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Orchid XP v3 wrote:
> Can anybody suggest why this might be? I mean, huge powerful electric
They just are.
I find it interesting that you're focusing on power rather than energy.
How long do you spend boiling water vs how long is the washer running?
--
Atheism is a non-prophet organization.
/\ /\ /\ /
/ \/ \ u e e n / \/ a w a z
>>>>>>mue### [at] nawaz org<<<<<<
anl
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>> Yes, but 4 W!!!! 4 mW should be enough.
>
> Perhaps, depends on what other features the kit has, though.
How about running an LCD panel, transmitting and receiving data from a
base-station 10s of miles away, interpreting incoming data packets, waiting
for key presses? All for 10 mW.
> I know, for example, that the system I have here at my feet has an ATX
> board, which means the "power" switch is solid state rather than a
> physical switch. That means the board is powered all the time (when the
> power supply switch is on at the back of the system).
The main point is that mainboard and PSU makers have no incentive to make a
low power and efficient "off" state. Really, such a small fraction of
people/companies will make a decision based on the efficiency of the off
state it is not worth it at all.
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> Even so... that takes it up to, what, 19 mW? I don't know what the other
> 3,981 W is for...
Heat.
> Convesly, the PC uses *less* power than I was expecting when turned on,
> so...
Is that with or without POV rendering? ;-) Go on then, tell us how much it
would cost to do a 9 month render...
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> Oh... no, not really. I mean, sound vibrations are really, *really* tiny.
> (Think about it; even when the sound is turned up painfully loud, the
> speaker cones move by such a tiny amount you can't even see them move at
> all!)
Huh? Even at normal listening volumes I can see the bass cones move on
mine... Try feeding a 20 Hz sine wave in and watch the cone... These are
only perhaps 6" drivers, nothing spectacular. Mind you, I have never
noticed the tiny 2" cones move on my PC speakers.
> AFAIK, the reason we have 200 W amplifiers and speakers isn't so much
> because it takes that much electricity to move air around, but to reduce
> RF pickup in the speaker wire... (Or rather, to reduce the *signifigance*
> of such pickup.)
Huh? You are saying that they deliberately make speakers less efficient so
that a higher voltage can be used to drive them? I've never heard that
before. Also I have never seen much "serious" hi-fi rated at anything like
200 W for home use. IME 15 W per channel is plenty to fill a medium sized
room very loudly, perhaps if you live in a very large house and like
listening to music very loud you'd want 200 W.
> The mater claims 249.98 V.
Sounds ok to me, the voltage will fluctuate a lot depending on lots of
factors, like how much power people are using around you etc. Try measuring
the voltage at different times of the day...
> Also, 49.97 Hz. (So much for "they keep it to exactly 50 Hz to help all
> those clocks that use it". The frequency waivers all over the place!)
And you think your meter is accurate to +/- 0.03 Hz? It's worth noting that
the national grid in the UK keeps all power stations interconnected so all
generators *must* make power at the same frequency. If everyone in the
country turned on their kettles then the frequency and voltage would
probably drop significantly...
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On Mon, 03 Sep 2007 08:45:39 +0200, scott wrote:
>>> Yes, but 4 W!!!! 4 mW should be enough.
>>
>> Perhaps, depends on what other features the kit has, though.
>
> How about running an LCD panel, transmitting and receiving data from a
> base-station 10s of miles away, interpreting incoming data packets,
> waiting for key presses? All for 10 mW.
Well, the distance to the base station doesn't matter unless it's
wireless, then it's just the transmitter power.
>> I know, for example, that the system I have here at my feet has an ATX
>> board, which means the "power" switch is solid state rather than a
>> physical switch. That means the board is powered all the time (when
>> the power supply switch is on at the back of the system).
>
> The main point is that mainboard and PSU makers have no incentive to
> make a low power and efficient "off" state. Really, such a small
> fraction of people/companies will make a decision based on the
> efficiency of the off state it is not worth it at all.
Very true.
Jim
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>> How about running an LCD panel, transmitting and receiving data from a
>> base-station 10s of miles away, interpreting incoming data packets,
>> waiting for key presses? All for 10 mW.
>
> Well, the distance to the base station doesn't matter unless it's
> wireless, then it's just the transmitter power.
I was just illustrating that a normal mobile phone can do all that stuff
(both transmitting and receiving to the base station) for around 10 mW.
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scott wrote:
>> Even so... that takes it up to, what, 19 mW? I don't know what the
>> other 3,981 W is for...
