Troubleshooting and Diagnostics Flashcards

A technician measures voltage across a resistor and gets 0V, but the source voltage is present. What is the most likely fault?

Answer: The resistor is shorted

A shorted resistor allows all voltage to drop elsewhere, leaving 0V across it.

When using an oscilloscope to troubleshoot, a waveform appears 'clipped' at the top. This most likely indicates:

Answer: Amplifier saturation or clipping

Flat tops on a waveform indicate the amplifier is driven into saturation, clipping the output.

A capacitor in a filter circuit is suspected faulty. Which test best confirms an electrolytic capacitor has dried out?

Answer: ESR (Equivalent Series Resistance) measurement

ESR measurement directly reveals increased internal resistance caused by electrolyte drying.

In a transistor circuit, collector-to-emitter voltage equals the supply voltage. This indicates:

Answer: The transistor is cut off (open)

When VCE equals supply voltage, no current flows through the collector, meaning the transistor is cut off.

A technician finds a circuit board with a burned resistor. After replacing it, the resistor burns again. What should be done next?

Answer: Check the circuit for the root cause of excessive current

A recurring burned resistor indicates an underlying fault causing overcurrent that must be identified and corrected.

When troubleshooting an AM receiver with no audio output but normal AGC voltage, the fault is most likely in:

Answer: The audio amplifier stage

Normal AGC voltage indicates the RF and IF stages are functioning, pointing the fault to the audio section.

A digital multimeter displays 'OL' when measuring resistance. What does this indicate?

Answer: The resistance exceeds the selected range or the component is open

OL (overload) means the reading exceeds the meter's selected range, or the circuit is open.