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Voltage Divider - help with simple AC circuit

As you'll gather quickly enough, I'm a novice, and I would appreciate the guidance of someone experienced in electronic circuit design.

I would like to build a simple Voltage divider circuit. I want to take the single phase 120VAC, 15A, 60Hz out of my wall and step down the voltage/current to around 2 - 4VAC & 1A - 1.4A. My goal is to feed this signal into my audio converters so I can see the constituent harmonic energies and other noise in the mains AC. I would like to read from 1Hz to 20kHz.

I'm guessing the easiest way to do this would be to use a transformer, but as I understand it, transformers don't handle frequencies equally. So I'm thinking a resistor-based circuit might do it. Do they make resistors that could dissipate that much energy safely? (i.e., 1800W less approx. 5.6W). Is it that easy...? (My suspicion is that nothing ever is) I would also like to build in a fuse so that a transient in the mains doesn't blow my converters!!!

There is also the possibility of a zener diode-based circuit, but I'm unsure whether the diode would introduce unwanted changes to the frequency spectrum, as in the case of transformers.

Your help is very much appreciated.

Reply to
Beside Myself
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WARNING.

Any resistive divider will be ALIVE and could kill you.

Transformer isolation is probably the only way but you sound to be too novice to mess with this stuff till you learn more about electricity.

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John G

Wot\'s Your Real Problem?
Reply to
John G

Run it thru a step down transformer. That's how it get to the 120V rms in the first place.

Reply to
GotCoffee

As others have already commented, this approach may be less than optimal.

The elephant in the room that doesn't seem to be addressed is: Why?

If this is just for curiosity then your best approach is to grab an old wall wart with an AC output and run it through a current limiting resistor and a pot to your line-in jack. You'll see 60 Hz, a bunch of noise of no particular significance, and your curiosity will be satisfied (and you and the equipment are likely to survive).

If this is "for work" then rent or buy a system that does this properly.

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has several that could be appropriate.

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Rich Webb   Norfolk, VA
Reply to
Rich Webb

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