>
> Heat.
>
>> Convesly, the PC uses *less* power than I was expecting when turned
>> on, so...
>
> Is that with or without POV rendering? ;-)
Without *anything* happening, it uses 110 W.
With my stonking-great video card with a fan the size of a plannet, it
uses 190 W. (Roughly. It waivers a lot.) During the boot sequence it
tops 280 W. (Presumably when all those electric motors all start up at
once...)
Actually, what the heck...
http://blog.orphi.me.uk/about/power
(Table of my work so far.)
--
http://blog.orphi.me.uk/
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John VanSickle wrote:
>> Damn... pitty we can't use heat to do *useful* stuff!
>
> Heat already does useful things. For instance, it causes cute girls to
> wear skimpy clothing.
Hey, neat!
(Pitty it's too damn hot to do anything about it...)
--
http://blog.orphi.me.uk/
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>> Oh... no, not really. I mean, sound vibrations are really, *really*
>> tiny. (Think about it; even when the sound is turned up painfully
>> loud, the speaker cones move by such a tiny amount you can't even see
>> them move at all!)
>
> Huh? Even at normal listening volumes I can see the bass cones move on
> mine... Try feeding a 20 Hz sine wave in and watch the cone... These
> are only perhaps 6" drivers, nothing spectacular. Mind you, I have
> never noticed the tiny 2" cones move on my PC speakers.
I have never seen any cone on any speaker move visibly - no matter how
much physical pain my ears were in. See, human ears are, like, *really*
sensitive...
> Huh? You are saying that they deliberately make speakers less efficient
> so that a higher voltage can be used to drive them? I've never heard
> that before.
Yes.
> Also I have never seen much "serious" hi-fi rated at
> anything like 200 W for home use. IME 15 W per channel is plenty to
> fill a medium sized room very loudly, perhaps if you live in a very
> large house and like listening to music very loud you'd want 200 W.
Hmm, I think my amplifier (nothing special) is rated at 60 W per
channel. (IIRC, into 8 ohms at 1 kHz.)
That's 60 W RMS by the way. Not like the "100 W" portable thing I once
owned that was actually 0.5 W RMS. ;-)
>> The mater claims 249.98 V.
>
> Sounds ok to me, the voltage will fluctuate a lot depending on lots of
> factors, like how much power people are using around you etc. Try
> measuring the voltage at different times of the day...
Wait... the *voltage* changes depending on how much you use it? That's
odd. I thought that potential difference was always constant, and it's
only *current* that changes...
>> Also, 49.97 Hz. (So much for "they keep it to exactly 50 Hz to help
>> all those clocks that use it". The frequency waivers all over the place!)
>
> And you think your meter is accurate to +/- 0.03 Hz?
Actually, the instruction book (which is oddly large for such a simple
device) states the accuracy for all readings. I forget what it says for
the frequency...
--
http://blog.orphi.me.uk/
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Mueen Nawaz wrote:
> I find it interesting that you're focusing on power rather than
> energy. How long do you spend boiling water vs how long is the washer
> running?
Well, that's the other part. The fridge doesn't use much power, but it's
permanently switched on. (Altough obviously it only draws any current
now and then.) So far it's clocked up a fair number of kWh...
--
http://blog.orphi.me.uk/
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Orchid XP v3 wrote:
>>> I just find it bizzare that this huge washing machine, spinning away
>>> to violently that it's deafening to stand near and you'd probably be
>>> injured if you touched it, uses about 5% of the power of a teeny
>>> little kettle. Far out!
>>
>> And then you'd probably also be surprised how loud your speakers are
>> when you feed just 5 W into them.
>
> Oh... no, not really. I mean, sound vibrations are really, *really*
> tiny. (Think about it; even when the sound is turned up painfully loud,
> the speaker cones move by such a tiny amount you can't even see them
> move at all!)
>
have you taken into account that the overlap in frequency resolution of
your ears and eyes is very small? You can not hear anything below 20 Hz
or see anything above 50 Hz.
> AFAIK, the reason we have 200 W amplifiers and speakers isn't so much
> because it takes that much electricity to move air around, but to reduce
> RF pickup in the speaker wire... (Or rather, to reduce the
> *signifigance* of such pickup.)
>
>>> PS. 230 V? I thought it was 250 V...
>>
>> IIRC the spec was changed from 240 +/- 10% to 230 +15% -5% (or
>> something equally stupid) to get us inline with Europe.
