Here is a schematic I'm planning to make (right click on the image and 'open image in new tab' to see it better'):
I have a transformer and AC to DC converter that makes +/-12V.
(1) Does 'power supply 1' correspond to the +12V wire and 'power supply 2' to the -12V wire?
(2) When I see the symbol 'ground' on the schematic does that mean that I need to connect those to the -12V line? I have no 0 volt line in the circuit so what is the ground line?
(3) Why are C3, C5 non-polarized capacitors and why are the other ones polarized? The current flows from negative to positive. Does that mean that the polarized capacitors need to be placed with their positive legs pointing to the left?
I already asked the grounding question but I got only answers that were theory. I would like specifically to know how do I deal with grounding in this circuit and why there is no grounding symbol in an arbitrary "powering an LED with a 9V battery" circuit.
Thank you very much. This will clarify a lot of things for me.