FUN DAMENTALS FOR THE BEGINNER
A kit for these experiments can be purchased from the Nuts & Volts Webstore at
www.nutsvolts.com or call us at 800-783-4624.
Build a DC to DC
This is an excellent circuit that you can use to power projects
that require from zero to something less than nine volts.
1. Build the Circuit.
Using the schematic along with the pictorial diagram, place the
components on a solderless breadboard as shown. Verify that your
wiring is correct.
2. Do the Experiment.
Theory: This circuit is a transistor with a potentiometer in place to
adjust the bias on the base/collector circuit. By adjusting the bias
with the potentiometer, you are able to get an output from zero
volts DC to nine volts DC. The LED across the output lets you know
that there is a voltage. The resistance across transistor Q1 is varied
with the potentiometer. When the resistance across Q1 is high,
there is no voltage at the output. As you lower the resistance across Q1 with the potentiometer, the voltage increases at the output of
the power supply. This is therefore a DC to DC power supply.
Procedure: Connect a nine-volt battery to the battery snap and you should see the LED light up. By using a multimeter at the output,
you should be able to adjust it from zero to nine volts.
by GSSTechEd at
You can order parts
for this experiment
from their website
GK01049 220 ohm resistor
GK01085 6,800 ohm resistor
GK18001 NPN transistor
Nine volt Battery Snap
Four red solid wires
One black solid wire