Iron-Free Push-Pull Amplifier - Maker Factory ELECTRONICS EXPERIMENTS BOX Manual

2.51 Iron-free push-pull amplifier

Circuit 114: Iron-free push-pull amplifier
Setup information
Install the three transistors, the two diodes, the four resistors and the two electrolytic capacitors as shown
in Fig. 2.114 Followed by the 14 jumper wires. Last but not least, connect the Piezo element. Check the
placement on the board again and only then connect the battery. You can significantly increase the sensitiv-
ity of the Piezo element by using a sound plate or even a sound box. Read more about it in Chap. 1.2.3
Experiment
If you connect an mp3 player to the input, you will hear the playback loud and sound coming from the
Piezo element.
The circuit diagram for this experiment is shown in Chap. 3, Fig. 3.114.
Components required:
2 x 2N3904 transistors,
1 x 2N3906 transistor,
2 x 1N4148 silicon diodes,
1 x 100 Ω resistor,
1 x 1 kΩ resistor,
1 x 100 kΩ resistor,
1 x 220 kΩ resistor,
2 x 1 nF ceramic capaci-
tor, 2 x 10 μF electrolytic
capacitors, 1 x Piezo
element, 1 x breadboard,
1 x 9V battery with clip
connector
Fig. 2.114: Iron-free push-pull
amplifier
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