When pressure testing a drop system to check for leakage, What must be done before applying the test signal? - The technician must isolate the drop system
... [Show More] 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? - To avoid false detection of leaks.
When all three sections of a pulse code modulator (PCM) are combined, what function can be performed? - · As an analog-to-digital converter (ADC)
What prevents the subcarriers in orthogonal frequency division multiplexing (OFDM) from interfering with each other? - · 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)? - · 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%? - · Class D amplifier.
What is the output waveform coming from a ferroresonant power supply? - · A quasi-square wave.
What instrument should be used to accurately measure the output voltage of a ferroresonant power supply? - · A true root mean square (RMS) digital multimeter (DMM)
What could a light dimmer with a silicon controlled rectifier (SCR) create in a customer premises? - · Radio frequency interference (RFI).
What is a characteristic of a bipolar junction transistor (BJT) common emitter configuration? - · The output signal is taken from the emitter.
What is done to an operational amplifier (op amp) to create a low-pass filter circuit? - · A capacitor is placed in parallel with the feedback resistor that is connected to the op amp inverting input (-).
What is the core objective of the Data Over Cable Service Interface Specification (DOCSIS) Provisioning of Ethernet passive optical network (EPON), or DPOE, access architecture? - · To make the EPON elements appear and operate as DOCSIS elements to the existing DOCSIS-based back office provisioning operations.
What benefit does a power-doubling configuration offer compared to a single cascade push-pull hybrid amplifier? - · Twice the output with the same distortion.
Which statement characterizes a distributed powering system? - · Uses multiple locations for power supply placement within the outside plant
What is done to an operational amplifier (op amp) to create a low-pass filter circuit? - · The number of inductors plus capacitances that are in a filter circuit
What is required for checking the physical network integrity when maintaining the coaxial cable network? - · Being observant and performing some minor tasks while engaged in regularly scheduled activities.
Which type of map contains node information? - · Design map.
Why is the term "gain control" applied to amplifier gain and controls inaccurate? - · The only way to vary the output of any amplifier is to adjust the amplitude level of the signal going into the amplifier.
When activating a fiber-optic network, which acceptance testing stage includes adjusting attenuation levels for the first time? - · During equipment activation.
What is the thermal noise level used for reference in broadband cable noise calculations? - · -59.2 dBmV.
Which component of a digital optical network is used to receive digital modulation light waves and convert them to an electrical signal? - · Optical transponder.
Why is sweeping an amplifier during alignment more accurate than rough balancing? - · Rough balanced amplifiers have large gaps of unobserved spectrum that could have frequency response related issues.
When used together, which two optical amplifiers achieve very wide optical gain with a flattened bandwidth for better, overall network performance? - · Erbium-doped fiber amplifier (EDFA) and Raman amplifiers:
Why is a sweepless sweep impractical for sweeping the upstream? - · The short-duration upstream channels that originate from various sources prevents a normalized reference trace from being stored.
What type of fiber-to-the-x (FTTx) topology does a passive optical network (PON) use to make a point-to-multipoint (P2MP) fiber-optic cable connection between the broadband cable headend and the customer premises? - · Fiber-to-the-home (FTTH). [Show Less]