At the same time the *rest* of Europe changed from 220 to exactly the
same specification. FYI the UK is *within* Europe.
>> Doesn't your meter tell you the voltage too?
>
> The mater claims 249.98 V.
>
> Also, 49.97 Hz. (So much for "they keep it to exactly 50 Hz to help all
> those clocks that use it". The frequency waivers all over the place!)
>
RTFM The instantaneous frequency (how is that for an oxymoron) may vary,
but there will be exactly 432000 cycles in a day.
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andrel wrote:
>> Oh... no, not really. I mean, sound vibrations are really, *really*
>> tiny. (Think about it; even when the sound is turned up painfully
>> loud, the speaker cones move by such a tiny amount you can't even see
>> them move at all!)
>>
> have you taken into account that the overlap in frequency resolution of
> your ears and eyes is very small? You can not hear anything below 20 Hz
> or see anything above 50 Hz.
And when I start up the engine of my car, the various parts move far too
fast for the eye to follow. But you *can* see the blur of moving
objects, and there is little doubt that they're moving. ;-)
>> Also, 49.97 Hz. (So much for "they keep it to exactly 50 Hz to help
>> all those clocks that use it". The frequency waivers all over the place!)
>>
> RTFM The instantaneous frequency (how is that for an oxymoron) may vary,
> but there will be exactly 432000 cycles in a day.
Behold: Differential calculus. ;-)
--
http://blog.orphi.me.uk/
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Orchid XP v3 wrote:
> Gee, I wonder what our lawn mower uses...
Mine has a nifty engine that breaks down all sorts of bio matter into
simple carbohydrates and then burns them. It's flexible enough to work
on matter as diverse as fruits, grains, and meats, although certain
spices have been known to give it trouble. Also, you need a fair amount
of fiber mixed in, otherwise the whole thing can get clogged.
--
...Ben Chambers
www.pacificwebguy.com
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Orchid XP v3 wrote:
> andrel wrote:
>
>>> Oh... no, not really. I mean, sound vibrations are really, *really*
>>> tiny. (Think about it; even when the sound is turned up painfully
>>> loud, the speaker cones move by such a tiny amount you can't even see
>>> them move at all!)
>>>
>> have you taken into account that the overlap in frequency resolution
>> of your ears and eyes is very small? You can not hear anything below
>> 20 Hz
>> or see anything above 50 Hz.
>
> And when I start up the engine of my car, the various parts move far too
> fast for the eye to follow. But you *can* see the blur of moving
> objects, and there is little doubt that they're moving. ;-)
Why do you think that those frequencies are far above 50 Hz?
What sound does your motor make? Can you find the base frequency on your
keyboard?
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"Orchid XP v3" <voi### [at] devnull> wrote in message
news:46dc4c7a$1@news.povray.org...
> John VanSickle wrote:
>
> >> Damn... pitty we can't use heat to do *useful* stuff!
> >
> > Heat already does useful things. For instance, it causes cute girls to
> > wear skimpy clothing.
>
> Hey, neat!
>
> (Pitty it's too damn hot to do anything about it...)
>
Two words...
Swimming pool
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On Mon, 03 Sep 2007 10:31:33 +0200, scott wrote:
>>> How about running an LCD panel, transmitting and receiving data from a
>>> base-station 10s of miles away, interpreting incoming data packets,
>>> waiting for key presses? All for 10 mW.
>>
>> Well, the distance to the base station doesn't matter unless it's
>> wireless, then it's just the transmitter power.
>
> I was just illustrating that a normal mobile phone can do all that stuff
> (both transmitting and receiving to the base station) for around 10 mW.
I *think* the xmit power of a cell phone is a bit more than that...But
I'd have to check.
Jim
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Jim Henderson wrote:
> I *think* the xmit power of a cell phone is a bit more than that...But
> I'd have to check.
Depends on the phone system. CDMA was originally designed to be an
undetectable transmitter for military use. IIRC, its power ranges
between 2.5mW and 5mw.
--
Darren New / San Diego, CA, USA (PST)
Remember the good old days, when we
used to complain about cryptography
being export-restricted?
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> Mine has a nifty engine that breaks down all sorts of bio matter into
> simple carbohydrates and then burns them. It's flexible enough to work on
> matter as diverse as fruits, grains, and meats, although certain spices
> have been known to give it trouble. Also, you need a fair amount of fiber
> mixed in, otherwise the whole thing can get clogged.
Rent-A-Ruminant?
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> Why do you think that those frequencies are far above 50 Hz?
