Driver to drive?

Tim Williams wrote:

On Apr 27, 1:44 pm, Eeyore <rabbitsfriendsandrelati...@hotmail.com
wrote:
Displacement Factor is the fudamental only.

Never heard that term. Can you explain ?

http://en.wikipedia.org/wiki/Power_factor#Non-sinusoidal_components

It's mentioned in a paragraph or two.
A search couldn't find it.

Graham
 
On Fri, 24 Apr 2009 11:55:47 -0700, James Sweet
<jamessweet1@trashmail.net> wrote:

Andrew Gabriel wrote:
In article <6pKdnW_chZqtYmzUnZ2dnUVZ_j1i4p2d@supernews.com>,
Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> writes:
Andrew Gabriel wrote:
In article <fjlIl.34167$fe2.29061@newsfe06.ams2>,
"ian field" <gangprobing.alien@ntlworld.com> writes:
In countries with different mains voltage, the ratio may need
adjusting, as filament lamp efficiency varies with the design
voltage. (The most efficient voltage to design a 100W lamp is
about 55V, given a reasonable life requirement, and as you move
the design voltage away from 55V in either direction, the lamp
efficiency drops.)

Interesting. I can see it dropping due to conduction losses when the
voltage gets too low (so that the wire gets too fat) but what's the
mechanism for the drop-off at high voltages?

Designing a full range of filament lamps to operate over a
wide range of voltages is a challenge rather like trying to
solve a set of simultaneous equations when there aren't
enough variables, so you end up with compromises, such as
lower efficiency.

To make a 240V filament, you need a very long thin wire.
It has far too much surface area to get to the 2700K operating
temperature without radiating 100W away at a lower temperature.
The way 240V filament lamps are made to work is to double
coil the filament, so that much of the filament is radiating
heat back onto itself, and the effective surface area for
radiating heat away from the filament is significantly
less than the filament's real surface area. This isn't as
effective as using an optimum thickness filament in the first
place, i.e. you have just the right surface area to radiate
100W when it's reached 2700K, and you still have a larger
surface area for filament evaporation and thinning.

And yes, you're right about heat loss by conduction down the
lead-in wires becoming increasingly significant at low
voltages/high currents. With longer fragile filaments, the loss
from the ends is proportionally less, but you may also require
filament supports, which are additional routes to lose heat,
and you lose more by convection to the gas-fill.



Most 120V tungsten lamps use a coiled coil filament as well, as do some
lower voltage lamps.

A major issue with long thin filaments is convective loss to the fill
gas. If you eliminate the fill gas and use a vacuum instead to solve
this problem, you greatly increase the evaporation rate of the tungsten;
out of the frying pan and into the fire.
And thus the quartz halogen lamps.
.
 
Speaking of failing TVs... :cool:
Rule 1 (or is it 4...?) of news groups: do not hijack a thread.

If you want to ask another question, please start your own thread.

Cheers,
--
John English
 
Charlie E. <edmondson@ieee.org> wrote in
news:hkccv4te77bdf8g96v7o9oniqti2hoh2i7@4ax.com:

On Sun, 26 Apr 2009 08:36:58 -0700, John E. <incognito@xbjcd.com
wrote:

It is mostly the TV programs that fail.

Very funny. I agree: My TV won't survive another episode of "Lost".

But that's a discussion for another time...

Speaking of failing TVs... :cool:

My old Zenith 25" TV has been doing the oddest thing. The menus are
going crazy, like someone was randomly hitting the menu button on my
remote. The menus pop up, start changing different values, go here
and there throughout the menu tree. It drives me crazy to try and
watch it! My wife doesn't mind, though... ;-)

Any ideas what could be causing it? At first, I thought it might be a
remote problem, or even a remote interaction problem, but it doesn't
look like it. I even to out the batteries to all the remotes, and
covered the IR receiver window, but it still kept going crazy. My
only thought is some sort of fault on the logic board, or something.

