Learn/ Extra course/Module 9 of 10
Extra Course, Module 9: Operating at the Frontier
Covers NCVEC 2024-2028 Extra Pool, Subelement E2 (Operating Procedures). Five questions on your exam come from this material.
Ray hands you a printed satellite schedule, a contest calendar, and a moonrise table. "Extra operating is the stuff with procedures attached: linear transponders, television, pileups, moonbounce, and the machine modes at their limits. None of it is harder than what you already do. All of it has customs, and tonight you learn the last of them."
9.1Satellites, the Full Manual
The Technician course flew FM satellites; the Extra pool flies the linear birds.
Orbital vocabulary: an ascending pass travels south to north. Keplerian elements remain the parameters defining the orbit. A geostationary satellite appears fixed in one position in the sky, the always-available bird that changed amateur satellite work. And a satellite's mode designates its uplink and downlink frequency bands, the letters specifying frequency ranges: L band and S band are the 23- and 13-centimeter bands, extending the U/V vocabulary upward.
The linear transponder is the heart of the serious birds: it relays a whole band segment at once, and it accepts SSB, CW, FM, SSTV, PSK, and packet alike. All of these; a linear transponder does not care what rides through it. The inverting variety processes the uplink by mixing it with a local oscillator and transmitting the difference product, with three consequences that all appear as one "all of these" answer: the band segment comes out reversed, USB becomes LSB, and Doppler shift is reduced because uplink and downlink shifts run in opposite directions and partially cancel.
Etiquette, quantified from the Technician course: uplink ERP must be limited on a linear transponder because the transponder's total downlink power is shared: your excess uplink reduces the downlink power available to every other user. The beacon comparison from your first course was this rule's field method.
Hardware craft: a circularly polarized antenna minimizes both spin modulation and Faraday rotation, Module 2's EME answer doing double duty for satellites. And the digital store-and-forward function holds digital messages in the satellite for later download, the orbiting mailbox that serves stations that never share a footprint.
Knowledge Check 9.1
Tap an answer. In your own words first, then check yourself.
1. What happens to a USB uplink through an inverting linear transponder?
2. Why must uplink ERP be limited on a linear transponder?
3. What do "L band" and "S band" designate?
E2A the easy way: all 12 questions, with the right answer
Every pool question in this group. Read the answer, let the tip make it stick.
E2A01 What is the direction of an ascending pass for an amateur satellite?
Answer From south to north
Tip An ascending pass climbs up the globe, so the bird is heading from south to north as it rises.
E2A02 Which of the following is characteristic of an inverting linear transponder?
Answer All these choices are correct
Tip An inverting transponder flips sideband, flips the passband, and reverses Doppler drift, so all those traits hold true.
E2A03 How is an upload signal processed by an inverting linear transponder?
Answer The signal is mixed with a local oscillator signal and the difference product is transmitted
Tip Inverting means mix with a local oscillator and send the difference, which is why your sideband gets flipped.
E2A04 What is meant by the “mode” of an amateur radio satellite?
Answer The satellite’s uplink and downlink frequency bands
Tip A satellite's mode is just its uplink and downlink band pairing, nothing to do with the voice or data format.
E2A05 What do the letters in a satellite’s mode designator specify?
Answer The uplink and downlink frequency ranges
Tip Each letter in the mode designator tags a frequency range, one for the uplink and one for the downlink.
E2A06 What are Keplerian elements?
Answer Parameters that define the orbit of a satellite
Tip Keplerian elements are the numbers that pin down an orbit, so tracking software can predict where the bird will be.
E2A07 Which of the following types of signals can be relayed through a linear transponder?
Answer All these choices are correct
Tip A linear transponder is content agnostic, so CW, SSB, and data all ride through it equally well.
E2A08 Why should effective radiated power (ERP) be limited to a satellite that uses a linear transponder?
Answer To avoid reducing the downlink power to all other users
Tip The transponder shares a fixed power budget, so hogging it with high ERP starves everyone else's downlink.
E2A09 What do the terms “L band” and “S band” specify?
