Here is the circuit diagram of 9 V
regulator using popular 7809 IC. The
7809 is a 9 Volt voltage regulator IC with
features such as internal current limit,
safe area protection, thermal protection
etc. A 16 V transformer brings down the
230V mains, 1A bridge rectifier rectifies
it and capacitor C1 filters it and 7809
regulates it to produce a steady9V DC
Circuit diagram with Parts list.
1-If a current of 300 mA or above is
required, fit a proper heat sink to the IC
2-If 1A bridge is not available, make one
using four 1N 4007 diodes.