Charlie
probably bad electrolytic caps.
perhaps one or more of your LV supplies is getting out of spec,and
affecting the logic ICs.

--
Jim Yanik
jyanik
at
kua.net
 
On Apr 27, 9:43 pm, Eeyore <rabbitsfriendsandrelati...@hotmail.com>
wrote:
It's mentioned in a paragraph or two.

A search couldn't find it.
Second paragraph from link,

"In circuits having only sinusoidal currents and voltages, the power
factor effect arises only from the difference in phase between the
current and voltage. This is narrowly known as "displacement power
factor". The concept can be generalized to a total, distortion, or
true power factor where the apparent power includes all harmonic
components."

Tim
 
Tim Williams wrote:

Eeyore <rabbitsfriendsandrelati...@hotmail.com> wrote:

It's mentioned in a paragraph or two.

A search couldn't find it.

Second paragraph from link,

"In circuits having only sinusoidal currents and voltages, the power
factor effect arises only from the difference in phase between the
current and voltage. This is narrowly known as "displacement power
factor". The concept can be generalized to a total, distortion, or
true power factor where the apparent power includes all harmonic
components."
You said initially "displacement factor" without the power hence the
absence of hits.

It would be good if phase only related PFC ( motors etc ) could be
better distinguished from harmonics. The average bod gets confused about
the whys and wherefores of the two.

Graham
 
On Sat, 25 Apr 2009 05:32:08 -0700, Jim Thompson
<To-Email-Use-The-Envelope-Icon@My-Web-Site.com> wrote:

On Sat, 25 Apr 2009 01:01:49 -0400, T <kd1s.nospam@cox.nospam.net
wrote:

In article <95nvu4l035ecbfca5afbua1277fsuqmoqj@4ax.com>,
krw@att.bizzzzzzzzzzz says...

On Wed, 22 Apr 2009 18:16:47 -0700, Jim Thompson
To-Email-Use-The-Envelope-Icon@My-Web-Site.com> wrote:

On Wed, 22 Apr 2009 18:11:07 -0500, krw <krw@att.bizzzzzzzzzzz> wrote:

On Wed, 22 Apr 2009 14:53:26 -0700, John Larkin
jjlarkin@highNOTlandTHIStechnologyPART.com> wrote:

On Tue, 21 Apr 2009 23:23:05 -0500, krw <krw@att.bizzzzzzzzzzz> wrote:


Another example is the dominant furniture style: IKEA making slow inroads
against the standard velvety sofa http://www.homereserve.com/furn-
style.cfm?item=Sofa&sel=7

Hardly "dominant", but common and comfortable. We have all sorts of
furniture here, too. A lot of the Ikea stuff isn't comfortable.

IKEA certainly isn't dominant. In fact I've never seen it in anyone's
house. Perhaps it's ubiquitous in left lefty land but not the rest of
the country.

We did our offices mostly in Ikea. This "computer workstation" makes a
very nice workbench, except that they have discontinued it.

ftp://jjlarkin.lmi.net/DSC01371.JPG

Looks pretty light. I'm used to 1-1/2" laminated maple tops.

The cabinet to the left is Ikea too. I like their office furniture
better than their home stuff, but it's all OK, and cheap.

We bought some Ikea stuff for the cabin in Truckee. We had to haul it
from Sacramanto, because there's not a single Ikea in Nevada.

Their swedish meatballs are pretty good.

Ikea meatballs taste like sawdust. ;-)

This is a big country with a lot of variety. And there's nothing wrong
with tradition.

I prefer Ohio Amish built Mission style furniture, in Cherry.

http://www.greenacresfurniture.com/catalog/content/productcollection/?collection=118

...and it'll last longer than particle board with a picture of wood on
it.


Wood? All the way through?

Cherry. All the way through. The Amish still build real furniture.

Here is our dining room:

http://www.greenacresfurniture.com/catalog/content/productcollection/?collection=117

We don't have the corner cupboard or the buffet, but have six chairs.
The table has four leaves stored in the center section and opens to
10'. It's heavy stuff.

