Amateur ExtraE2D06

Which of the following is a method for establishing EME contacts?

A
Answer
Operating procedures and special operations
Type
A
Time-synchronous transmissions alternating between stations
B
Storing and forwarding digital messages
C
Judging optimum transmission times by monitoring beacons reflected from the moon
D
High-speed CW identification to avoid fading

Answer Notes

EME (Earth-Moon-Earth) or moonbounce communications suffer from extreme path loss and unpredictable fading. Modern EME heavily relies on specialized digital modes, such as JT65, which use precise, time-synchronized intervals (typically one minute long). During an EME contact, stations alternate transmitting and receiving on these fixed, synchronized schedules. This strict timing allows weak-signal decoding software to integrate the received audio over the entire interval, pulling data out of the noise that would otherwise be completely unreadable. Distractors like storing and forwarding, or monitoring beacons, do not represent standard modern EME contact methods. High-speed CW is also incorrect; in fact, weak-signal digital modes rely on slow, structured transmissions to gather enough signal energy over time rather than attempting to outrun the fading with high speed.
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What is the characteristic of the JT65 mode?
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What digital protocol is used by APRS?