This simple split / dual polarity unregulated power supply circuit provides a +15 Volt and -15 Volt supply from a single transformer winding and one full-wave bridge.
A couple of zener diodes in series give you the voltage division and their centerpoint is grounded. (The filter capacitor should not be seated through its case). Since this power supply is unregulated type, so it will not recommended for high quality audio system.
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