NCTI ROC II BOOK II FINAL Test 1 questions with correct answers

When pressure testing a drop system to check for leakage, What must be done before applying the test signal? Answer The technician must isolate the drop system from the hybrid fiber/coax (HFC) network by disconnecting the drop at the distribution tap. Why do some leakage detection systems utilize a leakage carrier modulated with a tagging signal? Answer To avoid false detection of leaks. When all three sections of a pulse code modulator (PCM) are combined, what function can be performed? Answer · As an analog-to-digital converter (ADC) What prevents the subcarriers in orthogonal frequency division multiplexing (OFDM) from interfering with each other? Answer · The peak power of each subcarrier aligns with the minimum power of the adjacent subcarrier. What two significant signals go into the mixer to create the intermediate frequency (IF)? Answer · The RF signal frequency at the output of the front-end filter and the local oscillator (LO) signal. Which class of amplifier efficiency approaches, but never achieves, 100%? Answer · Class D amplifier. What is the output waveform coming from a ferroresonant power supply? Answer · A quasi-square wave.