Answer The 23- and 13-centimeter bands
Tip L band is the 23 cm band and S band is the 13 cm band, the two higher microwave satellite bands.
E2A10 What type of satellite appears to stay in one position in the sky?
Answer Geostationary
Tip A geostationary bird orbits at the same rate Earth turns, so it seems parked in one spot overhead.
E2A11 What type of antenna can be used to minimize the effects of spin modulation and Faraday rotation?
Answer A circularly polarized antenna
Tip Circular polarization keeps signal steady through tumbling and Faraday rotation because it does not care about the twist.
E2A12 What is the purpose of digital store-and-forward functions on an amateur radio satellite?
Answer To hold digital messages in the satellite for later download
Tip Store-and-forward lets the satellite stash your digital message and hand it down on a later pass.
9.2Pictures Through the Air
Amateur television, both speeds:
Fast-scan (analog NTSC): a frame contains 525 horizontal lines, painted as an interlaced pattern: odd-numbered lines in one field, even-numbered lines in the next, halving flicker without doubling bandwidth. The bandwidth diet that makes a 6 MHz TV channel possible at all is vestigial sideband: amplitude modulation transmitting one complete sideband and only a portion of the other, which reduces bandwidth while preserving the fidelity of low-frequency video components, the parts of the picture that need both sidebands most. The practical 70-centimeter trick: fast-scan ATV transmits on frequencies shared with cable TV channels, so an ordinary analog cable receiver becomes an ATV monitor.
Digital ATV speaks broadcast: DVB-T uses QAM and QPSK modulation (Module 6's constellations, employed), and its coding rate states the FEC budget: a rate of 3/4 means one quarter of the transmitted data is forward error correction. Redundancy as a line item.
Slow-scan trades motion for bandwidth, fitting pictures into a voice channel:
- Brightness is encoded as tone frequency: higher tone, brighter pixel, the image literally sung.
- Color is sent as sequential lines, red, green, and blue scans of each line in turn.
- Specific tone frequencies signal the start of each new picture line, and the VIS code at the transmission's head identifies the SSTV mode in use, so the software knows how to decode what follows.
- Digital SSTV using the DRM protocol is received on an ordinary SSB receiver, the sound card doing the rest.
Knowledge Check 9.2
Tap an answer. In your own words first, then check yourself.
1. What does a DVB-T coding rate of 3/4 mean?
2. How does analog SSTV encode brightness?
3. What is vestigial sideband modulation?
E2B the easy way: all 12 questions, with the right answer
Every pool question in this group. Read the answer, let the tip make it stick.
E2B01 In digital television, what does a coding rate of 3/4 mean?
Answer 25% of the data sent is forward error correction data
Tip A 3/4 coding rate means three of every four bits are payload, so the other 25 percent is error correction.
E2B02 How many horizontal lines make up a fast-scan (NTSC) television frame?
Answer 525
Tip Standard NTSC fast-scan TV paints a full frame in 525 horizontal lines.
E2B03 How is an interlaced scanning pattern generated in a fast-scan (NTSC) television system?
Answer By scanning odd-numbered lines in one field and even-numbered lines in the next
Tip Interlace splits a frame into two fields, odd lines first then even lines, woven together for a smoother picture.
E2B04 How is color information sent in analog SSTV?
Answer Color lines are sent sequentially
Tip Analog SSTV sends the color channels one after another, line by line, rather than all at once.
E2B05 Which of the following describes the use of vestigial sideband in analog fast-scan TV transmissions?
Answer Vestigial sideband reduces the bandwidth while increasing the fidelity of low frequency video components
Tip Vestigial sideband trims one sideband down to save bandwidth while keeping low-frequency video detail crisp.
E2B06 What is vestigial sideband modulation?
Answer Amplitude modulation in which one complete sideband and a portion of the other are transmitted
Tip Vestigial sideband is AM with one full sideband plus just a stub of the other.
E2B07 Which types of modulation are used for amateur television DVB-T signals?
Answer QAM and QPSK
Tip Amateur DVB-T digital TV rides on QAM and QPSK carriers.
