Amateur Extra E2B: Amateur television
These are the 12 official questions in group E2B of the 2024–2028 Amateur Extra question pool, with the correct answer marked and a plain-English explanation of why it's right. The real exam asks one question from this group.
- E2B01Question 1
In digital television, what does a coding rate of 3/4 mean?
- A25% of the data sent is forward error correction data Correct
- BData compression reduces data rate by 3/4
- C1/4 of the time interval is used as a guard interval
- DThree, four-bit words are used to transmit each pixel
Why: A 3/4 rate means 3 of every 4 bits are data and 1 is error correction: 25%.
- E2B02Question 2
How many horizontal lines make up a fast-scan (NTSC) television frame?
- A30
- B60
- C525 Correct
- D1080
Why: An NTSC frame has 525 lines.
- E2B03Question 3
How is an interlaced scanning pattern generated in a fast-scan (NTSC) television system?
- ABy scanning two fields simultaneously
- BBy scanning each field from bottom-to-top
- CBy scanning lines from left-to-right in one field and right-to-left in the next
- DBy scanning odd-numbered lines in one field and even-numbered lines in the next Correct
Why: Interlacing scans odd lines in one field and even lines in the next.
- E2B04Question 4
How is color information sent in analog SSTV?
- AColor lines are sent sequentially Correct
- BColor information is sent on a 2.8 kHz subcarrier
- CColor is sent in a color burst at the end of each line
- DColor is amplitude modulated on the frequency modulated intensity signal
Why: Analog SSTV sends the color lines one after another.
- E2B05Question 5
Which of the following describes the use of vestigial sideband in analog fast-scan TV transmissions?
- AThe vestigial sideband carries the audio information
- BThe vestigial sideband contains chroma information
- CVestigial sideband reduces the bandwidth while increasing the fidelity of low frequency video components Correct
- DVestigial sideband provides high frequency emphasis to sharpen the picture
Why: Vestigial sideband saves bandwidth while keeping low-frequency video fidelity.
- E2B06Question 6
What is vestigial sideband modulation?
- AAmplitude modulation in which one complete sideband and a portion of the other are transmitted Correct
- BA type of modulation in which one sideband is inverted
- CNarrow-band FM modulation achieved by filtering one sideband from the audio before frequency modulating the carrier
- DSpread spectrum modulation achieved by applying FM modulation following single sideband amplitude modulation
Why: Vestigial sideband is AM with one full sideband and part of the other.
- E2B07Question 7
Which types of modulation are used for amateur television DVB-T signals?
- AFM and FSK
- BQAM and QPSK Correct
- CAM and OOK
- DAll these choices are correct
Why: DVB-T uses QAM and QPSK.
- E2B08Question 8
What technique allows commercial analog TV receivers to be used for fast-scan TV operations on the 70-centimeter band?
- ATransmitting on channels shared with cable TV Correct
- BUsing converted satellite TV dishes
- CTransmitting on the abandoned TV channel 2
- DUsing USB and demodulating the signal with a computer sound card
Why: Transmitting on channels shared with cable TV lets ordinary analog TVs receive 70 cm ATV.
- E2B09Question 9
What kind of receiver can be used to receive and decode SSTV using the Digital Radio Mondiale (DRM) protocol?
- ACDMA
- BAREDN
- CAM
- DSSB Correct
Why: DRM SSTV can be received with an SSB receiver.
- E2B10Question 10
What aspect of an analog slow-scan television signal encodes the brightness of the picture?
- ATone frequency Correct
- BTone amplitude
- CSync amplitude
- DSync frequency
Why: In analog SSTV, tone frequency sets the brightness.
- E2B11Question 11
What is the function of the vertical interval signaling (VIS) code sent as part of an SSTV transmission?
- ATo lock the color burst oscillator in color SSTV images
- BTo identify the SSTV mode being used Correct
- CTo provide vertical synchronization
- DTo identify the call sign of the station transmitting
Why: The VIS code identifies the SSTV mode.
- E2B12Question 12
What signals SSTV receiving software to begin a new picture line?
- ASpecific tone frequencies Correct
- BElapsed time
- CSpecific tone amplitudes
- DA two-tone signal
Why: Specific tone frequencies mark the start of each line.