A transformer that is step down 230 Volt to 15 Volts across a center tapped secondary winding i.e, 15 VAC individually across the two halves of the secondary winding i.e,15VAC induvidually across the two halves of the secondary winding with opposite polarity, diodes D1 to D2 that rectify the AC appearing across the secondary with D1 and D2 providing D1 and D3 providing full wave rectification to produce a positive output, D2 and D4 providing full wave rectification to produce negative output, capacitors C1 and C2 providing the filtering action C3 to C8 are decoupling capacitor. IC-1 is a fixed output three terminal regulater whereas IC-2 is a fixed output negative three terminal regulator.
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