Page 111 - Testing Electronic Components

Take a look at the diagram below:

The ac transformer (linear transformer) converts the main line ac voltage
to another lower ac voltage and the lower ac voltage will flow to both the
diodes. The function of the diodes is to convert the ac voltage to DC
voltage and the 1000uf capacitor is use to filter off the ripple in the line.
The clean DC voltage (assuming 7 Volts) is now entering pin 1 of 7805
voltage regulator IC as input voltage. Pin 2 is connected to ground and
pin 3 will be the output which is +5 Volts. The 0.1uf capacitor at the
output line again acts as filter to remove high frequency interference.

Testing Voltage Regulator

Place the red probe to out and you can test the output voltage

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