A _real_ table (granite)...

http://www.analog-innovations.com/FamilyPixs/dsc00006.jpg

All of the counters in our house (five in the kitchen, two in the
great room, and three full bathrooms) with the exception of tha
laundry are granite. I'd rather have wood for some of them but my
wife doesn't like butcher block counters.

Enjoy the radon exposure. Apparently some granite is pretty radioactive.


What a rock pile of nonsense ;-)

...Jim Thompson
Actually true. Some granite has a uranite component. Also some
feldspar (a common component in granite) is ususally mildly
radioactive. Also, radioactive components in granite may not produce
any radon.
.
 
On Thu, 30 Apr 2009 18:55:51 -0700,
"JosephKK"<quiettechblue@yahoo.com> wrote:

On Sat, 25 Apr 2009 05:32:08 -0700, Jim Thompson
To-Email-Use-The-Envelope-Icon@My-Web-Site.com> wrote:

On Sat, 25 Apr 2009 01:01:49 -0400, T <kd1s.nospam@cox.nospam.net
wrote:

In article <95nvu4l035ecbfca5afbua1277fsuqmoqj@4ax.com>,
krw@att.bizzzzzzzzzzz says...

On Wed, 22 Apr 2009 18:16:47 -0700, Jim Thompson
To-Email-Use-The-Envelope-Icon@My-Web-Site.com> wrote:

[snip]

A _real_ table (granite)...

http://www.analog-innovations.com/FamilyPixs/dsc00006.jpg

All of the counters in our house (five in the kitchen, two in the
great room, and three full bathrooms) with the exception of tha
laundry are granite. I'd rather have wood for some of them but my
wife doesn't like butcher block counters.

Enjoy the radon exposure. Apparently some granite is pretty radioactive.


What a rock pile of nonsense ;-)

...Jim Thompson

Actually true. Some granite has a uranite component. Also some
feldspar (a common component in granite) is ususally mildly
radioactive. Also, radioactive components in granite may not produce
any radon.
.
The Radon scare, exceeded only in hype by global warming. I made some
money from the Radon scare... maybe I can conjure a way to use global
warming to my advantage ;-)

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |

I love to cook with wine Sometimes I even put it in the food
 
Jim Thompson wrote:
The Radon scare, exceeded only in hype by global warming. I made some
money from the Radon scare... maybe I can conjure a way to use global
warming to my advantage ;-)

Sell a Global Warming Alarm. It doesn't have to really do anything,
except run down lots of batteries.


--
You can't have a sense of humor, if you have no sense!
 
On Fri, 01 May 2009 13:17:48 -0400, "Michael A. Terrell"
<mike.terrell@earthlink.net> wrote:

Jim Thompson wrote:

The Radon scare, exceeded only in hype by global warming. I made some
money from the Radon scare... maybe I can conjure a way to use global
warming to my advantage ;-)


Sell a Global Warming Alarm. It doesn't have to really do anything,
except run down lots of batteries.
I could make a CO2 monitor, just like I made a Radon monitor...
although it might be easier to make a hot air monitor ;-)

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |

I love to cook with wine Sometimes I even put it in the food
 
Jim Thompson wrote:
On Fri, 01 May 2009 13:17:48 -0400, "Michael A. Terrell"
mike.terrell@earthlink.net> wrote:


Jim Thompson wrote:

The Radon scare, exceeded only in hype by global warming. I made some
money from the Radon scare... maybe I can conjure a way to use global
warming to my advantage ;-)


Sell a Global Warming Alarm. It doesn't have to really do anything,
except run down lots of batteries.

I could make a CO2 monitor, just like I made a Radon monitor...
although it might be easier to make a hot air monitor ;-)

Don't turn it towards Europe without a 'Peltier Front End Attenuator'
or it will self distruct.

--
You can't have a sense of humor, if you have no sense!
 
