98
Circuit 73:
RC low pass 3 kHz
Setup information
Install the transistor and the electrolytic capacitor as shown in
Fig. 2.73
. Last but not least, connect the
Piezo element. Check the placement on the board again.
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:
1 x 47 k
Ω
resistor,
1 x 1 μF electrolytic
capacitor, 1 x Piezo ele-
ment, 1 x breadboard
Fig. 2.73:
RC low pass 3 kHz
Experiment
We will use electrical filter circuits, among other things, to suppress the noise. The basic circuit that serves
this purpose is a RC or LC filter consisting of a resistor/inductor and a capacitor. Depending on the wiring,
this creates a low pass or a high pass. In our case, we are using an RC low pass filter; the cutoff frequency,
up to which signals can pass, is 3 kHz If you have an mp3 player connected to the input, it will sound as if
the music comes from a handset.
The circuit diagram for this experiment is shown in Chap. 3, Fig. 3.73.
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...
