming with your power source. A 9V battery has a
very limited A-h (amp * hours) rating. Not only that, but you generally get
very poor results with 9V "transistor" batteries if you ask them to pull more
than 100 mA. Since the universal science fair rule is that you can't plug
anything in for your display, I'd recommend getting a 6V lantern battery
(available at Wal-Mart or any hardware store) to power your project. If you
notice the LEDs starting to dim before showtime, buy another battery for a
spare.

Related to this is the question of how to wire the LEDs. If you use a 6V
battery, you will need a current limiting resistor to avoid smoking the LEDs.
If you put two in series, you're depending on the bulk resistance of the LED to
limit current -- usually a bad idea. For a 6V battery, with a 3V LED at 20 mA,
you should go with a 150 ohm 1/4 watt resistor. You can either go to radio
shack for these or, if you have the time, order from mouser.com. You can order
100 ea. of their 660-CF1/4L151J for $0.03 USD ea.

Mouser doesn't have a minimum order size, but while you're there, you might
also want to get your neutron/proton/electron switches there, too.An
inexpensive toggle switch which should work for you is their 108-1MS1T1B1M1QE.
You'll need 3 ea. at $1.90 ea. When you mount them on the cardboard display,
put a small metal panel in front to provide rigidity (a thin piece of aluminum
would work well here).

3) If you want to be Mr. Wizard for your kid (one of the best feelings in the
world), you want it to work reliably. Use a soldering iron and rosin-core wire
solder to do the job. If you don't know how, ask around. You'd be surprised
how many people do.

4) Here's how to wire up your project (view in fixed font or M$ Notepad):

.--------o-------------------o--------------------.
| | Neutrons | Protons | Electrons
| .---o-------. .---o-------. .---o-------.
| | | | | | | | | |
| | | LEDs | | | LEDs | | | LEDs |
| V ~ V~. . . V~ V~ V~. . . V~ V~ V~. . . V~
| -~ -~ -~ -~ -~ -~ -~ -~ -~
| | | | | | | | | |
| | | | | | | | | |
| .-. .-. .-. .-. .-. .-. .-. .-. .-.
+| | | | | | | | | | | | | | | | | | |
6V--- | | | | | | | | | | | | | | | | | |
- '-' '-' '-' '-' '-' '-' '-' '-' '-'
| | | | | | | | | |150 ohms
| '---o-------' '---o-------' '---o-------'
| | | |
| o o o
| '\ SW1 '\ SW2 '\ SW3
| \ \ \
| o \ o \ o \
| | | |
| | | |
'--------o-------------------o--------------------'
created by Andy´s ASCII-Circuit v1.24.140803 Beta www.tech-chat.de

You'll find that the LEDs are polarized -- they only light up one way. Usually
one side of the LED has a flat to indicate the cathode, and one lead is longer
than the other. Test on one (with a series resistor) before you wire 'em all
up to find out what works, and then wire them all the same way.

You should try to find 20 or 22 gauge solid insulated wire to do the wiring in
the back of the cardboard. Depending on the size of your project, you may need
50' or 100' of wire. Keep the wires tidy and close together. After you've got
the whole thing working, use spots of hot melt glue to hold the wires in place.
Put another piece of cardboard in back of the first to protect the wiring
during shipping to and from class.

If you have any other questions, feel free to email.

Good luck. This is one of the best parts of being a dad. Enjoy the moment,
and let her work some things out for herself (be sure to supervise if she's
using the soldering iron!)

Chris

 

[Rich Grise]

On Sun, 24 Oct 2004 21:18:06 -0700, Tom Seim wrote:

Rich Grise <rich@example.net> wrote in message news:<pan.2004.10.23.23.40.42.645372@example.net>...
On Sat, 23 Oct 2004 15:47:22 -0700, Tom Seim wrote:

Think Kerry is going to win? Well you can get great odds at

http://www.intrade.com/

$40 will buy you a contract that yields $100 on a Kerry victory. This is
down from $46 just a week ago.

So, how many people will get paid before they go broke?

Cheers!
Rich

Everybody. The Kerry contracts are balanced by the Bush contracts. If
Kerry wins, Kerry contract holders are paid by Bush contract holders,
and visa-versa.

Right, and what happens when the Bush people run out of money?
Or is it just like a football bet, where you pays your money, you
takes your chances?

and they're paying 10 for 4?

Where do I sign up!

Thanks,
Rich

 

[xray]

On Mon, 25 Oct 2004 01:56:30 -0400, Spehro Pefhany
<speffSNIP@interlogDOTyou.knowwhat> wrote:

It takes little
time to pick up the skill and it's a good one to have. Try
asking the counter help at RS to demonstrate soldering a
couple of wires together. They likely have someone there
who can do that for you.

Spehro,

All great comments, and a relief from the off-topic threads (wish I had
your restraint), but this notion about help with soldering from Radio
Shack people might be a bit optimistic.

RS is ok, but in my local one, I'd be surprised if any of the people
have ever soldered anything.

 

[ChrisGibboGibson]

(kell) wrote:

There are ways around having a long delay at "zero" rpm.

All that needs to be done to set an upper limit to the retard is to
put an upper limit on the voltage that C2 can charge to. Putting a
zener across the cap maybe.

You're circuit still works the wrong way round. You get increasing advance with
reducing revs. Exactly what you don't want.

Gibbo

 

[Spehro Pefhany]

On Mon, 25 Oct 2004 06:30:33 GMT, the renowned xray
<notreally@hotmail.invalid> wrote:

On Mon, 25 Oct 2004 01:56:30 -0400, Spehro Pefhany
speffSNIP@interlogDOTyou.knowwhat> wrote:

It takes little
time to pick up the skill and it's a good one to have. Try
asking the counter help at RS to demonstrate soldering a
couple of wires together. They likely have someone there
who can do that for you.

