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G1E10

COMMISSION'S RULES · - Control categories; repeater regulations; third-party rules; ITU regions; automatically controlled digital station

G1E10§ 97.101G1E →

Why should an amateur operator normally avoid transmitting on 14.100, 18.110, 21.150, 24.930 and 28.200 MHz?

  1. AA system of propagation beacon stations operates on those frequencies
  2. BA system of automatic digital stations operates on those frequencies
  3. CThese frequencies are set aside for emergency operations
  4. DThese frequencies are set aside for bulletins from the FCC
Why Those five frequencies host the NCDXF/IARU International Beacon Project, a worldwide network of beacon stations that transmit in a timed rotation so operators can judge propagation on 20, 17, 15, 12 and 10 meters. Section 97.101 requires amateurs to cooperate and avoid causing interference to other stations, so keeping these slots clear preserves a shared propagation tool for everyone. Notice the pattern: one beacon frequency near the bottom of each of those five HF bands.
Watch out Automatically controlled digital stations do operate in specific band segments, but not on these exact spot frequencies, and the FCC does not broadcast bulletins to amateurs on assigned channels.
One beacon spot per band on 20/17/15/12/10: .100, .110, .150, .930, .200. Listen, don't transmit.
HamSandwich explanation, first draft. The question and answers are the NCVEC text.
47 CFR 97.101 General standards.

(a) In all respects not specifically covered by FCC Rules each amateur station must be operated in accordance with good engineering and good amateur practice.

(b) Each station licensee and each control operator must cooperate in selecting transmitting channels and in making the most effective use of the amateur service frequencies. No frequency will be assigned for the exclusive use of any station.

(c) At all times and on all frequencies, each control operator must give priority to stations providing emergency communications, except to stations transmitting communications for training drills and tests in RACES.

(d) No amateur operator shall willfully or maliciously interfere with or cause interference to any radio communication or signal.

eCFR text as of 1 Sep 2026 · read on ecfr.gov
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The rest of G1E

  1. G1E01 Which of the following would disqualify a third party from participating in sending a message via an amateur …
  2. G1E02 When may a 10-meter repeater retransmit the 2-meter signal from a station that has a Technician class control…
  3. G1E03 What is required to conduct communications with a digital station operating under automatic control outside t…
  4. G1E04 Which of the following conditions require a licensed amateur radio operator to take specific steps to avoid h…
  5. G1E05 What are the restrictions on messages sent to a third party in a country with which there is a Third-Party Ag…
  6. G1E06 The frequency allocations of which ITU region apply to radio amateurs operating in North and South America?
  7. G1E07 In what part of the 2.4 GHz band may an amateur station communicate with non-licensed Wi-Fi stations?
  8. G1E08 What is the maximum PEP output allowed for spread spectrum transmissions?
  9. G1E10 Why should an amateur operator normally avoid transmitting on 14.100, 18.110, 21.150, 24.930 and 28.200 MHz?
  10. G1E11 On what bands may automatically controlled stations transmitting RTTY or data emissions communicate with othe…
  11. G1E12 When may third-party messages be transmitted via remote control?
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