Spectrum Field Tech Questions with Answers 2023

Current/ amperage - Flow or movement of electric charges Resistor - a passive two-terminal material that impedes the flow of current What is the most common workplace hazard involving electricity? - Electrical shocks What is minimum approach distance? - The shortest safe distance to keep from energized conductors CATV at the pole - 40'' CATV at the mid-span - 24'' CATV at the house - 12'' Live parts of electric equipment must be guarded against at how many volts? - 50 volts What are the 2 kinds of grounds required by Safety standards for electrical systems? - Service and Equipment What are circuit protection devices designed to do? - Automatically limit or shift off the flow of electricity in the event of a ground fault, overload, or short circuit in the wiring system OSHA - Occupational Safety and Health Administration CATV - Community Antenna Television HFC - Hybrid Fiber Coax What are the four sources of signals? - Satellite, local origination, off air, fiber optics Forward - 54 MHz-1 GHz G.B. - Guard Band Return - 5-42 MHz Downstream (forward path) - Forward signal from the headend to a customer Upstream (reverse path) - Return signal from a customer to the headend Signal frequency - Number of times that an RF signal completes a cycle from a positive value to a negative value and back in one second Ultrasonic frequencies are higher than what? - Audio Infrasonic frequencies are below what? - Audio How many hertz can the human ear hear? - 20-20,000 Per NTSC requirements, what is a tv channels bandwidth? - 6MHz FCC (Federal Communications Commission) - Gov agency responsible or regulating and assigning frequencies throughout the US HFC distributes what? - Broadband signals through a network of various elements Nodes - Convert the light signals from the headend into radio frequency signals for delivery to customer Ingress signal leakage TV: - Lines in picture, ghosting, pay per view problems, scrambling problems Ingress signal leakage Internet: - Lack of internet access, lack of internet access, lack of email services, data problems Ingress signal leakage Voice - Telephone call failures (incoming and out coming) QAM (quadrature amplitude modulation) - Is both an analog and digital modulation scheme used for transmitting digital data as an analog signal by using a carrier split into 2 carriers of identical frequency phase shifted 90 degrees apart How many programming channels can digital signals have within a 6 MHz space? - 12 CLI - Cumulative Leakage Index What are charters technical standard for 256 QAM and OFDM carries at CPE? - 34 dB or better BER - bit error rate Post BER - 1.0e-9 Pre BER - 1.0e-6