50 Hz = 3000 rpm, but some of the parts like the valves only
move during a portion of a revolution, and have higher frequencies.
Camshafts are 2:1, I think, so if a lobe is about 30 degrees then
the upper frequency might be around (50*2*24)=2400 Hz sound
at 3000 rpm, or 160 Hz at a 200 rpm idle.
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Tim Attwood wrote:
>> Mine has a nifty engine that breaks down all sorts of bio matter into
>> simple carbohydrates and then burns them. It's flexible enough to work on
>> matter as diverse as fruits, grains, and meats, although certain spices
>> have been known to give it trouble. Also, you need a fair amount of fiber
>> mixed in, otherwise the whole thing can get clogged.
>
> Rent-A-Ruminant?
Nah, one of these :)
http://www.peoplepoweredmachines.com/reel_mower_landing.htm?gclid=CJjJm8adqY4CFQsEIwod4SvTSw
--
...Ben Chambers
www.pacificwebguy.com
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Gail Shaw wrote:
> "Orchid XP v3" <voi### [at] devnull> wrote in message
> news:46dc4c7a$1@news.povray.org...
>> John VanSickle wrote:
>>
>>>> Damn... pitty we can't use heat to do *useful* stuff!
>>> Heat already does useful things. For instance, it causes cute girls to
>>> wear skimpy clothing.
>> Hey, neat!
>>
>> (Pitty it's too damn hot to do anything about it...)
>>
>
> Two words...
>
> Swimming pool
One word: beach :)
--
...Ben Chambers
www.pacificwebguy.com
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>> I was just illustrating that a normal mobile phone can do all that stuff
>> (both transmitting and receiving to the base station) for around 10 mW.
>
> I *think* the xmit power of a cell phone is a bit more than that...But
> I'd have to check.
Sorry yes, that was average power for the whole phone, a phone can transmit
at higher powers (if you are in a very weak signal area) but only for a very
short time period (I guess just 1 packet every minute or so to let the base
stations in range know you are still there incase of an incoming call). Of
course if you are in a call average power use will be much higher, which is
why "talk-time" is something like 8 hours and "standby time" is usually a
week or so.
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> Without *anything* happening, it uses 110 W.
Ah good to know, it's roughly what I suspected...
> With my stonking-great video card with a fan the size of a plannet, it
> uses 190 W. (Roughly. It waivers a lot.) During the boot sequence it tops
> 280 W. (Presumably when all those electric motors all start up at once...)
It seems to me that before Windows gets going (or more specifically all the
device drivers) everything just runs in max power mode. Once Windows is in
charge of the PC it can then back things off like the GFX card and putting
the CPU in sleep mode when it's not needed.
OOC what power does it use when you're doing nothing in the BIOS settings
screen?
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>> Huh? You are saying that they deliberately make speakers less efficient
>> so that a higher voltage can be used to drive them? I've never heard
>> that before.
>
> Yes.
Interesting, how do they do that? Most speakers (electrically speaking)
seem very simple to me, just a cross-over network and then a coil of wire.
Hard to see how you could deliberately make the system less efficient
without just plonking a huge 50W resistor in series (which would totally
screw up the quality of the sound).
> Hmm, I think my amplifier (nothing special) is rated at 60 W per channel.
> (IIRC, into 8 ohms at 1 kHz.)
And what happens when you actually output 60 W in your room? BTW on most
amplifiers you need to get the input signal at the right level (not too high
or too low) to get the quoted maximum output power. I guess also your ears
work on a logarithmic scale, so 60 W is probably not as much "louder" than
20 W as you would think just by looking at the numbers.
> Wait... the *voltage* changes depending on how much you use it? That's
> odd. I thought that potential difference was always constant, and it's
> only *current* that changes...
That's only true if all the cables in the whole system have precisely zero
resistance, which they don't.
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Gail Shaw wrote:
>>> Heat already does useful things. For instance, it causes cute girls to
>>> wear skimpy clothing.
>> Hey, neat!
>>
>> (Pitty it's too damn hot to do anything about it...)
>>
>
> Two words...
>
> Swimming pool
Heh... I didn't know she was like that... ;-)
--
http://blog.orphi.me.uk/
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>>> Huh? You are saying that they deliberately make speakers less
>>> efficient so that a higher voltage can be used to drive them? I've
>>> never heard that before.
>>
>> Yes.
>
> Interesting, how do they do that?
You think *I* know?
