34
2.4 Determining the current amplification of a bipolar transistor
Circuit 9:
PNP transistor B test
Setup information
Install the transistor as shown in
Fig. 2.9
. Install all other resistors. Now it is time for the jumpers. Connect
the moving-coil instrument. Check the placement on the board again and only then connect the battery.
Components required:
1 x 2N3906 transistor,
1 x 1 M
Ω
resistor, 1 x 220
Ω
resistor, 1 x 100
Ω
resistor,
1 x moving-coil instrument,
1 x breadboard, 1 x 9V bat-
tery with clip connector
Fig. 2.9:
PNP transistor B test
Experiment
If everything is wired correctly, the moving-coil instrument will show a strong deflection. The deflection
shows the transistor’s current amplification factor B. Full scale means B = 500. In our present case the
circuit can be used to determine the current amplification factor of any low power PNP silicon bipolar tran-
sistor. The simple design of the moving-coil instrument however, sets limits to its accuracy.
The circuit diagram for this experiment is shown in Chap. 3, Fig. 3.9.
Summary of Contents for ELECTRONICS EXPERIMENTS BOX
Page 4: ......
Page 265: ...267 Fig 3 56 Cir cuit 56 Audio limiter Fig 3 57 Circuit 57 Amplifier for a storm detector...
Page 269: ...271 Fig 3 64 Circuit 64 Stabilizer for 1 9 V Fig 3 65 Circuit 65 Stabilizer for 2 5 V...
Page 275: ...277 Fig 3 80 Circuit 80 Quiztimer 30 seconds Fig 3 81 Circuit 81 Handy diode tester...
Page 315: ...317 Fig 3 179 Circuit 179 HF generator 150 kHz Fig 3 180 Circuit 180 HF generator 420 kHz...
