Amateur ExtraE1A09
Except in some parts of Alaska, what is the maximum power permitted on the 630-meter band?
D
Answer
Extra class rules and station restrictions
Type
A
50 watts PEP (peak envelope power)
B
100 watts PEP (peak envelope power)
C
1 watt EIRP (equivalent isotropic radiated power)
D
5 watts EIRP (equivalent isotropic radiated power)
Answer Notes
The 630-meter band (472 to 479 kHz) is a Medium Frequency (MF) band shared with maritime navigation and other services. To minimize interference to these primary users, the FCC restricts the maximum radiated power an amateur station can produce.
The limit is set to 5 watts EIRP (Equivalent Isotropic Radiated Power). Just like on the 2200-meter band, EIRP measures the effective power radiated by the antenna rather than the transmitter's raw output. Because 630-meter antennas are usually quite inefficient, operators are allowed to use significantly higher transmitter power (PEP) to reach the 5-watt EIRP limit.
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If a station in a message forwarding system inadvertently forwards a message that is in violation of FCC rules, who is primarily accountable for the rules violation?
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If an amateur station is installed aboard a ship or aircraft, what condition must be met before the station is operated?