> Hard to see how you could deliberately make the system less
> efficient without just plonking a huge 50W resistor in series (which
> would totally screw up the quality of the sound).
And why would that be?
>> Hmm, I think my amplifier (nothing special) is rated at 60 W per
>> channel. (IIRC, into 8 ohms at 1 kHz.)
>
> And what happens when you actually output 60 W in your room?
Well obviously I'm unlikely ever to try this. (It's like all toasters
have a special setting that transforms bread into charcole. We don't
know why, but they all have it.)
By the way... I notice with interest that the sound level drops
*dramatically* as you walk through the doorway. I mean, it's really
drastically quieter just slightly outside the door. I am be half-deaf
inside my room, and yet from outside it doesn't seem all that loud.
Really. You'd think the sound would travel more.
(Perhaps this is related to the mysterious "waves can't pass through
holes smaller than a certain size" phenominon?)
> BTW on
> most amplifiers you need to get the input signal at the right level (not
> too high or too low) to get the quoted maximum output power.
Yeah, probably.
(I once tried connecting a line-level output to the phono input. Big
mistake...)
> I guess
> also your ears work on a logarithmic scale, so 60 W is probably not as
> much "louder" than 20 W as you would think just by looking at the numbers.
Yeah, most human senses actually seem to work in a logarithmic way... I
suppose that means they work well under "all conditions" or something.
>> Wait... the *voltage* changes depending on how much you use it? That's
>> odd. I thought that potential difference was always constant, and it's
>> only *current* that changes...
>
> That's only true if all the cables in the whole system have precisely
> zero resistance, which they don't.
Really? How interesting...
--
http://blog.orphi.me.uk/
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>> And when I start up the engine of my car, the various parts move far
>> too fast for the eye to follow. But you *can* see the blur of moving
>> objects, and there is little doubt that they're moving. ;-)
> Why do you think that those frequencies are far above 50 Hz?
My engine *idles* at several thousand RPM...
> What sound does your motor make? Can you find the base frequency on your
> keyboard?
Surely that's just the resonant modes of the exhaust system and the chasis?
--
http://blog.orphi.me.uk/
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scott wrote:
>> Without *anything* happening, it uses 110 W.
>
> Ah good to know, it's roughly what I suspected...
Pretty tiny compared to the 20 W or so my laptop uses when idling.
(But then... no 3D graphics, only 1 HD, lower clock speed, etc.)
>> With my stonking-great video card with a fan the size of a plannet, it
>> uses 190 W. (Roughly. It waivers a lot.) During the boot sequence it
>> tops 280 W. (Presumably when all those electric motors all start up at
>> once...)
>
> It seems to me that before Windows gets going (or more specifically all
> the device drivers) everything just runs in max power mode. Once
> Windows is in charge of the PC it can then back things off like the GFX
> card and putting the CPU in sleep mode when it's not needed.
>
> OOC what power does it use when you're doing nothing in the BIOS
> settings screen?
Hmm, I'll go check it out sometime...
BTW, when I installed Linux on my dad's laptop, we discovered something
interesting. We tried to install the software, but the machine began to
behave more and more strangely. Eventually I noticed that the laptop was
utterly *scalding* hot to the touch. We rebooted it, and the various
fans immediately kicked in at full power.
We discovered that if you boot into Linux while the fans are off, they
stay off. And if they're running when Linux starts, they stay running -
no matter how cold the machine gets. Weird, eh?
Once the laptop was cold, Linux installed just fine...
--
http://blog.orphi.me.uk/
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Orchid XP v3 wrote:
>>> And when I start up the engine of my car, the various parts move far
>>> too fast for the eye to follow. But you *can* see the blur of moving
>>> objects, and there is little doubt that they're moving. ;-)
>
>> Why do you think that those frequencies are far above 50 Hz?
>
> My engine *idles* at several thousand RPM...
The significant character here is 'M'
>
>> What sound does your motor make? Can you find the base frequency on
>> your keyboard?
>
> Surely that's just the resonant modes of the exhaust system and the chasis?
>
Whatever it is, that is what you see. If it moves faster than 50 Hz you
either see it not moving at all or, viewed in the right direction, as a
semitransparent surface. If you can prove that you can see something
moving at, say 200 Hz, I have a couple of friends working on the retina
that would be most interested in such a physiological anomality. ;)
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>>> Why do you think that those frequencies are far above 50 Hz?
>>
>> My engine *idles* at several thousand RPM...
> The significant character here is 'M'
Hmm. What is 2,000 RPM in Hz? 33 Hz? That's interesting...
