Electronic – Function generator as a DC power supply

acdcfunction generatorpower supplysafety

I'm wanting to start my own lab at home so that I can learn things faster than uni teaches (we're not allowed into labs unless we're in our own lab).

A friend said that I'd be better off getting a power supply than a function generator, since I'm a first/second year elec student because he thought they'd be cheaper, but there's only about $50 difference between the two.

I'm actually wondering whether it would be a good idea to get the Rigol DG-1022, and to supply a dc source, I set the frequency as close to zero as possible. Of course, electricity is dangerous; while I'm cool with blowing an LED or op-amp, I'm not at all happy to assume that a mock dc supply is actually direct current, without first checking if this is safe.

Wondering what you think? I'm not just asking about safety, if you've got other comments, I'm happy to hear them.

Best Answer

No, that won't work.

You could use fixed voltage supplies (AC adapters, wall warts) for most power supply purposes - just understand that your circuits are living dangerously if the supplies aren't current limited, so be careful and double-check your connections - until you can afford an adjustable PSU.

One option is to make one of your first projects an adjustable PSU with current limiting (using an LM317 and a heatsink) powered by an AC adaptor, perhaps a 19V one from an old laptop. It'll teach you about proper heatsinking!

So I'd still go for the function generator as a first purchase (assuming you already have a multimeter!) but use other arrangements to supply power.