Element 5 New.pdf

ELEMENT V – Signals, Frequencies and Emission A sine wave was measured to have a 20 Volt peak measurement. What is the peak-to-peak voltage that can be measured from this wave? A. 40 Volts B. 20 Volts C. 10 Volts D. 14.14 Volts From the choices listed, what emission type do Amateur Radio Operators in the 430 MHz band commonly use to communicate locally with using voice communications or telephony? A. QPSK B. FSK C. CW D. FM How many symbols does the binary numbering system have? A. 2 B. 10 C. 16 D. 32 Most television signals employ vestigial sideband transmission __________ A. to conserve bandwidth B. allow low frequency content such as screen brightness and scanning synchronizing pulses C. both A and B D. none of the above What is the approximate length of a half-wave dipole antenna for 28.495 MHz? A. 10.52 meters B. 2.63 meters C. 5.26 meters D. 28.495 meters What is the device that converts digital signal into audible tones suitable for voice grade channel transmission and reception? A. Modem B. Telephone C. Microphone D. Speaker MODEM is short for __________ A. Mode Modulator B. Modulator/Demodulator C. Modulator/Demultiplexer D. none of the above

Key clicks in CW reception is caused by __________ A. Poor quality morse key or paddle B. Over-driving the final amplifier C. Instantaneous transmission of full carrier power D. none of the above What is the harmonic frequency of a signal having 14.28751 meters wavelength? A. 7095 kHz B. 21010 kHz C. 42000 kHz D. 14005 kHz What is commonly known as RTTY can be _________ A. F1B and F2B B. C3F C. A1A D. F3E Which of the following is an effect of over-modulation? A. Excessive bandwidth B. Insufficient audio C. Insufficient bandwidth D. Frequency drift The best method in suppressing the carrier and unwanted sideband is filtering with __________ A. LC filter B. Crystal filter C. Mechanical filter D. both B and C “CQ 40m CQ 40m” was and is still heard on radio. The band is mentioned in the call because __________ A. in the early days of radio, there was poor suppression of harmonics that sometimes a person can copy the harmonic on a higher band and think it is the actual transmission B. It sounds clearer C. it is required by law D. it is the international practice If you have an amplitude modulated signal and feed it into a filter to remove the carrier and any signals below the carrier frequency you get will get a __________ A. FM signal B. lower sideband signal C. upper sideband signal D. pulsed signal

In the early days of radio, an audio amplifier’s output was fed into the plate circuit of a CW RF power amplifier and this essentially became an __________ A. FM transmitter B. AM transmitter C. single sideband transmitter D. CW transmitter The difference between A3E and J3E is __________ A. the latter’s carrier is suppressed B. the latter has double sidebands C. the former has one sideband only D. the former has a single sideband The difference between FSK and AFSK is __________ A. none B. first one uses a modulated subcarrier while the other does not C. the former is asynchronous D. you cannot generate an AFSK outside the radio What is the term used for the multiple of a fundamental frequency? A. Harmonic Frequency B. Multiple Frequency C. High Frequency D. Medium Frequency A1 emission is __________ A. aural telegraphy B. generally employs morse code C. composed of unmodulated continuous wave (CW) signals D. all of the above What is the approximate length of a Marconi antenna for 228 MHz? A. 1 meter B. 0.33 meter C. 2 meters D. 0.5 meter What is the fundamental frequency of a signal if the 2nd harmonic is at 56 MHz? A. 28 MHz B. 56 MHz C. 112 MHz D. none of the above For satellite and space communications, the ideal wave polarization is __________ A. vertical B. horizontal C. circular D. none of the above

