Procedure and Tasks

The task of this series of experiment is to build simple but useful circuits.

Start:

        Use your bread board and follow the instructions of the manuscript

        connect the OpAmp μA741, the two voltage sources for V+ and V-.

        define input, output and ground

Voltage divider:

        Build a voltage divider with the resistors R1 and R2 and a 10V battery on the bread board

Inverting amplifier:

        Build a voltage divider with a 10V battery and resistors 100kW and 100W on the same board.

        Use R1=100W, calculate R2 for an amplification of 10 and 100 (since resistor are only available with 2 digit values choose the closest value).

        Amplify the voltage of voltage divider of about 10mV with an output resistance of 100W with the two amplifications.

        What is the output voltage? Take notes for the report.

Non-inverting amplifier:

        Use the same voltage divider

        Use R1=10W, calculate R2 for an amplification of 10 and 100.

        Amplify the same voltage of about 10mV with an output resistance of 100W with the two amplifications.

        What is the output voltage? Take notes for the report.

Ac amplifier:

        Use resistors of 1.8kW and 18kW (100kW) and a capacitor of 0.1μF for the ac-amplifier (amplification of about 10).

        The voltage source is a sinus wave generator with an ac-output of about 1V.

        Build a voltage divider with resistors 10kW and 1MW on the same board for the ac-output (reduction by a factor 100).

        Amplify the voltage of 10mV.

        Register on channel 1 of an oscilloscope the input voltage of 10mV and on channel 2 the output voltage.

        Determine the amplification and the phase relation as a function of frequency at 10, 102, 103, (1,2,4,7,10)x104 Hz

        Repeat the same experiment for an amplification of 100 using 180kW in the ac-amplifier.

        Take notes for the report.

Follower:

        Build a follower.

        With an additional battery of 9V and resistors of 100kW and 1MW build a voltage source of 1V with an output resistance of 100kW. follower.

        Put a load of 100 directly on the output and measure the voltage.

        Use the follower to reduce the output resistance of your voltage source.

Current source:

        Build a current source.

        Use a voltage divider (10V, 10kW, 1MW) for the input voltage and potentiometer of 1kW for the load.

        Measure the current as a function of load resistance.

        Use a voltage divider (10V, 18kW, 1MW) and measure the current as a function of load resistance.

Differentiator:

        Use R=100kW and C=.1mF.

        The voltage Vin is supplied by the sinus wave generator.

        Use a voltage divider with 1kW and 100W.

        With the oscilloscope the input voltage Vin is measured on channel 1 and the differentiated voltage Vout on channel 2.

        Use the frequencies 10, 102, 103, 104, 105 Hz.

        Plot the ratio of Vout /Vin versus the frequency

Rectangular oscillator:

        Use R=10kW and C=.1mF.

        Measure the amplitude and frequency of the output voltage Vout on the oscilloscope.

        Instead of R=10kW use the values 100kW, 1kW.

        Make a table of frequency versus resistance R.

        Calculate the expected frequencies.

Harmonic oscillator:

        Instead of 750W use 405W (1kW and 680W in parallel)

        Use R=1kW and C=.01mF.

        Measure frequency and amplitude.

        Measure the resistance of the lamp (during operation).

        Replace R by 10kW, 100W and repeat the measurement.

        Make table

Integrator:

        Instead of the OpAmp mA741 use LF356.

        Use R=10kW and C=2.2mF.

        Build a voltage divider with a 1kW potentiometer, 1MW and a 10V battery.

        Apply the resulting voltage to the input of the circuit and watch the output voltage with the multimeter as a function of time.

        Adjust the potentiometer so that the maximum output of about 8-10V is reaches after one minute.

        Measure the resistance of the potentiometer.

        Measure and plot Vout as a function of time.

        Register the Vout on the oscillator.

Measurement of the magnetic field of a permanent magnet.

        Make a pickup coil with 20 turns and a known area.

        Place the pickup coil between the poles of the magnet and shorten the capacitor briefly.

        Pull the coil out of the magnet and measure the integrated voltage.

        Calculate the magnetic field.

 


 

Schedule

First day:

        Inverting amplifier with voltage divider

        Non-inverting amplifier with voltage divider

Second day:

        Follower with 1V voltage source (voltage divider)

        Inverting amplifier with follower between voltage divider and amplifier

Third day:

        Ac amplifier

        Current source

Fourth day:

        Measurement of the impedance of an inductor with sinus generator and oscilloscope

Fifth day:

        Differentiator

        Integrator

Sixth day:

        Rectangular oscillator

Seventh day:

        Harmonic oscillator

Eighth day:

        Operational amplifier test