BNSF Telecom 1 Exam Questions with Correct Answers

BNSF Telecom 1 Exam Questions with Correct Answers VHF - Low and High range Very High Frequency - Answer-Low is 30 to 50 MHz High is 150 to 300 MHz UHF - Ultra High Frequency - Answer-300 MHz - 3 GHz Super High Frequency - SHF - Answer-3-30 GHz Extremely High Frequency - EHF - Answer-30-300 GHz Legacy Band - Answer-25 kHz wide channel Very Narrowband - Answer-6.25 kHz wide, digital Narrowband - Answer-12.5 kHz wide analog What is dB and how much power is it - Answer-dB is a decibel and measures 1/10 of a bell What is an acceptable return loss - Answer--14 dB or better (-15,-16,-17 etc would be worse) 4% or 1.5:1 Return loss formula in dB -6 - Answer-dB=10*log(power out/power in) 25% reflective power or 3:1 Return loss formula in dB -9 - Answer-dB=10*log(power out/power in) 11% reflective power or 2:1 Return loss formula in dB -20 - Answer-dB=10*log(power out/power in) 1% reflective power or 1:22 Return loss formula in dB -30 - Answer-dB=10*log(power out/power in) Less than 1% Tera (T) to Base - Answer-10^12 Giga (G) to Base - Answer-10^9 Mega (M) to Base - Answer-10^6 Kilo (K) to Base - Answer-10^3 Milli (m) to Base - Answer-10^-3 Micro (u) to Base - Answer-10^-6 Convert 44 dBm to Watts - Answer-Watts= 10^((P-30)/10) 25.11 Watts 50 dBm is defined as watts - Answer-100 W 47 dBm is defined as watts - Answer-50 W 30 dBm is defined as watts - Answer-1000 mW or 1 W 33 dBm is defined as watts - Answer-2 W 40 dBm is defined as watts - Answer-10 W 20 dBm is defined as watts - Answer-100 mw 10 dBm is defined as watts - Answer-10 mW 3 dBm is defined as watts - Answer-2 mw 0 dBm is defined as watts - Answer-1 mW How much gain/Loss is 3 dBm - Answer-2X or 1/2 How much gain/Loss is 5 dBm - Answer-3X or 1/3 How much gain/Loss is 6 dBm - Answer-4X or 1/4 How much gain/Loss is 9 dBm - Answer-8X or 1/8 How much gain/Loss is 10 dBm - Answer-10X or 1/10 How much gain/Loss is 20 dBm - Answer-20X or 1/100 How much gain/Loss is 30 dBm - Answer-30X or 1/1000 How much gain/Loss is 40 dBm - Answer-40X or 1/10000 50 Watts to dB - Answer-dBm = 10 * log (1000 * P) 47 dBm Full wave length of 44 MHz (m to in = 39.36) - Answer-6.82 meters or 268.44" 1/2 wave - 134.22" 1/4 wave - 67.11" Full wave length of 160 MHz (m to in = 39.36) - Answer-1.875 meters or 73.81 1/2 wave - 36.9" 1/4 wave - 18.45" Full wave length of 450 MHz (m to in = 39.36) - Answer-.667 meters or 26.25" 1/2 wave - 13.13" 1/4 wave - 6.56" Full wavelength of 900 MHz (m to in = 39.36) - Answer-.333 m or 13.12" 1/2 wave - 6.56" 1/4 wave - 3.28" Full wave length of 2 GHz (m to in = 39.36) - Answer-.15 meters or 5.9" 1/2 wave - 2.95" 1/4 wave - 1.48" Full wave length of 5 GHz (m to in = 39.36) - Answer-.06 meters or 2.36" 1/2 wave - 1.18" 1/4 wave - .59" OSI Model Acronym - Answer-People don't need those stupid packets anyway Layer 1 - Answer-- Physical Layer - Cables, Hubs and Repeaters etc - Cat 5, Twisted Pair protocol - Bits Layer 2 - Answer-- Data Link layer - Two layers : LLC ( Logical Link Control layer) & MAC ( Media Access Control Layer) - Frames - LLC Provides the OS link to the device drivers - MAC Translates generic network request into device specific terms - Frames Layer 3 - Answer-- Network Layer - Routing - Assignment IP address - Packet/ Datagram - Routers & Gateways