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>> So there we are. *Clearly* I have too much free time...
>
> ...business as usual, eh? :-} Some things never change...
...and some things do. Looks like I'm actually going to be *busy* today
for a change. o_O
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Invisible wrote:
>>> So there we are. *Clearly* I have too much free time...
>>
>> ...business as usual, eh? :-} Some things never change...
>
> ...and some things do. Looks like I'm actually going to be *busy* today
> for a change. o_O
Except that so far, I've spent the whole morning *waiting* for other
people to do their jobs before I can get started on mine! >_<
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Invisible wrote:
> scott wrote:
>>> BTW, what *are* those absurdly tiny 2-pin devices scattered all over
>>> the board? Resisters? Many of them have labels printed on the board
>>> such as "R7". But a few are labelled "C13" or similar...
>>
>> Yes, take a wild guess what R and C stand for :-)
>
> I was under the impression that capacitors have to be of a specific
> physical size in order to have the correct capacitance...
Only caps used for filtering power supplies need to be in the millifarad
range, and these will be quite large (the size of an AA battery or even
larger). Caps used for filtering low-level electronic signals,
especially at high frequencies, are often in the picofarad range (and
will range in size between the size of a grain of rice to that of a
small tablet of aspirin).
Regards,
John
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John VanSickle wrote:
> Only caps used for filtering power supplies need to be in the millifarad
> range,
A friend of mine had a 2 farad capacitor installed near his house to suck up
lightning strikes. About the size of a 55-gallon drum.
--
Darren New, San Diego CA, USA (PST)
There's no CD like OCD, there's no CD I knoooow!
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Darren New wrote:
> About the size of a 55-gallon drum.
And for those of you in metric lands, this is the size of a barrel in video
games. :-)
--
Darren New, San Diego CA, USA (PST)
There's no CD like OCD, there's no CD I knoooow!
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>> About the size of a 55-gallon drum.
>
> And for those of you in metric lands, this is the size of a barrel in
> video games. :-)
WIN!
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Darren New wrote:
> A friend of mine had a 2 farad capacitor installed near his house to
> suck up lightning strikes. About the size of a 55-gallon drum.
I thought that's what an avalanche diode was for? Or is this connected
to a lightning rod? I'd sure hate to short the terminals on that after
charging it up !!
I've seen 1F caps in car audio shops, basically used to provide lots of
current to the amp when power is needed for strong transients (e.g. Bass
drum hit.) I'm sure it filters pretty much any ripple generated by the
alternator, too.
--
~Mike
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Mike Raiford wrote:
> I thought that's what an avalanche diode was for? Or is this connected
> to a lightning rod? I'd sure hate to short the terminals on that after
> charging it up !!
It was hooked to a ham radio antenna that was rather larger in surface area
than his house was. I don't know the details, but I think the idea was that
it would absorb the strike, then promptly melt, grounding it out. Or something.
--
Darren New, San Diego CA, USA (PST)
There's no CD like OCD, there's no CD I knoooow!
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On 24-4-2009 15:50, Darren New wrote:
> Darren New wrote:
>> About the size of a 55-gallon drum.
>
> And for those of you in metric lands, this is the size of a barrel in
> video games. :-)
>
>
And for those metric and who don't play video games?
Even for a cell membrane (one of the best capacitors known to man IIRC)
you'd still need a surface of 200 m2, about half a basketball court, for
that.
Once I was in a lab when suddenly there was a load bang from a room
somewhere else in the building. As load as a gunshot or louder (haven't
heard one of those IRL, so I am just guessing). Casual comment from the
guy I was with: oh it's only Martin. This Martin was doing experiments
with a laser and he needed some capacitors of a more than a liter (the
size of a large coke-bottle). Apparently every now and then one did explode.
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Mike Raiford wrote:
> Darren New wrote:
>
>> A friend of mine had a 2 farad capacitor installed near his house to
>> suck up lightning strikes. About the size of a 55-gallon drum.
>
> I thought that's what an avalanche diode was for? Or is this connected
> to a lightning rod? I'd sure hate to short the terminals on that after
> charging it up !!
>
> I've seen 1F caps in car audio shops, basically used to provide lots of
> current to the amp when power is needed for strong transients (e.g. Bass
> drum hit.) I'm sure it filters pretty much any ripple generated by the
> alternator, too.
Here, have some 300F caps :)
http://www.maxwell.com/ultracapacitors/products/
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