I'd like to design and construct a circuit. Where do i start?
By deciding what you want it to do.
If you really dont know what to do, set yourself a simple task that has a practical objective then maybe think about using circuit simulating software (unless you have the hardware voltmeters, oscillascope etc) then buy a soldering iron and make it for real. Oh btw if you are thinking about doing anything that is plugged into the mains do some research first, almost gave myself a free treatment of electric shock therapy the other day ;)
EDIT: probably best to keep away from transformers and large capacitors in general to stat with
what type of circuit are trying to make electronic or electrical there is a difference
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