Which would be easier to use?

Which would be easier to use in a circuit:
the CRT of a TV set to hold a massive amount of electrical charge
a capacitor with a similar amount of holding capacity (capacitance, if I'm correct)?

If it's the CRT from a TV, how would one go about using it as a capacitor?

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lemonie8 years ago
What do you want to do, in real terms? L
Seconded. It's easy to deliver a high voltage ; every time you shuffle your feet across a carpet during winter you're up into the thousands of volts range; standard static-electric generators and tesla coils and so on can go much higher... but that's like saying it's easy to lift a teaspoonful of water to the top of the empire state building; the actual amount of energy stored depends on how much charge (or water) has been raised to that potential. Small capacitors typically have "breakdown voltages" (the point at which they give up and discharge themselves) around 600 volts. A leyden jar can hold a much higher voltage but not much charge. You'd basically be using the picture tube as a leyden jar. So: Neither approach seems particularly likely to hold "a massive amount of electrical charge". The CRT, used as a leyden jar, will probably hold more charge than a cheap capacitor. But whether either will work at all in your circuit depends on what the circuit is trying to do. You may really be better off with honking big capacitors, or batteries.
robotguy4 (author)  orksecurity8 years ago
I'm looking for something for a railgun. I believe that just a battery won't work that well...
appolo8 years ago
CRT's as used for TV have a typical final anode voltage of around 24kV. The CRT can store this charge as a capacitor due to it's construction. The CRT bowl has a metallised internal and external coating separated by the glass carcass known as the dielectric substrate. So you have your capacitor capable of storing this high voltage charge for some considerable time! I don't know of any equivalent capacitors available for the home constructor... As Lemonie asks_ what do you intend to do? maybe we can advise further.
robotguy4 (author)  appolo8 years ago
Basically: Railgun. I'm not sure what you want for maximum velocity (charge? voltage? ... AWESOME?!?!). I've been hurting my right hand trying to figure it out...
seandogue8 years ago
a capacitor, or even better, since no holding voltage was specified, a battery. I would not be inclined to use a CRT as a capacitor under any circumstances.