E2B08 What technique allows commercial analog TV receivers to be used for fast-scan TV operations on the 70-centimeter band?
Answer Transmitting on channels shared with cable TV
Tip Running fast-scan TV on cable-shared 70 cm channels lets an ordinary analog TV tune it right in.
E2B09 What kind of receiver can be used to receive and decode SSTV using the Digital Radio Mondiale (DRM) protocol?
Answer SSB
Tip DRM-encoded SSTV rides in a voice-width slot, so an SSB receiver is what you need to grab it.
E2B10 What aspect of an analog slow-scan television signal encodes the brightness of the picture?
Answer Tone frequency
Tip In analog SSTV, the audio tone frequency maps to pixel brightness, so higher tone means brighter.
E2B11 What is the function of the vertical interval signaling (VIS) code sent as part of an SSTV transmission?
Answer To identify the SSTV mode being used
Tip The VIS code at the start of an SSTV frame tells the receiver which SSTV mode is coming.
E2B12 What signals SSTV receiving software to begin a new picture line?
Answer Specific tone frequencies
Tip Specific sync tones tell the SSTV software when one picture line ends and the next begins.
9.3Contests, DX, and the Remote Station
The competitive arts, formalized:
- Identification in a pileup: send your full call sign, once or twice. The partial-call habit wastes everyone's time and the pool says so directly.
- Why DX stations work split (transmit and receive on different frequencies): it separates the callers from the DX station, improves efficiency, and accommodates callers who cannot transmit on the DX station's frequency. All of these; split is not affectation, it is traffic engineering. The dual-VFO control from General Module 8 was built for this moment.
- Where and where not: VHF/UHF contest activity concentrates in the weak-signal segment near the calling frequency, and contesting is excluded from 30 meters by band-plan custom, the quiet band from your General course staying quiet even on contest weekends.
- Paperwork with formats: contest logs are submitted in Cabrillo format; general log data is exchanged as ADIF (the format your General capstone already used); confirmations flow through Logbook of The World, which accepts US-to-US, international, and award-credit contacts alike. All of these. A DX QSL Manager handles the receiving and sending of confirmations on a DX station's behalf, the administrative Elmer of the DX world.
- The remote station, resolved: operating a US station remotely, with the transmitter in the US, requires no additional identifier. And the physics of remote operation gets its word: latency, the delay between a control operator's action and the corresponding change in the transmitted signal, the reason remote CW takes practice.
- Mesh networking, completed: amateur mesh networks run on frequencies shared with unlicensed wireless data services, built from wireless routers running custom firmware, the Technician course's modified-firmware fact now paired with its spectrum.
Knowledge Check 9.3
Tap an answer. In your own words first, then check yourself.
1. How should you identify when calling a DX station in a pileup?
2. What is the Cabrillo format?
3. What is latency in remote operation?
E2C the easy way: all 12 questions, with the right answer
Every pool question in this group. Read the answer, let the tip make it stick.
E2C01 What indicator is required to be used by US-licensed operators when operating a station via remote control and the remote transmitter is located in the US?
Answer No additional indicator is required
Tip Remote control from inside the US needs no extra indicator, since the transmitter is on home soil.
E2C02 Which of the following file formats is used for exchanging amateur radio log data?
Answer ADIF
Tip ADIF is the common text format hams use to swap log data between programs.
E2C03 From which of the following bands is amateur radio contesting generally excluded?
Answer 30 meters
Tip The 30 meter band is a shared WARC band reserved for casual work, so contesting stays off it.
E2C04 Which of the following frequencies can be used for amateur radio mesh networks?
Answer Frequencies shared with various unlicensed wireless data services
Tip Ham mesh networks run on bands shared with unlicensed Wi-Fi style data gear, like parts of 2.4 GHz.
E2C05 What is the function of a DX QSL Manager?
Answer Handle the receiving and sending of confirmations for a DX station
Tip A DX QSL manager takes over sending and receiving confirmations on behalf of a busy DX station.
E2C06 During a VHF/UHF contest, in which band segment would you expect to find the highest level of SSB or CW activity?
