We want to create an automatic system to measure the bandwidth (-3db band) of a first order circuit. The measurement is carried out through the use of a DAQ card and a GPIB-controlled generator operated by a PC.
The measuring station consists of the following devices:
• PC with Labview
• DAQ board for voltage measurements
• Agilent 33220 A generator to be automatically piloted via GPIB, to generate sinusoidal signals
• An RC circuit (to measure the passband for -3dB)
Technical specifications:
1) Allow the user to set the Start (f start), Stop (f stop) and Step values in frequency and the amplitude of the stimulus signal, making sure that fstart> 10 Hz and fstop <10kHz;
2) Allow the user to set the ratio between sampling frequency and stimulus signal frequency;
3) Allow the user to choose the number of repetitions to be made (N);
4) Display on a graph the Bode diagram of the frequency response (average value on the repetitions N) of the circuit;
5) Give an average value of the band at -3 dB (calculated on the repetitions N) and the corresponding extended uncertainty (with a confidence level of 95%).