>>> What sound does your motor make? Can you find the base frequency on
>>> your keyboard?
>>
>> Surely that's just the resonant modes of the exhaust system and the
>> chasis?
>>
> Whatever it is, that is what you see. If it moves faster than 50 Hz you
> either see it not moving at all or, viewed in the right direction, as a
> semitransparent surface.
AFAIK, the retina sees the "integral" of incident light over time,
roughly. So I'm not sure why an object moving fast enough would appear
to stop moving. Become invisible, perhaps, if it's small enough...
> If you can prove that you can see something
> moving at, say 200 Hz, I have a couple of friends working on the retina
> that would be most interested in such a physiological anomality. ;)
How about my tuning fork? That says "440 Hz" on it, and I can see that
vibrating plainly enough... ;-)
(Oddly though, it doesn't seem to make much audible sound, despite the
ends of the fork traversing really quite some distance. I can only
surmise that it doesn't move the air around very much or something...)
--
http://blog.orphi.me.uk/
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Orchid XP v3 wrote:
>>>> Why do you think that those frequencies are far above 50 Hz?
>>>
>>> My engine *idles* at several thousand RPM...
>> The significant character here is 'M'
>
> Hmm. What is 2,000 RPM in Hz? 33 Hz? That's interesting...
>
>>>> What sound does your motor make? Can you find the base frequency on
>>>> your keyboard?
>>>
>>> Surely that's just the resonant modes of the exhaust system and the
>>> chasis?
>>>
>> Whatever it is, that is what you see. If it moves faster than 50 Hz
>> you either see it not moving at all or, viewed in the right direction,
>> as a semitransparent surface.
>
> AFAIK, the retina sees the "integral" of incident light over time,
> roughly.
Not really
> So I'm not sure why an object moving fast enough would appear
> to stop moving. Become invisible, perhaps, if it's small enough...
>
>> If you can prove that you can see something moving at, say 200 Hz, I
>> have a couple of friends working on the retina that would be most
>> interested in such a physiological anomality. ;)
>
> How about my tuning fork? That says "440 Hz" on it, and I can see that
> vibrating plainly enough... ;-)
Again the question is if you see the 440 Hz or a much lower frequency
wobble. The ends of the fork should be a little wider and a little
transparent. Anyway I think what you see is that it is moving, not the
movement itself.
>
> (Oddly though, it doesn't seem to make much audible sound, despite the
> ends of the fork traversing really quite some distance. I can only
> surmise that it doesn't move the air around very much or something...)
>
Perhaps otherwise it would loose energy too fast and the tone would die
out quickly.
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"andrel" <a_l### [at] hotmailcom> a écrit dans le message de news:
46D### [at] hotmailcom...
>>
>> (Oddly though, it doesn't seem to make much audible sound, despite the
>> ends of the fork traversing really quite some distance. I can only
>> surmise that it doesn't move the air around very much or something...)
>>
> Perhaps otherwise it would loose energy too fast and the tone would die
> out quickly.
Think of a big impedance mismatch between the fork and air.
You get a better match when you put the round end on a thin hard surface as
a guitar top or a box.
Then the vibrating surface is much bigger and can transmit energy to the
air.
Note that the sound dies faster then.
Marc
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On Tue, 04 Sep 2007 10:13:37 +0200, scott wrote:
> Of course if you are in a call average power use will be much higher,
> which is why "talk-time" is something like 8 hours and "standby time" is
> usually a week or so.
I don't know anyone who gets that kind of standby time. My phone (which
is fairly new) only gets about a day, maybe two of standby time. Course
I use it for other things (like navigation) which cut down on the
available battery, natch.
Jim
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On Mon, 03 Sep 2007 16:40:09 -0700, Darren New wrote:
> Depends on the phone system. CDMA was originally designed to be an
> undetectable transmitter for military use. IIRC, its power ranges
> between 2.5mW and 5mw.
That sounds like the range I was thinking of. 1 mW isn't very much.
Jim
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"Orchid XP v3" <voi### [at] devnull> wrote in message
news:46dda414$1@news.povray.org...
>>> And when I start up the engine of my car, the various parts move far too
>>> fast for the eye to follow. But you *can* see the blur of moving
>>> objects, and there is little doubt that they're moving. ;-)
>
>> Why do you think that those frequencies are far above 50 Hz?
>
> My engine *idles* at several thousand RPM...
No it doesn't!
What kind of engine do you run in your car??? a nitro engine???
