From Electronics I Laboratory Manual

Attenuators
Many times we are faced with the problem of needing a particular voltage for an application but the signal generator (or any other source) will not produce the desired voltage level.  To solve this dilemma normally we could use a voltage attenuator using two resistors.  The exact value of the resistors is not important because the level of the voltage can be adjusted using the signal generator amplitude control and the ratio of the two resistors.

                                                                                                                                                   
Note:

When using the signal generator to apply a voltage to an energized circuit, a capacitor must be placed between the signal generator and the circuit to block the circuit voltage from affecting the signal generator.

                                                                                                                                                   

Figure No. 1.1 shows an attenuator.  The voltage across R2 (V2) could be applied to a circuit.  This can be made to be of any value between the source voltage (Eg) and zero1.

By applying the voltage divider rule to this circuit we obtain


               (1.1)

Eq. 1.1 is the attenuated voltage of the source (Eg in this case).  Notice that by choosing appropriate values for R1 and...


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