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How to Generate a FLuctuating Voltage

How to Generate a FLuctuating Voltage

How to Generate a FLuctuating Voltage

(OP)
Is there a device on the market that I can use to create a modulating voltage at low currents (100-500mA). I want to do this first on a bench, then from a DC voltage source.

I don't know the V-range, or the frequency I need. That will be determined from bench testing.

My initial thought was a "black box" already exists that will accomplish this for me. Is this correct, or will I need to design a circuit to create this output?

RE: How to Generate a FLuctuating Voltage

You probably know if you are in the 10 V or 500 V range? And frequency around 10 - 100 Hz or 10 kHz - MHz?

Gunnar Englund
www.gke.org
--------------------------------------
100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...

RE: How to Generate a FLuctuating Voltage

(OP)
My initial guess is 10-200V, at maybe 200 cycles per second at a fairly constant current in the range of 200-500mA.

RE: How to Generate a FLuctuating Voltage

That would equal something like 100 watts, maximum. And the frequency range is well within the bandwidth of an ordinary HiFi sound amplifier. You can get the voltage level needed by using a transformer. The frequency is a little high for normal mains transformers. The core get a little warm, but a fan usually takes care of that.

You need an input signal for the amplifier. The obvious choice is a programmable arbitrary generator. But you can use anything that delivers a low level signal that does what you want. There are freeware signal generator programs on the web. You can then generate the signal in your computer and use the earphone output to couple it to the amplifier. Possibilities are countless.

Gunnar Englund
www.gke.org
--------------------------------------
100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...

RE: How to Generate a FLuctuating Voltage

Thanks Keith. Ain't it wonderful what you kan do with simple devices found in every kitchen?

Gunnar Englund
www.gke.org
--------------------------------------
100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...

RE: How to Generate a FLuctuating Voltage

Yeah Gunnar!

I keep a one channelized stereo amp on the shelf for just such abuse.

Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com

RE: How to Generate a FLuctuating Voltage

Hi Keith and Gunnar. I like kitchen solutions also. Good suggestion.
Yours
Bill

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