Any car engine is capable of idling far below 1000rpm. Most idle aroun
600-800rpm depending on auto or manual gearbox...
HTH
Cheers Dre
>> What sound does your motor make? Can you find the base frequency on your
>> keyboard?
>
> Surely that's just the resonant modes of the exhaust system and the
> chasis?
>
> --
> http://blog.orphi.me.uk/
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> Nah, one of these :)
>
>
http://www.peoplepoweredmachines.com/reel_mower_landing.htm?gclid=CJjJm8adqY4CFQsEIwod4SvTSw
Ah, I thought they ran on beer =)
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Gail Shaw wrote:
> "Orchid XP v3" <voi### [at] devnull> wrote in message
> news:46dc4c7a$1@news.povray.org...
>
>>John VanSickle wrote:
>>
>>
>>>>Damn... pitty we can't use heat to do *useful* stuff!
>>>
>>>Heat already does useful things. For instance, it causes cute girls to
>>>wear skimpy clothing.
>>
>>Hey, neat!
>>
>>(Pitty it's too damn hot to do anything about it...)
>>
>
>
> Two words...
>
> Swimming pool
Which results in--even skimpier clothing! Win-win!
Regards,
John
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Dre wrote:
> No it doesn't!
>
> What kind of engine do you run in your car??? a nitro engine???
>
> Any car engine is capable of idling far below 1000rpm. Most idle aroun
> 600-800rpm depending on auto or manual gearbox...
I've seen several engines that idle at more than 1000rpm. I even saw
one go as high as 1 800 (though I'm pretty sure there was something
wrong with it).
--
...Ben Chambers
www.pacificwebguy.com
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Orchid XP v3 wrote:
> AFAIK, the retina sees the "integral" of incident light over time,
Errr, not even close. Indeed, if something is completely still, you
can't see it at all. That's why your eyes are always moving (saccades).
--
Darren New / San Diego, CA, USA (PST)
Remember the good old days, when we
used to complain about cryptography
being export-restricted?
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Chambers wrote:
> Dre wrote:
>> No it doesn't!
>>
>> What kind of engine do you run in your car??? a nitro engine???
>>
>> Any car engine is capable of idling far below 1000rpm. Most idle
>> aroun 600-800rpm depending on auto or manual gearbox...
>
> I've seen several engines that idle at more than 1000rpm. I even saw
> one go as high as 1 800 (though I'm pretty sure there was something
> wrong with it).
>
My 4 stroke, 49.9 cc moped engine idles at 1800 to 2200. That is, if the
manual is to be trusted, since in all three places it lists an ideal
idle speed it has a different number. But, there is a difference between
cars, and chainsaw motors with wheels.
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"Chambers" <ben### [at] pacificwebguycom> wrote in message
news:46de0bbd@news.povray.org...
> Dre wrote:
>> No it doesn't!
>>
>> What kind of engine do you run in your car??? a nitro engine???
>>
>> Any car engine is capable of idling far below 1000rpm. Most idle aroun
>> 600-800rpm depending on auto or manual gearbox...
>
> I've seen several engines that idle at more than 1000rpm. I even saw one
> go as high as 1 800 (though I'm pretty sure there was something wrong with
> it).
>
> --
> ...Ben Chambers
> www.pacificwebguy.com
Well car engines tend to idle higher when they are cold as the ecu tells
them to (engines dont like being cold). An engine at operating temp
shouldn't need to idle above 1000rpm, thats just a waste of fuel.
1800rpm is way too high for idle and as you say, there was something wrong
with it.
I was just pointing out to Orchid that his engine *doesn't* idle at
*several* thousand rpm, thats a gross exaggeration.
Cheers Dre
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"Sabrina Kilian" <"ykgp at vtSPAM.edu"> wrote in message
news:46de1a62$1@news.povray.org...
> Chambers wrote:
>> Dre wrote:
>>> No it doesn't!
>>>
>>> What kind of engine do you run in your car??? a nitro engine???
>>>
>>> Any car engine is capable of idling far below 1000rpm. Most idle
>>> aroun 600-800rpm depending on auto or manual gearbox...
>>
>> I've seen several engines that idle at more than 1000rpm. I even saw
>> one go as high as 1 800 (though I'm pretty sure there was something
>> wrong with it).
>>
>
> My 4 stroke, 49.9 cc moped engine idles at 1800 to 2200. That is, if the
> manual is to be trusted, since in all three places it lists an ideal
> idle speed it has a different number. But, there is a difference between
> cars, and chainsaw motors with wheels.
