30-06-2012, 02:16 PM
To plot the frequency response of constant-k band reject filter
To plot the frequency response of constant-k band reject filter..docx (Size: 22.55 KB / Downloads: 31)
THEORY:
A band reject filter is one which passes all frequencies below a lower cut-off frequency fc1 and above an upper cut-off frequency fc2 and attenuates the rest of frequencies. A band stop filter in its simplest form is a tandem of a low pass filter with a high pass filter as shown in fig. below:
PROCEDURE:
1. Connect sine wave generator at the input of the filter. Adjust sine wave amplitude to 5Volt p-p. Keep the input voltage constant throughout the experiment.
2. Connect CRO at the output of the filter.
3. Vary the input frequency from minimum to 10KHz in proper steps in sine wave generator and every time note the input frequency and corresponding output voltage from the CRO in the observation table.
4. Plot the graph between input frequency & Output Voltage taking input frequency (in Hz) on x-axis and output voltage (in Volts) on y- axis on semi log graph paper.
5. Calculate the cut-off frequencies from the formula as well as from the graph.