Spehro,

All great comments, and a relief from the off-topic threads (wish I had
your restraint), but this notion about help with soldering from Radio
Shack people might be a bit optimistic.

RS is ok, but in my local one, I'd be surprised if any of the people
have ever soldered anything.

It probably depends on the store. I've actually seen them soldering
things on the counter, in my local RS, once (to make up a patch cable
or something). It's worth asking anyhow. ;-)

I just looked at a couple of sites that claim to tell people how to
solder, and they offer silly (clean the wire with acetone) or outdated
and thus harmful advice (like filing the tip of the soldering iron
first!).


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
speff@interlog.com Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com

 

[Kevin Aylward]

Tim Wescott wrote:

Dbowey wrote:

RE:

Does anybody knows a RLC model for telephone line?
I need to simulate a SLIC in a real environment so need spice model
for telephone line.


What gauge? 22, 24. 26? Mixed gauge? Is any bridge-tap permitted?

A HREF="http://www.wilcominc.com/testcat.htm">Wilcom Inc. - Test
Equipment Catalog</A

You may want to look at the T-240.

Don

That gives you a physical model, but how do you connect the darn thing
to a SPICE simulation?

Easy. Spice has direct support for transmission lines.

I do not think a real telephone line is going to be amenable to
simulation with a simple RLC. It's going to act like a transmission
line, with a characteristic impedance somewhere centered around 100
ohms but varying widely from one to the next, a widely varying
reflection coefficient, a great deal of loss, also varying, and with
a length that can be anywhere from a few feet to a few miles.

Spice has a real T line that has RLC parameters.

In
addition you'll have some bonus signals injected from neighboring
lines, free of charge.

This is a bit more trickey but it can be modelled.

Kevin Aylward
salesEXTRACT@anasoft.co.uk
http://www.anasoft.co.uk
SuperSpice, a very affordable Mixed-Mode
Windows Simulator with Schematic Capture,
Waveform Display, FFT's and Filter Design.

 

[Allan Herriman]

On Sun, 24 Oct 2004 20:08:43 -0700, Tim Wescott
<tim@wescottnospamdesign.com> wrote:

Dbowey wrote:

RE:

Does anybody knows a RLC model for telephone line?
I need to simulate a SLIC in a real environment so need spice model
for telephone line.


What gauge? 22, 24. 26? Mixed gauge? Is any bridge-tap permitted?

A HREF="http://www.wilcominc.com/testcat.htm">Wilcom Inc. - Test Equipment
Catalog</A

You may want to look at the T-240.

Don

That gives you a physical model, but how do you connect the darn thing
to a SPICE simulation?

I do not think a real telephone line is going to be amenable to
simulation with a simple RLC.

That depends on how you define 'simple'.

Please refer to these old s.e.d. threads:
http://groups.google.com/groups?threadm=37c80610.3699565%40newshost.fujitsu.com.au
http://groups.google.com/groups?threadm=d98nh01h4idbr7b6olksre8bo3rngj1mbt%404ax.com
http://groups.google.com/groups?threadm=38563cf5.18091369%40newshost.fujitsu.com.au

Regards,
Allan

 

[Robert Baer]

Tim Wescott wrote:

Dbowey wrote:

RE:

Does anybody knows a RLC model for telephone line?
I need to simulate a SLIC in a real environment so need spice model
for telephone line.


What gauge? 22, 24. 26? Mixed gauge? Is any bridge-tap permitted?

A HREF="http://www.wilcominc.com/testcat.htm">Wilcom Inc. - Test Equipment
Catalog</A

You may want to look at the T-240.

Don

That gives you a physical model, but how do you connect the darn thing
to a SPICE simulation?

I do not think a real telephone line is going to be amenable to
simulation with a simple RLC. It's going to act like a transmission
line, with a characteristic impedance somewhere centered around 100 ohms
but varying widely from one to the next, a widely varying reflection
coefficient, a great deal of loss, also varying, and with a length that
can be anywhere from a few feet to a few miles. In addition you'll have
some bonus signals injected from neighboring lines, free of charge.

Aside from that it should be a snap to simulate.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

I believe that WeCo specified 500 ohms, and that all modem and phone
balun transformers are speced at 600 ohms.
For short length simulation (even in real life), a simple RLC will do.
When at Fairchild, we made a tester for a tone generator chip for a
MaBell supplier, and had to use an RLC network to simulate the line, for
proper testing.
The inductance was "substantial" (in the henry region), and ordinary
on/off switching of an automatic tester would have required many seconds
for stabilization of inductor current - thereby severely restricting
test thruput to unacceptable levels.
Unfortunately, that was a loooooong time ago, and i do not remember
the inductor value.
However, the phone line is 48-50V open circuit, and one can readily
measure the short circuit current, to give the total series resistance.
Look at loop simulator circuits as provided in part 68 of the FCC
Rules and Regulations.
**
From some rather old books i have:
1) Page 29 of The Master Handbook of Telephones (Tab Books 1981)
Tip to R2 to inductor (L=>10H, Rl) to Vbat to Ring in parallel with
Tip to C1 to R1 to Ring.
Vbat min=42.5V, max=52.5V; R2+Rl variable from 400 ohms to 1740 ohms.
No notes seen for R1 or C1.
2) Page 39 of You & Your Telephone (Sams 1980)
Shows network circuit diagram GIF available on request). [[C1 is
about 2uF]]
3) Other books i have give no schematics or equivalents.
**
If you look at old telephone poles, note the wire spacing; it is a
transmission line!
Getting dimensions (wire spacing and wire size) will allow one to
derive the impedance.