Extra exam question E1D02
Subelement E1, COMMISSION RULES· Group E1D · 47 CFR §97.211(b)
Which of the following may transmit encrypted messages?
- A.Telecommand signals to terrestrial repeaters
- B.Telecommand signals from a space telecommand station (correct answer)
- C.Auxiliary relay links carrying repeater audio
- D.Mesh network backbone nodes
WhyTelecommand signals transmitted from a space telecommand station to a satellite are the one type of amateur transmission permitted to be encrypted. §97.211(b) carves out a specific exception to the amateur service's usual ban on codes and ciphers meant to obscure meaning, allowing encrypted control signals sent from a space telecommand station to a satellite, since securing the uplink prevents an unauthorized party from seizing control of the spacecraft, answer B. Ordinary telecommand to a terrestrial repeater, relayed repeater audio, and mesh network traffic all still fall under the general prohibition on obscuring a message's meaning.
Published 2026-08-28 · Last updated 2026-08-28 · Question text is verbatim from the 2024-2028 NCVEC Element 4 pool (public domain); the explanation above is original writing, see our methodology.
Related questions
- E1D01What is the definition of telemetry?
- E1D03What is a space telecommand station?
- E1D04Which of the following is required in the identification transmissions from a balloon-borne telemetry station?
- E1D05What must be posted at the location of a station being operated by telecommand on or within 50 kilometers of the Earth’s surface?
- E1D06What is the maximum permitted transmitter output power when operating a model craft by telecommand?