Exactly, my model nitro engines need idle (2.5cc) idle around 2000-3000rpm
otherwise they stall, but they are a little different to a car engine, size
and rotating mass tend to have a lot to do with that :)
Cheers Dre
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On Tue, 04 Sep 2007 19:22:04 -0700, Darren New wrote:
> Orchid XP v3 wrote:
>> AFAIK, the retina sees the "integral" of incident light over time,
>
> Errr, not even close. Indeed, if something is completely still, you
> can't see it at all. That's why your eyes are always moving (saccades).
*That's* how an SEP field works. I always wondered. ;-)
Jim
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> I don't know anyone who gets that kind of standby time. My phone (which
> is fairly new) only gets about a day, maybe two of standby time.
Oh wow, that would annoy the hell out of me if I had to charge my phone
every 24-48 hours... Mine usually lasts about 5 days with a few texts and
short calls per day. I do make sure that bluetooth is turned off when I'm
not actively using it though, maybe that makes a difference?
I know my mum had to charge her old phone every 24 hours or it would die,
but she got a new battery for it and it went back to lasting for ages again
.. but yours is new.. hmmm, what make/model is it?
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>> Hard to see how you could deliberately make the system less efficient
>> without just plonking a huge 50W resistor in series (which would totally
>> screw up the quality of the sound).
>
> And why would that be?
Because if you put a resistance in there large enough to causes a
significant change in efficiency it would create a low pass filter with the
capacitance of the cable. Also the resistor would heat up, so if you
listened to loud music, after a while it would start to get quieter, and
your speakers would start to get warmer... Doesn't seem like a good idea if
you are striving for optimum sound quality...
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>> What sound does your motor make? Can you find the base frequency on your
>> keyboard?
>
> Surely that's just the resonant modes of the exhaust system and the
> chasis?
Ermm, rev your engine, notice how the pitch of the sound corresponds to the
rpms? Some part of the sound will be due to resonances in the system, but
there will be a obvious frequency component (and harmonics) that are equal
to the rpm (that obviously change with engine speed).
Actually Formula 1 teams use this exact method to check what RPM their
competitors' cars are achieving. From the RPM trace they can estimate the
power output of the engine (given they know the speed of the car, and that
all F1 cars weigh the same).
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"Dre" <aus### [at] hotmailcom> a écrit dans le message de news:
46de288a@news.povray.org...
>
>but they are a little different to a car engine, size and rotating mass
>tend to have a lot to do with that :)
And number of cylinders as well
Marc
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scott wrote:
>> I don't know anyone who gets that kind of standby time. My phone (which
>> is fairly new) only gets about a day, maybe two of standby time.
>
> Oh wow, that would annoy the hell out of me if I had to charge my phone
> every 24-48 hours... Mine usually lasts about 5 days with a few texts
> and short calls per day. I do make sure that bluetooth is turned off
> when I'm not actively using it though, maybe that makes a difference?
I put my phone into flight mode for over a week when I was in the States
for a conference recently, because I didn't want to use it for anything
other than an alarm clock. It was switched on for the entire time, and
the battery level only went down by about 10-15%.
This seems to indicate that even on standby, a cellphone uses a
considerable amount of power simply staying in contact with the network.
I reckon if I only connected it to the network to make calls, the
battery could last up to a month.
I'm not sure bluetooth makes that much difference, because it's not
nearly as active.
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"scott" <sco### [at] laptopcom> a écrit dans le message de news:
46de46c6@news.povray.org...
>>> Hard to see how you could deliberately make the system less efficient
>>> without just plonking a huge 50W resistor in series (which would totally
>>> screw up the quality of the sound).
>>
>> And why would that be?
>
> Because if you put a resistance in there large enough to causes a
> significant change in efficiency it would create a low pass filter with
> the capacitance of the cable. Also the resistor would heat up, so if you
> listened to loud music, after a while it would start to get quieter, and
> your speakers would start to get warmer... Doesn't seem like a good idea
> if you are striving for optimum sound quality...
>
Some power enclosures come with a built-in kind of protection : a light-bulb
in serie with the speakers. When input power increases, the bulb wire gets
hot then its resistance increases and the voltage at the ends of the coil
is limited.
Marc
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"scott" <sco### [at] laptopcom> a écrit dans le message de news:
46de58a3@news.povray.org...
(given they know the speed of the car, and that
> all F1 cars weigh the same).
But not the same Cx
Marc
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