Turtleand Energy

Rung 6 · See change over time

Let one AC half-cycle through

Use one diode to turn a reversing AC waveform into pulsing one-direction output.

foundation25 minutes0 of 4 stages explored
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A ten volt peak alternating source feeding a diode and one kiloohm load in series.
10 volt peak AC source -> diode -> 1 kiloohm load -> return

Knowledge this exercise builds on

Lesson 5: DC vs AC

Practice loop

Try each step before revealing its answer.

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ComponentsSee the parts and values before you start.
  • One 10 V peak, 50 Hz AC voltage source
  • One diode
  • One 1 kΩ load resistor
  • Input and output scopes
PredictCommit to an expected result before running the circuit.

Draw the expected source waveform and load waveform. Decide what happens during the half-cycle that reverse-biases the diode.

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The diode conducts during one half-cycle and blocks the other. The load sees pulses of one polarity, reduced slightly by the diode’s forward voltage. During the blocked half-cycle, load current is approximately zero.

BuildWire the circuit yourself from a blank canvas.

Place the diode in series between the AC source and load. Keep the diode orientation unchanged for the first run.

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Use one series path:

AC source -> diode -> 1 kΩ load -> source return

Place one scope across the source and another across the load. Reversing only the diode should reverse which half-cycle reaches the load.

MeasureSee what to inspect, compare, and change.

Compare the source and load scopes. Record the output during both source polarities, then reverse the diode and repeat.

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With the first orientation, one half-cycle appears across the load and the reverse half-cycle stays near zero. Reversing the diode passes the opposite half-cycle. The conducting pulse is slightly smaller than the source because of the diode’s forward drop.

ExplainConnect the observation back to your model.

Explain why this output is pulsing DC rather than steady DC.

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The diode is a direction-sensitive path. It blocks one half-cycle and conducts during the other, so the load current no longer reverses.

The direction is fixed, which makes the output DC, but its magnitude still rises and falls to zero, which makes it pulsing rather than steady.

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Safety boundary

This is a low-voltage educational model.

Do not translate it into mains construction, household wiring, battery-pack work, or real protection settings. Real electrical systems need rated components, proper protection, test equipment, and qualified safety judgment.