152
2.59 Electronic drum.
Circuit 127:
Electronic drum
Setup information
Install the three transistors, the three, transistors, the eleven resistors, the four ceramic capacitors and the
two electrolytic capacitors as shown in
Fig. 2.127.
The 20 jumper wires come next followed by the jumper,
which will function as a switch (shown dashed). For your guidance, we labelled the “switch” with
Drum.
Last but not least, connect the Piezo element. Check the placement on the board again and only then con-
nect the battery.
You can significantly increase the sensitivity of the Piezo element by using a sound plate or even a sound
box. Read more about it in Chap. 1.2.3
Components required:
2 x 2N3904 transistors,
1 x 2N3906 transistor,
1 x 220
Ω
resistor, 1 x 1 k
Ω
resistor, 1 x 10 k
Ω
resistor,
1 x 22 k
Ω
resistor, 1 x 47 k
Ω
resistor, 2 x 100 k
Ω
resis-
tors, 3 x 220 k
Ω
resistors,
1 x 1 M
Ω
resistor, 3 x 10 nF
ceramic capacitors,
1 x 100 nF ceramic capacitor,
2 x 10 μF electrolytic capaci-
tors, 1 x Piezo element,
1 x breadboard, 1 x 9V bat-
tery with clip connector
Fig. 2.127:
Electronic drum
Experiment
Even if everything is wired correctly, nothing will happen at first. But when you activate the drum button
briefly, you will hear a beat coming from the Piezo element – although unfortunately, a bit low. Volume and
frequency range are reasonable if an audio amplifier is connected to the output of our circuit. But only if
you are familiar with the relevant safety guidelines on working with devices that are to be connected to the
mains as per VDE and know how to observe them should you connect the audio amplifier to the circuit.
The circuit diagram for this experiment is shown in Chap. 3, Fig. 3.127.
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...
