How can I make an easy power supply?
I want to make a really easy power supply that uses direct line voltage (120) using just a capacitor(WITHOUT a transformer). I've seen the instructable where Tool Using Animal (http://www.instructables.com/id/LED-Lightbulb/) made one for LEDS. I measured it and got around 2 volts. That was with a .47uf cap. I want to get around 12 volts but I don't know how to get it without buying 20 different caps to see which one works. Is there a formula? Thanks in advance for your help..
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Notice that also uses a "1/4 watt 1kilo ohm resistor" - like others I don't think you should try this sort of thing.
L
. I have to agree with the others on this one: you obviously don't know enough about electrical safety to be messing with mains voltage and/or an unisolated power supply.
. Your best bet is to get a mains-to-~14V transformer, a rectifier bridge, and a 12V regulator.
. Your best bet is to get a mains-to-~14V transformer, a rectifier bridge, and a 12V regulator.
Dec 27, 2010. 10:39 AMRe-design
says:
Making a power supply like this to use in other than a totally shielded way is incredibly dangerous.
Any hobby power supply should include a transformer with separate primary and secondary windings. Using wall power like this would become 120 volts a/c should the capacitor short out and they often short out.
A 14 volt transformer can be had for less than $10 or free if you scavenge a bit and is infinitely safer than what you propose.
With all due respect, I hope no one has the lack of common sense to give you any details.
Any hobby power supply should include a transformer with separate primary and secondary windings. Using wall power like this would become 120 volts a/c should the capacitor short out and they often short out.
A 14 volt transformer can be had for less than $10 or free if you scavenge a bit and is infinitely safer than what you propose.
With all due respect, I hope no one has the lack of common sense to give you any details.
A non-isolated power supply is not something suitable for hobbyist use: it is essentially at mains voltage and can easily be lethal.
Steve
Steve
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