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Starting the cabinet all at once. It works! And here's how...

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danny_galaga:
i should just point out here for any who arent familiar with electronic parts is that a capacitor wants to absorb energy instantly. its like a battery that instantly charges or discharges. so when its not charged it behaves like a short. once it has charged up to the applied voltage its voltage potential is the same as the applied voltage and so it behaves as if its open circuit. its not often desirable to have it charge or discharge instantly (for instance, my watch is a seiko kinetic. its powered by a capacitor which is charged up by a swinging weight). luckily adding resistance to the circuit slows it down proportional to the resistance.
just mentioning this in case anyone wondered how it works. there are no moving parts.

independentthread:

--- Quote from: danny_galaga on June 26, 2004, 08:57:24 am ---its not often desirable to have it charge or discharge instantly
--- End quote ---

This once again begs the question, is it not disrable for for JUST the capacitor, or will it harm the motherboard in time?  I live in an apartment complex where people consistently buy replacement electronics and have the decency to leave the old ones NEXT to the dumpster.  I have an endless supply of junk television sets and broken radios and the like.  If the capcitor is the the only thing that is going to be damged, the only tears I might cry will be from sweat dripping in my eye as I rip apart a 30 year old TV cabinet.

SirPeale:
No damage will come to the motherboard.  It's just releasing the current (which is miniscule) which was built up in it.  Really, the cap is so tiny.  Just make sure you use a cap that's rated small (like 10uF)

independentthread:
Awesome, I'm taking mine that route then.

danny_galaga:
i guess this is why im not a college lecturer!! Im always forgetting things in my explanations. The two reasons its not desirable is that you usually want to have a timed charge or discharge, and yes in some cases the second reason is that it might cause damage somewhere else. Its safe  in the situation on the motherboard because 1) there is already a high effective resistance in that circuit and 2) as Peale said you are using a fairly small capacitance. The time is effected by capacitance x resistance. Capacitors have very small ratings. This keeps the formula simple since it is ohms x farads = time in seconds. The measurements for resistance and time (ohms and seconds) already existed when capacitance was first measured, so that means a farad is quite large. I think a 1 Farad cap would be roughly the size of a filing cabinet and would probably discharge through a brick wall!!

edit: i've since found i was way off on the cap size. it seems a 1 farad cap is about the size of two cans of beer end to end (low voltage rating for stereos).

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