On Fri, 01 May 2009 13:43:01 -0400, "Michael A. Terrell"
<mike.terrell@earthlink.net> wrote:

Jim Thompson wrote:

On Fri, 01 May 2009 13:17:48 -0400, "Michael A. Terrell"
mike.terrell@earthlink.net> wrote:


Jim Thompson wrote:

The Radon scare, exceeded only in hype by global warming. I made some
money from the Radon scare... maybe I can conjure a way to use global
warming to my advantage ;-)


Sell a Global Warming Alarm. It doesn't have to really do anything,
except run down lots of batteries.

I could make a CO2 monitor, just like I made a Radon monitor...
although it might be easier to make a hot air monitor ;-)


Don't turn it towards Europe without a 'Peltier Front End Attenuator'
or it will self distruct.
Sno-o-o-o-ort!

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |

I love to cook with wine Sometimes I even put it in the food
 
On Fri, 18 Apr 2008 09:20:59 -0700, Jim Thompson
<To-Email-Use-The-Envelope-Icon@My-Web-Site.com> wrote:

On Fri, 18 Apr 2008 08:43:00 -0700, Jim Thompson
To-Email-Use-The-Envelope-Icon@My-Web-Site.com> wrote:

On Fri, 18 Apr 2008 10:59:07 -0400, Fred Bloggs <nospam@nospam.com
wrote:



krw wrote:


You keep telling the same lies, Phyllis.



You're a sorry-assed piece of garbage, you don't know anything about
electronics and you're too stupid to learn, so why do you post to SED?


I really want to express my sincere thanks to you "gentlemen" for
assisting me in creating a filter (in Agent) that stops this crap dead
in its tracks ;-)

Other Agent users: Contact me directly for the particulars.

==============================================================

I wasn't terribly clear... it's a filter to kill-off the
master-baiters.

If it is used in conjunction with nfilter it becomes DEADLY... ANYONE
who replies to Slowman, or he-with-too-many-nyms, will not be seen,
EVER !!

I am so-o-o-o-o happy !!

Now back to my panic back-up... I have a suddenly noisy hard-drive :-(

...Jim Thompson
Hi Jim,
You found a way to filter out all of those fake watch and shoe
posts? I had not been here for a long time but the amount of pure
non-electronics junk has just amazed me.

Guess I need to start adding some filters, show, watch, fake....
 
On Fri, 01 May 2009 21:59:20 -0400, Bob Thomas <bobtms@hotmailx.com>
wrote:

On Fri, 18 Apr 2008 09:20:59 -0700, Jim Thompson
To-Email-Use-The-Envelope-Icon@My-Web-Site.com> wrote:

On Fri, 18 Apr 2008 08:43:00 -0700, Jim Thompson
To-Email-Use-The-Envelope-Icon@My-Web-Site.com> wrote:

On Fri, 18 Apr 2008 10:59:07 -0400, Fred Bloggs <nospam@nospam.com
wrote:



krw wrote:


You keep telling the same lies, Phyllis.



You're a sorry-assed piece of garbage, you don't know anything about
electronics and you're too stupid to learn, so why do you post to SED?


I really want to express my sincere thanks to you "gentlemen" for
assisting me in creating a filter (in Agent) that stops this crap dead
in its tracks ;-)

Other Agent users: Contact me directly for the particulars.

==============================================================

I wasn't terribly clear... it's a filter to kill-off the
master-baiters.

If it is used in conjunction with nfilter it becomes DEADLY... ANYONE
who replies to Slowman, or he-with-too-many-nyms, will not be seen,
EVER !!

I am so-o-o-o-o happy !!

Now back to my panic back-up... I have a suddenly noisy hard-drive :-(

...Jim Thompson

Hi Jim,
You found a way to filter out all of those fake watch and shoe
posts? I had not been here for a long time but the amount of pure
non-electronics junk has just amazed me.

Guess I need to start adding some filters, show, watch, fake....
Bob, I'll E-mail you privately (tomorrow... relaxation time right now
;-)

I can do most everything with ONLY Agent filters, EXCEPT for the jerks
who feed certain nameless/worthless trolls, but I have a manual
solution for them, just need to concoct the right script, and I'll be
bullet proof.