Answer In the weak signal segment of the band, with most of the activity near the calling frequency
Tip On VHF/UHF contests the SSB and CW crowd gathers in the weak-signal segment near the calling frequency.
E2C07 What is the Cabrillo format?
Answer A standard for submission of electronic contest logs
Tip Cabrillo is the standard file format for turning in your electronic contest log.
E2C08 Which of the following contacts may be confirmed through the Logbook of The World (LoTW)?
Answer All these choices are correct
Tip LoTW confirms contacts across bands and modes, so all those contact types qualify.
E2C09 What type of equipment is commonly used to implement an amateur radio mesh network?
Answer A wireless router running custom firmware
Tip A ham mesh node is usually just a consumer wireless router reflashed with custom firmware.
E2C10 Why do DX stations often transmit and receive on different frequencies?
Answer All these choices are correct
Tip DX stations split transmit and receive for several good reasons at once, so all those apply.
E2C11 How should you generally identify your station when attempting to contact a DX station during a contest or in a pileup?
Answer Send your full call sign once or twice
Tip In a pileup, send your whole call once or twice, no partials, so the DX can log you cleanly.
E2C12 What indicates the delay between a control operator action and the corresponding change in the transmitted signal?
Answer Latency
Tip Latency is the lag between your control action and the signal actually changing on the air.
9.4Bouncing Signals Off the Sky
The VHF/UHF digital frontier, where Module 2's exotic paths get their operating procedures:
- Meteor scatter runs on MSK144, the WSJT-X mode built for split-second trail reflections. EME runs on Q65, and the pool distinguishes it from its ancestor precisely: Q65 averages multiple receive cycles, accumulating a signal too weak for any single period, which is how amateurs with modest arrays now work the Moon. JT65, the ancestor, contributed the family traits: multitone AFSK modulation decoding at very low signal-to-noise ratios.
- The EME contact method is the family discipline: time-synchronous transmissions alternating between stations, each station owning fixed periods, the FT8 rhythm from your General course stretched to fit a two-and-a-half-second lunar echo.
- In VHF contests using FT8 or FT4, the exchange replaces the signal report with the grid square, the Technician course's grid locator now serving as contest currency.
- APRS completes its arc with protocol detail: it rides AX.25 packet, transmitting its beacons as Unnumbered Information frames (fire-and-forget, no connection), relayed by digipeaters. The path WIDE3-1 decodes as three digipeater hops requested, one remaining, the packet's travel budget written in its header. And APRS remains the technology for real-time tracking of balloons carrying amateur transmitters, Module 1's balloon rules now with their tracking layer.
Knowledge Check 9.4
Tap an answer. In your own words first, then check yourself.
1. Which mode is designed for meteor scatter?
2. How does Q65 pull EME signals out of the noise?
3. What does the APRS path WIDE3-1 request?
E2D the easy way: all 11 questions, with the right answer
Every pool question in this group. Read the answer, let the tip make it stick.
E2D01 Which of the following digital modes is designed for meteor scatter communications?
Answer MSK144
Tip MSK144 is built for the quick bursts of meteor scatter, packing a message into a fleeting ion trail.
E2D02 What information replaces signal-to-noise ratio when using the FT8 or FT4 modes in a VHF contest?
Answer Grid square
Tip In FT8 and FT4 VHF contesting, your grid square stands in for the signal report.
E2D03 Which of the following digital modes is designed for EME communications?
Answer Q65
Tip Q65 is the go-to weak-signal mode for bouncing signals off the Moon on EME.
E2D04 What technology is used for real-time tracking of balloons carrying amateur radio transmitters?
Answer APRS
Tip APRS carries the GPS position of a balloon payload for live tracking as it drifts.
E2D05 What is the characteristic of the JT65 mode?
Answer Decodes signals with a very low signal-to-noise ratio
Tip JT65 shines by pulling messages out of noise at very low signal-to-noise ratios.
E2D06 Which of the following is a method for establishing EME contacts?
