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On Sun, 02 Sep 2007 22:05:17 +0200, Orchid XP v3 <voi### [at] dev null> wrote:
>>> 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. Doesn't your
>> meter tell you the voltage too?
>
> The mater claims 249.98 V.
Still within tolerance.
http://en.wikipedia.org/wiki/Mains_electricity#Voltage_levels
> 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!)
http://en.wikipedia.org/wiki/Mains_electricity#Frequency_stability
http://www.dynamicdemand.co.uk/grid.htm
--
FE
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Orchid XP v3 wrote:
>>> Can anybody suggest why this might be?
>>
>>
>> It's because heat represents a huge amount of energy.
>>
>> For instance, the humble calorie, the amount of energy required to
>> raise a single gram of water by one degree celsius, is the same amount
>> of energy required to lift that same gram of water about 387 meters in
>> Earth's gravity, or accelerate it from zero to 87 meters per second.
>
> 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.
Regards,
John
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On Sun, 02 Sep 2007 20:58:04 +0100, Orchid XP v3 wrote:
> I really, *really* hope I have that
> disabled though... (It's hard to tell!)
BIOS settings. But it's not exactly easy to learn the wake-up code from
outside a NATted connection. You've got to know the MAC address of the
system, IIRC.
Yep, according to http://en.wikipedia.org/wiki/Wake-on-LAN the magic
packet is set over a connectionless protocol (UDP, IPX) with "FF FF FF FF
FF FF FF" (in hex, hopefully obviously) plus 16 repetitions of the target
machine's MAC address, plus a 4-6 byte password.
So I don't think you have to worry about me turning your machine on from
half a world away.
Jim
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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] nawazorg<<<<<<
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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