ISCET Test Equipment Operation & Troubleshooting 3

Question 1

When using a signal generator to inject a test signal into an amplifier, the output is absent. The technician should NEXT:

Accepted Answer

Verify the generator output with an oscilloscope before injecting

Answer

Confirming that the signal generator is actually producing an output before injection prevents misdiagnosis caused by a faulty or misconfigured generator.

Question 2

What measurement does an LCR meter make that a standard DMM cannot?

Accepted Answer

Inductance and capacitance values

Answer

An LCR meter measures inductance (L), capacitance (C), and resistance (R) at specific test frequencies, which is beyond the capability of a standard DMM.

Question 3

A spectrum analyzer shows unexpected sidebands around a carrier frequency. This MOST likely indicates:

Accepted Answer

The carrier is amplitude-modulated or has spurious emissions

Answer

Sidebands symmetrically placed around a carrier are characteristic of modulation or harmonic distortion products.

Question 4

Which setting on a DMM should be used when measuring the forward voltage drop of a diode?

Accepted Answer

Diode test mode

Answer

The diode test mode applies a small forward current and displays the forward voltage drop, providing a definitive diode junction check.

Question 5

When calibrating an oscilloscope probe, a technician observes an over-compensated waveform (peaks on the square wave). The correction is to:

Accepted Answer

Decrease the probe's trimmer capacitance

Answer

Over-compensation (peaks or 'horns' on the square wave) is corrected by decreasing the probe trimmer capacitance until the waveform has flat tops.

(ISCET) International Society of Certified Electronics Technicians Practice Test

(ISCET) International Society of Certified Electronics Technicians Practice Test

ISCET Test Equipment Operation & Troubleshooting 3