Section-j: mf-hf Equip. And Comms: Key Topic #83: mf-hf Voice and Telex Channel Separation:

83J1 Which statement regarding bandwidth and channel spacing is correct:

A. Bandwidth values are a function of channel spacing values.

B. Channel spacing values are not a function of bandwidth values.

C. Channel spacing values are a function of bandwidth values.

D. Bandwidth & channel values do not vary with emission mode.

83J2 The purpose of ITU channel spacing is:

A. To minimize the number of voice & TELEX channels available.

B. To make most efficient use of the radio spectrum, by using voice channels rather than TELEX channels.

C. To make most efficient use of the radio spectrum, by using TELEX channels rather than voice channels.

D. To minimize the possibility of interference from adjacent channels.

83J3 Which statement regarding channel spacing and bandwidth is true?

A. Both TELEX bandwidth and channel spacing values are less than voice bandwidth and channel spacing values.

B. Voice bandwidth is greater than TELEX bandwidth and therefore voice channel spacing values are less than TELEX channel spacing values.

C. TELEX bandwidth is greater than voice bandwidth and therefore TELEX channel spacing values are less than voice channel spacing values.

D. Both TELEX bandwidth and channel spacing values are greater than voice bandwidth and channel spacing values.

83J4 The proper sequence of channel spacing from narrow to widest is:

A. SSB voice, SITOR (NBDP), VHF-FM voice.

B. SITOR (NBDP), SSB-voice, VHF-FM voice.

C. VHF-FM voice, SITOR (NBDP), SSB-voice.

D. SITOR (NBDP), VHF-FM voice, SSB-voice.

83J5 Communications with an emission of F1B/J2B would typically have a channel spacing of:

A. 0.3 kHz

B. 0.5 kHz

C. 2.8 kHz

D. 3.0 kHz

83J6 Communications with an emission of J3E would typically have a channel spacing of:

A. 0.5 kHz

B. 0.3 kHz

C. 3.0 kHz

D. 2.8 kHz

Answers: 83J1 - C 83J2 - D 83J3 - A 83J4 - B 83J5 - B 83J6 - C

Section-j: mf-hf Equip. And Comms: Key Topic #84: mf-hf Modulation, Bandwidth and Emissions:

84J1 For RF communications, "modulation" is best defined as:

A. Using a single carrier frequency with the proper power level.

B. The combination of information or intelligence on to a radio carrier frequency.

C. Setting up the transceiver with the correct bandwidth to ensure proper communications.

D. The combination of the received frequency and oscillator frequency in the mixer.

84J2 For RF communications, "bandwidth" is best defined as:

A. The modulation technique required to insure proper ITU channel spacing.

B. The emission designation resulting from the desired modulation technique.

C. The portion of the radio spectrum consumed by a particular emission selection and modulation technique.

D. The portion of the radio spectrum reserved for frequency allocations by the ITU.

84J3 In an AM broadcast signal using voice:

A. Varying the amplitude of the carrier and employing both sidebands without the carrier.

B. Varying only the amplitude of the carrier, depending on Double or Single-Sideband operations.

C. Varying the amplitude of the carrier and employing both sidebands and the carrier.

D There is a carrier with constant amplitude and frequency with complex upper and lower sidebands varying in amplitude and frequency.

84J4 In FM communications, the information is applied to the carrier by:

A. Varying the frequency of the carrier to convey the information to other stations.

B. Varying the amplitude or the frequency of the carrier, depending on Double or Single-Sideband operations.

C. Varying only the frequency of the carrier, depending on Double or Single-Sideband operations.

D. Varying the amplitude of the carrier and keeping the frequencies in the sidebands constant.

84J5 The proper sequence of emissions corresponding to the sequence AM-Voice DSB, SSB-Voice without carrier, USB-Voice with carrier and FM-Voice, is:

A. A3E, H3E, J3E, F3E.

B. J3E, H3E, A3E, F3E.

C. H3E, A3E, J3E, F3E.

D. A3E, J3E, H3E, F3E.

84J6 The proper sequence of emissions corresponding to the sequence SSB-Voice without carrier, USB-Voice with carrier, FM-Voice and SITOR (NBDP) TELEX is:

A. J3E, H3E, F3E, F1B.

B. H3E, J3E, F3E, F1B.

C. J3E, H3E, F1B, F3E.

D. H3E, J3E, F1B, F3E.

Answers: 84J1 - B 84J2 - C 84J3 - D 84J4 - A 84J5 - D 84J6 - A