Ham Amateur Radio Technician Practice Exam 2025 – The Complete All-in-One Guide to Exam Success

The output waveform of an unfiltered full-wave rectifier connected to a resistive load consists of a series of DC pulses that occur at a frequency that is twice the frequency of the AC input. In a full-wave rectifier, both halves of the AC waveform are utilized, resulting in the rectification of the input sine wave into a series of positive voltage peaks.

When the AC input waveform goes positive and negative, the full-wave rectifier inverts the negative half so that both halves contribute to the output. This creates a pulsating DC waveform, where the frequency of the output pulses is double that of the input AC waveform. For example, if the input AC frequency is 60 Hz, the output will have a frequency of 120 Hz.

Without filtering, the output remains in this pulsed form—characterized by gaps between the peaks—rather than transitioning to a steady DC level. This is pivotal because it highlights the distinction between filtered and unfiltered outputs; filtering would smooth out these pulses into a more constant voltage, but since it's specified that the rectifier is unfiltered, the output is indeed a series of pulses.