This is a very basic low ripple power supply, perfect for audio use. Regulated positive and negative voltage.

You will need to use a centre tapped transformer for this to work… eg 15v-0v-15v

Change R1 R2 R3 & R4 resistors to get different output voltage.

Some examples, with E12 (10%) resistors:

3.3V: 1k2 + 1k8 →→ 3% error

5V: 270 Ω + 820 Ω →→ 2% error

9V: 560 Ω + 3k3 →→ 2% error

12V: 390 Ω + 3k3 →→ less than 1% error

15V: 1k2 + 12k →→ 4% error

24V: 560 Ω + 10k →→ less than 1% error

For comparison, with E96 (1%) resistors, all of the following have less than 1% error:

3.3V: 365 Ω + 590 Ω

5V: 1k02 + 2k94

9V: 71.5 Ω + 442 Ω

12V: 392 Ω + 3k32

15V: 590 Ω + 6k34

24V: 1k24 + 21k5

A nice resistor calculator can be found HERE for this circuit…

For exact values check the calculator.

Etch at Home File available HERE

C1 & C7 50v 1000uf

C2 & C8 10uf 63V

Diodes 1N4004

Rectifier KBP01

C3 C4 C9 & C10 4700uf – 10000uf 25v

C5 & C11 1uf

C6 & C12 0.1uf

You can solder wires directly to the board but screw in terminals are recommended.