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ATT TEST 13 ACTUAL TEST 2025 | ALL QUESTIONS
AND CORRECT ANSWERS | GRADED A+ | VERIFIED
ANSWERS | LATEST TEST (JUST RELEASED)
When the carrier is modulated, where is the information located? --------- CORRECT ANSWER-----------------Upper and lower sidebands of composite signal What is the difference frequency known as? ---------CORRECT ANSWER--- --------------Intermediate Frequency What is the receivers ability to faithfully reproduce a desired signal is based on what two things? ---------CORRECT ANSWER-----------------Its sensitivity and selectivity What does Phase Lock Loop do? ---------CORRECT ANSWER----------------- Compares output of VCO with a reference frequency What happens if the output of VCO is different than the reference frequency? ---------CORRECT ANSWER-----------------DC controlling voltage is generated to steer VCO to correct output What frequency range do AM broadcasts use? ---------CORRECT ANSWER----------------- 535 - 1605 kHz
What are two types of AM receiver tuning? ---------CORRECT ANSWER----- ------------Synthesized and manual What are two types of synthesized tuning? ---------CORRECT ANSWER----- ------------Direct and indirect synthesis What are 4 components of PLL? ---------CORRECT ANSWER----------------- Phase detector, loop filter, VCO, and frequency counter/divider What are 3 benefits of synthesized tuning? ---------CORRECT ANSWER---- -------------Greater freq stability, freq changed electronically, reduced cost, smaller size What type of tuning incorporates PLL and VCO to provide desired frequency? ---------CORRECT ANSWER-----------------Indirect synthesis What is amplitude modulation? ---------CORRECT ANSWER----------------- Information is encoded into carrier wave by varying RF carriers amplitude and maintaining constant frequency AM IF signal is at what frequency? ---------CORRECT ANSWER--------------- --455 kHz FM IF signal is at what frequency? ---------CORRECT ANSWER--------------- --10 MHz
What type of SSB has two sidebands that can each carry completely different intelligence? - --------CORRECT ANSWER-----------------ISB What is the purpose of balanced modulator? ---------CORRECT ANSWER-- ---------------Eliminates/suppresses carrier What is the heart of sideband generation? ---------CORRECT ANSWER----- ------------Balanced modulator What are 3 methods for SSB generation? ---------CORRECT ANSWER------ -----------Filter method, phase method, Third/Weaver method What is a unique aspect of SSB? ---------CORRECT ANSWER----------------- Must recreate carrier in order for intel to be detected What frequency range is used by CB? ---------CORRECT ANSWER----------- ------26.965-27.405 MHz What is heterodyning? ---------CORRECT ANSWER-----------------Combining 2 frequencies to convert to new frequency without altering intel in original SSB is not _____ dependent ---------CORRECT ANSWER----------------- Phase
What are two types of AGC? ---------CORRECT ANSWER----------------- Carrier and Audio derived What is the bandwidth of HF? ---------CORRECT ANSWER----------------- 3MHz to 30MHz What is the purpose of the HF system? ---------CORRECT ANSWER--------- --------Allows long range high frequency surface to surface, surface to air, air to air, air to surface, two way comms and data comms at LOS and over horizon What are 4 modes of operation of HF system? ---------CORRECT ANSWER-----------------AM, AME, USB, LSB What is the most common HF mode of operation? ---------CORRECT ANSWER-----------------USB What type of HF causes large bandwidth and large power consumption? --- ------CORRECT ANSWER-----------------AM What type of HF has the carrier reinserted prior to transmission? --------- CORRECT ANSWER-----------------AME
FM guard bands are _____ kHz at upper and lower boundary of each channel and guard against interference ---------CORRECT ANSWER--------- --------24kHz What are two types of FM generation? ---------CORRECT ANSWER---------- -------Direct (capacitor) and indirect (phase modulation) What are the primary advantages of FM? ---------CORRECT ANSWER------- ----------Greater noise suppression, high fidelity (stereo) reception, less interference (limits capture effect), reduced transmitter power to cover assigned area What are two types of phase detectors? ---------CORRECT ANSWER-------- ---------Sequential (digital) and Multiplier (no memory) What is the a general rule of thumb regarding the sun and frequency? ------- --CORRECT ANSWER-----------------The higher the sun the higher the frequency FM has a carrier and a _____ number of sidebands ---------CORRECT ANSWER-----------------Infinite FM sidebands have _____ amplitudes and are always an _____ distance from center (carrier) frequency ---------CORRECT ANSWER----------------- equal amplitude, equal distance from carrier
What is the bandwidth of narrow band FM? ---------CORRECT ANSWER---- -------------10 to 30 kHz Why is NBFM reduced bandwidth? ---------CORRECT ANSWER--------------- --To accommodate signal/voice transmissions What is primary advantage of NBFM? ---------CORRECT ANSWER----------- ------RF spectrum conservation What are four steps of TS NBFM? ---------CORRECT ANSWER----------------
- Assess, troubleshoot, repair, re-assess What frequency are NBFM guard bands? ---------CORRECT ANSWER------ -----------Two 5kHz guard bands Shorts usually also cause what? ---------CORRECT ANSWER----------------- Opens What are diodes susceptible to? ---------CORRECT ANSWER----------------- Heat