I'll send my filter set sometime tomorrow.

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |

I love to cook with wine Sometimes I even put it in the food
 
On Sun, 03 May 2009 21:43:15 -0700, Dave wrote:

So the rabbit swims an arc. The agent is running a counterclockwise circular
curve while the rabbit is swimming a counterclockwise...outward spiral.

No. The rabbit wants to swim in a straight line. It is the shortest
distance from where he is to a point on the shore. If he swims in an
arc, it will take longer than on a line, meaning that the agent has
more time to reach him.
If the rabbit swims in a straight line from the centre, the agent can beat
him to the shore. So he must get closer to the shore while remaining
diametrically opposite the agent.

So long as the rabbit is less than r/4 from the centre, he can maintain
diametric opposition. If the agent runs clockwise, the rabbit swims
anti-clockwise and vice-versa. The rabbit moves at 1/4 of the speed,
but is at less than 1/4 the radius, so his maximum angular speed is
higher than the agent's. He only needs to match the angular speed,
so whatever speed is left over can be used for outward motion.

Once he reaches r/4 from the center, the rabbit can maintain diametric
opposition, but not while moving outward. But at this point, he is only
3r/4 from the closest point on the shore, while the agent is pi*r from
that point. So he can head in a straight line to the shore and get there
before the agent does.
 
On 2009-05-03, Joerg <notthisjoergsch@removethispacbell.net> wrote:
RFI-EMI-GUY wrote:

In my house attic, I have several 4 inch white PVC vent stacks which are
simply white PVC drain pipe extending from the wall headers through the
attic and the roof. On the roof, these are covered with lead flashing to
prevent water from getting inside the house. I have been doing a lot of
work in the attic, and have noticed that these pipes "glow" quite
noticeably as a result of the sunlight outside. As this often happens
when the sun is at the horizon and thus at an angle below which direct
coupling into the pipe would be possible, I am very curious as to the
reason that the visible infrared portion is so much more visible than
white light spectrum. Has anyone else noticed this? What is going on?


White PVC sticking out the roof? 4"? Wow. White PVC usually becomes
rotten from UV pretty quickly. If it isn't painted it begins to turn
brown within 2-3 years in our area. After some more years you can
sometimes crumble it by hand.
if it's loaded with TiO it'll last several decades exposed.
 
On Mon, 04 May 2009 00:23:13 -0700, Robert Baer
<robertbaer@localnet.com> wrote:

flipper wrote:
On Mon, 04 May 2009 05:53:12 +0100, Eeyore
rabbitsfriendsandrelations@hotmail.com> wrote:



Archimedes' Lever wrote:


Jim Thompson wrote:

Success!

See...

http://analog-innovations.com/SED/TROLLFEEDER.jpg

Had to resort to NewsProxy until Agent gets a "References:" filter.

Will now just add, to Agent...

999 Delete: Subject:TROLLFEEDER

Then I won't even see the "TROLLFEEDER" tag.

Someone tell NymNuts, it _is_ universal, presently covering NymNuts,
Eeyore and Slowman follow-ups.

So, as far as I'm concerned, these "folks" don't exist anymore ;-)

...Jim Thompson

JimBob Brainlees Fart's head finally exploded.

It has been quite enjoyable watching him sink deeper and deeper into
his stupidity based seclusion desires.

Have fun being a net recluse. That has to be one of the most retarded
acts ever performed.

I have to agree with you.

The USA claims to be so in favour of 'free speech' yet it's the Americans
here who don't want to hear views that are contrary to their own.

Very odd.


It's called "freedom of speech," not "mandatory listening," and
there's nothing in 'free speech' that requires anyone pay attention.



Graham
PAY attention?
You think i am rich or something?
Hey, I said you were *not* required to 'pay'.

