Ham Radio General Class Practice Test

Which of the following is a typical use for an operational amplifier?

1. Phase shift oscillator

2. Comparators

3. Voltage follower

4. All of the above

The correct answer is: All of the above

An operational amplifier (op-amp) is a versatile component widely used in various electronic circuits due to its ability to amplify voltage signals and perform mathematical operations like addition, subtraction, integration, and differentiation. In the context of the choices provided, an operational amplifier can indeed be used in all of the applications listed. A phase shift oscillator uses op-amps to create a specific phase shift in the feedback loop, allowing it to generate oscillating signals. This application typically involves configuring the op-amp in a manner that produces a sinusoidal output. Comparators are another essential application of operational amplifiers. In this configuration, the op-amp compares two input voltages and outputs a signal indicating which input is higher. This is critical in implementing various control systems and signal processing tasks. A voltage follower, or buffer, is a configuration where the op-amp provides a high input impedance and low output impedance. This ensures that the voltage of the input signal is preserved while preventing any loading effects on the signal source. Given the versatility of operational amplifiers in these different configurations, all the listed applications exemplify typical uses for op-amps, justifying the choice of "all of the above" as the correct answer.