Answer Time-synchronous transmissions alternating between stations
Tip EME works by both stations trading timed transmit periods, so each one listens while the other sends.
E2D07 What digital protocol is used by APRS?
Answer AX.25
Tip APRS packets ride on the AX.25 protocol underneath.
E2D08 What type of packet frame is used to transmit APRS beacon data?
Answer Unnumbered Information
Tip APRS beacons go out as Unnumbered Information frames, fire-and-forget with no acknowledgment.
E2D09 What type of modulation is used by JT65?
Answer Multitone AFSK
Tip JT65 uses multitone AFSK, stepping among many closely spaced tones to carry its data.
E2D10 What does the packet path WIDE3-1 designate?
Answer Three digipeater hops are requested with one remaining
Tip WIDE3-1 asked for three digipeater hops and one hop still remains to be used.
E2D11 How do APRS stations relay data?
Answer By packet digipeaters
Tip APRS spreads its data outward through packet digipeaters that repeat each beacon.
9.5HF Digital at the Limits
The HF machine modes, specified to Extra depth:
- Data emissions below 30 MHz use FSK, and the direct variety modulates the transmitter's VFO itself, versus audio FSK's tones through the SSB chain, the General course's RTTY distinction now stated as architecture.
- The WSJT-X family tree: transmit/receive timing is synchronized by computer clocks (the whole family's shared metronome); FT8's cycle is 15 seconds; FT4's name decodes as four-tone continuous-phase frequency shift keying; and FST4 is the flexible sibling: four-tone Gaussian FSK, variable transmit/receive periods, multiple tone spacings. All of these. Longer periods buy deeper decodes, the Q65 averaging principle available on HF.
- The taxonomy questions: WSPR does not support keyboard-to-keyboard operation (it is a beacon, full stop, from General Module 6); PSK31 uses variable-length character coding (the Varicode from General); PACTOR transfers binary files where the keyboard modes cannot; FT8 has the narrowest bandwidth of the common contenders; and under clear conditions PACTOR IV delivers the highest data throughput. Every mode is a point on the same curve: bandwidth and time traded against data and depth.
- The last machine standing is ALE, automatic link establishment: ALE stations constantly scan a list of frequencies, activating the radio when their call sign arrives on any of them. It is Module 2's propagation problem solved by brute diligence, the radio finding its own open band, and it is how interoperable HF networks stay connected across the day without a human tuning anything.
Knowledge Check 9.5
Tap an answer. In your own words first, then check yourself.
1. How do WSJT-X stations stay synchronized?
2. Which mode cannot be used keyboard-to-keyboard?
3. How does an ALE station establish contact?
E2E the easy way: all 13 questions, with the right answer
Every pool question in this group. Read the answer, let the tip make it stick.
E2E01 Which of the following types of modulation is used for data emissions below 30 MHz?
Answer FSK
Tip Below 30 MHz, data emissions lean on FSK, shifting the carrier between tones to send bits.
E2E02 Which of the following synchronizes WSJT-X digital mode transmit/receive timing?
Answer Synchronization of computer clocks
Tip WSJT-X leans on your computer clock being accurate, since the modes key off synchronized timing.
E2E03 To what does the "4" in FT4 refer?
Answer Four-tone continuous-phase frequency shift keying
Tip The 4 in FT4 marks its four-tone continuous-phase FSK keying.
E2E04 Which of the following is characteristic of the FST4 mode?
Answer All these choices are correct
Tip FST4 covers a wide range of timing and purposes, so all those characteristics describe it.
E2E05 Which of these digital modes does not support keyboard-to-keyboard operation?
Answer WSPR
Tip WSPR is a beacon-and-report mode only, so it has no live keyboard-to-keyboard chatting.
E2E06 What is the length of an FT8 transmission cycle?
Answer 15 seconds
Tip One FT8 transmit-receive cycle runs 15 seconds, quartering each minute.
E2E07 How does Q65 differ from JT65?
Answer Multiple receive cycles are averaged
Tip Q65 improves on JT65 by averaging several receive cycles to dig deeper into the noise.
E2E08 Which of the following HF digital modes can be used to transfer binary files?
