"BIOS problem" solved

Gene E. Bloch wrote:
On Fri, 07 Nov 2014 00:34:31 -0500, Paul wrote:

Gene E. Bloch wrote:

What does all that have to do with my youthful "understanding" of wire?
Well, my young friend, this is wire with blue
chewing gum inside. Try a bite...

http://www.satacables.com/assets/images/IMG_188353.jpg

Pauk

To tell the truth, I don't think any of the things you've mentioned or
linked to are a problem for standard lampcord at 60Hz (though it was
called 60 cycles back then).


The code words here, suggest lines over 240km long might be
modeled as transmission lines.

http://eee.guc.edu.eg/Courses/Electr...on%20Lines.pdf

And the article here, suggests 775 miles as a good length at
which to change electrical equivalent model.

http://www.allaboutcircuits.com/vol_2/chpt_14/5.html

"For a 60 Hz AC power system, power lines would have to
exceed 775 miles in length before the effects of
propagation time became significant."

And for various reasons, we don't build extremely long single
hops for power transmission. So maybe switching modeling
schemes, isn't a big issue.

http://en.wikipedia.org/wiki/Geomagn...nduced_current

*******

At the frequency of interest (60Hz), the lamp cord is "electrically
short", so a lumped model is sufficient to describe the behavior.

If the electrical connection between two SATA devices was
short enough, you might not need any special treatment
of the signals. That distance would likely be a fraction
of an inch, and so the distinction isn't an important one.
For all practical SATA connection instances, you need transmission
lines of appropriate design. (Copper tracks on a PCB can be
used as transmission lines. Known as stripline or microstrip.)

Paul

Brian Gregory wrote:


I'm sure SATA does have terminators, it's just that they're built in to
the devices at the ends of the cable, and there are no devices connected
anywhere in the middle of the cable.

My understanding is that PATA does too but that they're not terminated
very precisely, so that whether you have one drive or two it still works
"well enough".

The IDE ribbon cable bus is source terminated (series damped).

This is a Microsoft Word doc.

See section D.2.2.4 "Source-terminated bus" on page 198.

http://t13.org/Documents/UploadedDoc...0511%20GSR.DOC

Paul

"Paul" wrote in message
...
Gene E. Bloch wrote:
On Fri, 07 Nov 2014 00:34:31 -0500, Paul wrote:

Gene E. Bloch wrote:

What does all that have to do with my youthful "understanding" of wire?
Well, my young friend, this is wire with blue
chewing gum inside. Try a bite...

http://www.satacables.com/assets/images/IMG_188353.jpg

Pauk

To tell the truth, I don't think any of the things you've mentioned or
linked to are a problem for standard lampcord at 60Hz (though it was
called 60 cycles back then).


The code words here, suggest lines over 240km long might be
modeled as transmission lines.

http://eee.guc.edu.eg/Courses/Electr...on%20Lines.pdf

And the article here, suggests 775 miles as a good length at
which to change electrical equivalent model.

http://www.allaboutcircuits.com/vol_2/chpt_14/5.html

"For a 60 Hz AC power system, power lines would have to
exceed 775 miles in length before the effects of
propagation time became significant."

And for various reasons, we don't build extremely long single
hops for power transmission. So maybe switching modeling
schemes, isn't a big issue.

http://en.wikipedia.org/wiki/Geomagn...nduced_current

*******

At the frequency of interest (60Hz), the lamp cord is "electrically
short", so a lumped model is sufficient to describe the behavior.

If the electrical connection between two SATA devices was short enough,
you might not need any special treatment of the signals. That distance
would likely be a fraction of an inch,

No it is not with the effect of a kink.

and so the distinction isn't an important one.

There is a reason for the limit to the length of SATA data cables.

For all practical SATA connection instances, you need transmission
lines of appropriate design. (Copper tracks on a PCB can be
used as transmission lines. Known as stripline or microstrip.)

That is a separate matter entirely to the effect of a kink.

In message , Gene E. Bloch
writes:
On Fri, 7 Nov 2014 13:19:00 +0100, Linea Recta wrote:
[]
I always thought that uploading to a friend in Switserland took more time
than the other way round because it had to go up the mountains!

You also have to deal with a redshift due to relativistic effects. It
wild be a blueshift going downhill.

Or is it the other way around?

Doesn't it depend whether you're going with the earth's rotation or
against it?
--
J. P. Gilliver. UMRA: 1960/1985 MB++G()AL-IS-Ch++(p)Ar@T+H+Sh0!:`)DNAf

# 10^-12 boos = 1 picoboo # 2*10^3 mockingbirds = 2 kilo mockingbird
# 10^21 piccolos = 1 gigolo # 10^12 microphones = 1 megaphone
# 10**9 questions = 1 gigawhat

In message , Brian
Gregory writes:
On 06/11/2014 19:04, Rod Speed wrote:
Paul wrote
[]
"Never bend a SATA data cable tighter than a 30 mm (1.18 in) radius.
Never crease a SATA data cable."

That isnt for the reason you were talking about.

PLEASE EXPLAIN.

He's probably claiming that those instructions are to do with damage
rather than impedance changing.

(Had he suggested that they might be _more_ to do with damage than
impedance changing, he might have had something.)
[]
--
J. P. Gilliver. UMRA: 1960/1985 MB++G()AL-IS-Ch++(p)Ar@T+H+Sh0!:`)DNAf

# 10^-12 boos = 1 picoboo # 2*10^3 mockingbirds = 2 kilo mockingbird
# 10^21 piccolos = 1 gigolo # 10^12 microphones = 1 megaphone
# 10**9 questions = 1 gigawhat

"J. P. Gilliver (John)" wrote in message
...
In message , Brian Gregory
writes:
On 06/11/2014 19:04, Rod Speed wrote:
Paul wrote
[]
"Never bend a SATA data cable tighter than a 30 mm (1.18 in) radius.
Never crease a SATA data cable."

