Symmetrical Power Supply from NonCT Transformer

As a technician and hobbyists, we are often faced with the problem of for the need the type of a voltage, where we had just the kind of asymmetric (+ and 0 V) while needs symmetrical (+, - and 0 V).



From the many circuits that I know, usually electronics friends make the power supply circuit from AC voltage asymmetric (NonCT) become a symmetrical voltage (+, 0, -) use IC L165 as the