Determining The Connection Sequence Of A Bipolar Transistor - Maker Factory ELECTRONICS EXPERIMENTS BOX Manual

2.3 Determining the connection sequence of a bipolar transistor

Circuit 7: Determining the connection sequence of a PNP transistor
Setup information
Install the transistor as shown in Fig. 2.7 followed by the resistors. Now it is time for the jumpers. For the
purpose of identification, the measurement lines are shown in the figure in black or red. Feel free to use
your own colours. Then connect the moving-coil instrument. Check the placement on the board again and
only then connect the battery.
Experiment
Connect the black line first. Then with the red line touch the remaining two transistor terminals one after
the other. Repeat this until the black line connection is located at the terminal of the other two transistor
connections where the moving-coil instrument measures the greater voltage swing. All other connection
combinations should show a smaller deflection on the meter; if this is not happening, the transistor is
faulty. The black line indicates the base connection of the PNP transistor.
This method works with silicon and germanium transistors, but only for bipolar transistors and not with
FET transistors.
The circuit diagram for this experiment is shown in Chap. 3, Fig. 3.7.
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Components required:
1 x 2N3906 transistor,
1 x 470 Ω resistor, 2 x 1 kΩ
resistors, 2 x 10 kΩ resistor,
1 x moving-coil instrument,
1 x breadboard, 1 x 9V bat-
tery with clip connector
Fig. 2.7: Determining the connec-
tion sequence of a PNP transistor