That isnt for the reason you were talking about.

PLEASE EXPLAIN.

He's probably claiming that those instructions are to do with damage
rather than impedance changing.

Corse they are, because a radius of 25mm won't
have any significant effect on the impedance.

(Had he suggested that they might be _more_ to do with damage than
impedance changing, he might have had something.)

I have everything anyway.

On Sat, 08 Nov 2014 18:44:48 -0500, Paul wrote:

Gene E. Bloch wrote:
On Fri, 07 Nov 2014 00:34:31 -0500, Paul wrote:

Gene E. Bloch wrote:

What does all that have to do with my youthful "understanding" of wire?
Well, my young friend, this is wire with blue
chewing gum inside. Try a bite...

http://www.satacables.com/assets/images/IMG_188353.jpg

Pauk

To tell the truth, I don't think any of the things you've mentioned or
linked to are a problem for standard lampcord at 60Hz (though it was
called 60 cycles back then).


The code words here, suggest lines over 240km long might be
modeled as transmission lines.

http://eee.guc.edu.eg/Courses/Electr...on%20Lines.pdf

And the article here, suggests 775 miles as a good length at
which to change electrical equivalent model.

http://www.allaboutcircuits.com/vol_2/chpt_14/5.html

"For a 60 Hz AC power system, power lines would have to
exceed 775 miles in length before the effects of
propagation time became significant."

And for various reasons, we don't build extremely long single
hops for power transmission. So maybe switching modeling
schemes, isn't a big issue.

http://en.wikipedia.org/wiki/Geomagn...nduced_current

*******

At the frequency of interest (60Hz), the lamp cord is "electrically
short", so a lumped model is sufficient to describe the behavior.

If the electrical connection between two SATA devices was
short enough, you might not need any special treatment
of the signals. That distance would likely be a fraction
of an inch, and so the distinction isn't an important one.
For all practical SATA connection instances, you need transmission
lines of appropriate design. (Copper tracks on a PCB can be
used as transmission lines. Known as stripline or microstrip.)

Paul

OK, then there might be a problem with the old suggestion for an
electric car that could go hundreds of miles on electricity, as long as
the extension cord was long enough.

--
Gene E. Bloch (Stumbling Bloch)

On Sun, 9 Nov 2014 10:18:54 +0000, J. P. Gilliver (John) wrote:

In message , Gene E. Bloch
writes:
On Fri, 7 Nov 2014 13:19:00 +0100, Linea Recta wrote:
[]
I always thought that uploading to a friend in Switserland took more time
than the other way round because it had to go up the mountains!

You also have to deal with a redshift due to relativistic effects. It
wild be a blueshift going downhill.

Or is it the other way around?

Doesn't it depend whether you're going with the earth's rotation or
against it?

I guess you have to take both that and the gravitational redshift into
account. Thanks for reminding me - I had totally forgotten that.

As for red vs blue shift, the real problem is that I don't remember
which way it goes as you move up out of the depths of the gravitational
well.

We also need to account for the rotation direction of the water going
out of the drain, IIRC.

Or maybe we (OK, *I*) just need to get a life :-)

--
Gene E. Bloch (Stumbling Bloch)

Gene E. Bloch wrote:


OK, then there might be a problem with the old suggestion for an
electric car that could go hundreds of miles on electricity, as long as
the extension cord was long enough.

We'll just have to try it. Here, let me get my car
out of the garage. I have a 240km cord around here
somewhere...

I did actually build an electric car as a kid. It used
a washing machine motor. The pulleys weren't geared right,
so I couldn't use it regularly. But I did get it to go
about 20 or 30 feet around the side of the house. I can
see me driving that baby to work now. And having the
rubber belt snap halfway through the trip (because it
wasn't geared right). I would have needed another pair of
pulleys to get the ratio into the right range.

Paul

On Mon, 10 Nov 2014 00:16:09 -0500, Paul wrote:

Gene E. Bloch wrote:


OK, then there might be a problem with the old suggestion for an
electric car that could go hundreds of miles on electricity, as long as
the extension cord was long enough.

We'll just have to try it. Here, let me get my car
out of the garage. I have a 240km cord around here
somewhere...

Come on, Paul, one model of the Tesla has a 300 mi (almost 500 km) range
and it doesn't even need an extension cord :-)

After yesterday's posts, I got to thinking about street cars and what I
call trackless trolleys. I realized that the overhead wires really
function just like an extension cord.

Kind of ruins the old joke :-)

Trackless trolleys was the term when I was a kid in Philadelphia for
electric buses that were powered like streetcars (called trolley cars in
Phillie) by overhead wires. I mention that because all of those things
had different names in the different cities I grew up in.

I did actually build an electric car as a kid. It used
a washing machine motor. The pulleys weren't geared right,
so I couldn't use it regularly. But I did get it to go
about 20 or 30 feet around the side of the house. I can
see me driving that baby to work now. And having the
rubber belt snap halfway through the trip (because it
wasn't geared right). I would have needed another pair of
pulleys to get the ratio into the right range.

Paul

That's really impressive, even if it didn't go far. Creative.

--
Gene E. Bloch (Stumbling Bloch)