Answer PACTOR
Tip PACTOR is the HF data mode built to move binary files reliably with error correction.
E2E09 Which of the following HF digital modes uses variable-length character coding?
Answer PSK31
Tip PSK31 uses varicode, giving common letters short codes so text flows faster.
E2E10 Which of these digital modes has the narrowest bandwidth?
Answer FT8
Tip Among these modes FT8 squeezes into the narrowest bandwidth, only about 50 Hz.
E2E11 What is the difference between direct FSK and audio FSK?
Answer Direct FSK modulates the transmitter VFO
Tip Direct FSK shifts the transmitter's own VFO, while audio FSK feeds tones into an SSB input.
E2E12 How do ALE stations establish contact?
Answer ALE constantly scans a list of frequencies, activating the radio when the designated call sign is received
Tip ALE keeps scanning a frequency list and wakes the radio when it hears its assigned call sign.
E2E13 Which of these digital modes has the highest data throughput under clear communication conditions?
Answer PACTOR IV
Tip Under clean conditions PACTOR IV delivers the fastest data throughput of these modes.
Review: every Exam Anchor from this module
E2A Ascending pass: south to north. Keplerian elements: orbit parameters. Geostationary: fixed position in the sky. Mode letters: uplink and downlink frequency ranges; L and S bands are 23 and 13 cm. Linear transponders relay SSB, CW, FM, SSTV, PSK, packet (all). Inverting transponder: LO mixing, difference product out; band reversed, sidebands inverted, Doppler reduced (all). Limit uplink ERP: excess robs downlink power from other users. Circular polarization: counters spin modulation and Faraday rotation. Store-and-forward: holds messages for later download.
E2B NTSC: 525 lines; interlace: odd lines one field, even the next. Vestigial sideband: one full sideband plus part of the other; preserves low-frequency video fidelity at reduced bandwidth. 70 cm ATV: shares cable TV channel frequencies. DVB-T: QAM and QPSK; coding rate 3/4 = 25 percent FEC. SSTV: brightness as tone frequency; color as sequential lines; new lines signaled by specific tones; VIS code identifies the mode; DRM SSTV needs only an SSB receiver.
E2C Pileup ID: full call, once or twice. DX split: separates callers, improves efficiency, accommodates privilege differences (all). VHF contest activity: weak-signal segment near the calling frequency. Contesting excluded from 30 meters. Cabrillo: contest log submission. ADIF: log exchange. LoTW: confirms all contact types (all). QSL Manager: handles a DX station's confirmations. US remote transmitter: no added indicator. Latency: control-to-transmission delay. Mesh: unlicensed-shared frequencies, custom-firmware routers.
E2D MSK144: meteor scatter. Q65: EME, averaging multiple receive cycles. JT65: multitone AFSK, very low SNR decoding. EME method: time-synchronous alternating transmissions. FT8/FT4 VHF contests: grid square replaces the report. APRS: AX.25 protocol, Unnumbered Information frames, digipeater relay; WIDE3-1 = three hops requested, one remaining; APRS tracks amateur balloons.
E2E Sub-30 MHz data: FSK; direct FSK modulates the VFO. WSJT-X timing: computer clock synchronization. FT8: 15-second cycles. FT4: four-tone continuous-phase FSK. FST4: Gaussian four-tone, variable periods, multiple spacings (all). WSPR: not keyboard-to-keyboard. PSK31: variable-length coding. PACTOR: binary file transfer; PACTOR IV: highest clear-channel throughput. FT8: narrowest of the common modes. ALE: scans a frequency list, activating on its call sign.
Before you move on
The schedule, the calendar, and the moonrise table are now operating documents: you can work an inverting transponder without confusing yourself, send a picture by tone, run a pileup by the customs, request three digipeater hops in one header, and schedule a moonbounce attempt by perigee and Q65 period. The frontier is procedural, and you have the procedures.
One module remains, one exam question, and one send-off. It is about the same thing it was at the end of your first course.
© 2026 Anthony Pelfanio, K4DIA. All rights reserved.