I suspected someone would make a 'pay' joke, I just wasn't sure what
form it would take.
 
riverman wrote:
On May 3, 10:17 am, Sylvia Else <syl...@not.at.this.address> wrote:
Mark-T wrote:
DId anyone here see the problem presented in
the Science section of NY Times last week?
Quite startling, to see something so sophisticated
in a 'general readership' publication.
Is it solvable without a calculus of variations approach?
--
Mark
Yes.

Spoiler below 13

0

1

2

3

4

5

6

7

9

10

11

12

13

Since the agent can run four times as fast as the rabbit can swim, no
matter what the agent does, the rabbit can swim away from the centre,
and keep the agent on the far side as long as the rabbit is no more than
1/4 of the radius from the centre. So the rabbit can reach a point 3/4
of a radius from the edge while the agent is still on the opposite side.


Only if the agent stands still until the last possible moment. I think
the agent will move continuously, and as soon as the rabbit starts
moving in any direction, the agent will move toward the point that is
the closest to the rabbit at that moment. Let's call the agent 'Xeno'.
No - until the rabbit is 1/4 of the radius away from the centre, he can
swim fast enough, in a suitable direction, to keep the agent exactly
opposite. So it doesn't matter if the agent moves.

Sylvia.
 
On a sunny day (Sun, 3 May 2009 21:21:54 -0700 (PDT)) it happened mj
<elucify@gmail.com> wrote in
<dda2ac06-f0ff-4535-9de3-68576e4a8651@o27g2000vbd.googlegroups.com>:

I'm looking for ideas on how to make an LED flash so brightly at a low
duty cycle that it's reasonably bright--maybe even close to what it
would be if it were on DC.

I'm building a project where I need to flash white LEDs very brightly
30-50 times a second at about a 0.4% duty cycle. (I'm strobing a
spinning disk, and want to freeze images near the LED--too high a duty
cycle, and the image blurs.) 0.4% is not much time for an LED to be
on. I've heard that you can drive LEDs to up to 10x their normal
forward current without damage (though I guess lifetime is shortened)
if you keep duty cycle to <= 1%.

I have exactly that here, made it for strobe tests.
White LED too, uses an 8 pin PIC, and 2 transistors to get some high current.
Want the asm source? Could perhaps still find it.
 
Sylvia Else <sylvia@not.at.this.address> writes:

riverman wrote:
On May 3, 10:17 am, Sylvia Else <syl...@not.at.this.address> wrote:
Mark-T wrote:
DId anyone here see the problem presented in
the Science section of NY Times last week?
Quite startling, to see something so sophisticated
in a 'general readership' publication.
Is it solvable without a calculus of variations approach?
--
Mark
Yes.

Spoiler below 13

0

1

2

3

4

5

6

7

9

10

11

12

13

Since the agent can run four times as fast as the rabbit can swim, no
matter what the agent does, the rabbit can swim away from the centre,
and keep the agent on the far side as long as the rabbit is no more than
1/4 of the radius from the centre. So the rabbit can reach a point 3/4
of a radius from the edge while the agent is still on the opposite side.


Only if the agent stands still until the last possible moment. I think
the agent will move continuously, and as soon as the rabbit starts
moving in any direction, the agent will move toward the point that is
the closest to the rabbit at that moment. Let's call the agent 'Xeno'.

No - until the rabbit is 1/4 of the radius away from the centre, he
can swim fast enough, in a suitable direction, to keep the agent
exactly opposite. So it doesn't matter if the agent moves.
Which shows, I think (to return to the very original question about
whether this needs horrible maths to solve) that there is a simple proof
that pretty-well anyone can follow that shows the rabbit can escape in
the specific case (it goes to where it can just swim faster than the
agent, swims round in a circle until it gets to 180 degrees away from
the agent, and can then make it to the shore faster than the agent can
run round), but that the optimum strategy, and hence the answer to the
unasked question about which size of ponds or relative speeds allow the
rabbit to escape do require the horrid maths.
--
Online waterways route planner: http://canalplan.org.uk
development version: http://canalplan.eu
 

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