When a double balanced mixer is injected with an RF carrier and an audio signal, it normally yields A. double sideband with carrier B. double sideband with no carrier C. upper sideband with carrier D. lower sideband with carrier Signal to noise ratio (SNR) is __________ A. ratio of amplitude of signal voltage over amplitude of noise voltage B. ratio of noise power over signal power C. the ratio of signal voltage over power voltage D. none of the above While frequency drift is the unintended offset of an oscillator from the nominal frequency, what is the maximum instantaneous difference between the modulated frequency and the nominal carrier frequency? A. frequency shift B. frequency deviation C. frequency change D. frequency variability In the emission designation, F3E, the number 3 denotes __________. A. bandwidth of the modulating signal B. type of channel in this case one channel C. frequency modulation D. none of the above Which transmission has the narrowest bandwidth? A. A3E B. A3J C. F3E D. A1A From the choices listed, what emission type do Amateur Radio Operators in the 144MHz band commonly use to communicate locally with using voice communications or telephony? A. QPSK B. FSK C. CW D. FM An electromagnetic field can be plotted graphically on the __________ axis. A. X and Y axis of a graph B. X, Y, Z axis of a graph C. Y and Z axis of a graph D. none of the above

For a sinusoidal signal measuring 2 volts peak to peak, what is the root mean square value? A. 1 volt RMS B. 3 volts RMS C. 0.707 volt RMS D. none of the above The VCO, voltage controlled oscillator, is used often in VHF and UHF radios because injecting audio signals will __________. A. frequency modulate it B. amplitude modulate it C. pulse modulate it D. all of the above What is the approximate length of a full-wave loop antenna for 21.005 MHz? A. 21 meters B. 3.57 meters C. 7.14 meters D. none of the above 300,000,000 meters per second is the speed of light in __________. A. air B. water C. vacuum D. none of the above How many symbols does the decimal numbering system have? A. 2 B. 10 C. 16 D. 32 What is the frequency of a signal having a wavelength of 10.6 meters? A. 3.8 MHz B. 28.3 MHz C. 29.3 MHz D. 21.295 MHz What emission type do Amateur Radio Operators in the HF band commonly use to communicate with each other using voice communications or telephony? A. Continuous Wave B. Frequency Shift Keying C. Single Side Band D. RTTY The positive peak of a wave signal is also known as “__________”. A. Floor B. Crest C. Trough D. Apex

To improve harmonic suppression in a transmitter, this is employed at the amplifier’s output. A. low pass filter B. crystal filter C. high pass filter D. reflective filter How many symbols does the hexadecimal system have? A. 2 B. 10 C. 16 D. 32 To reduce key clicks, the best technique is to ___________. A. introduce a slow rise of carrier power at the start of each transmitted wave B. prevent overdrive of the final amplifier C. ensure a good SWR at the antenna D. slow down the words per minute sent What is the wavelength of the frequency 435 MHz? A. 7 meters B. 0.7 meter C. 21.1342 meters D. 25.88 meters A sine wave with a peak voltage of 5 Volts has been measured. What is the RMS value of this wave? A. 5 Volts B. 10 Volts C. 2.5 Volts D. 3.535 Volts What emission type do Amateur Radio Operators in the HF band commonly use to communicate with each other using telegraphy or Morse code? A. Continuous Wave B. Frequency Shift Keying C. Single Side Band D. RTTY A dBi unit specification in antennas denotes the antenna gain reference to the __________. A. Isotropic radiator B. Isopole radiator C. Marconi radiator D. Dipole radiator A sine wave with a peak-to-peak voltage of 20 Volts has been measured. What is the RMS value of this sine wave? A. 10 Volts B. 7.07 Volts C. 20 Volts D. 5 Volts

What is the frequency of a signal having a wavelength of 0.25 meters? A. 3.8 MHz B. 28.3 MHz C. 1.2 GHz D. 25.88 meters What is the wavelength of the frequency 1800 kHz? A. 166.67 meters B. 180 meters C. 180 centimeters D. 25.88 meters What is the wavelength of a signal whose central carrier is monitored at 14.195 MHz? A. 7 meters B. 0.7 meter C. 21.1342 meters D. 25.88 meters The negative peak of the wave signal is also known as “__________” A. Floor B. Crest C. Trough D. Apex Which is a VHF amateur band allocation? A. 70 cm B. 23 cm C. 6-meter band D. 10-meter band