Amateur ExtraE1A04
May an Extra class operator answer the CQ of a station on 3.601 MHz LSB phone?
C
Answer
Extra class rules and station restrictions
Type
A
Yes, the entire signal will be inside the SSB allocation for Extra class operators
B
Yes, the displayed frequency is within the 75-meter phone band segment
C
No, the sideband components will extend beyond the edge of the phone band segment
D
No, US stations are not permitted to use phone emissions below 3.610 MHz
Answer Notes
The Extra class phone segment on the 75/80-meter band begins at 3.600 MHz. For any transmission to be legal, the entire emission bandwidth must be contained within the authorized phone segment.
In Lower Sideband (LSB) operation, the signal bandwidth extends downward from the carrier frequency by approximately 3 kHz. If the carrier is set to 3.601 MHz, the actual transmitted signal will extend down to 3.598 MHz.
Because 3.598 MHz is below the 3.600 MHz boundary, the sideband components cross into the CW/data segment. Operating phone in the CW/data segment is illegal for all US amateurs, so you may not answer the CQ.
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What is the highest legal carrier frequency on the 20-meter band for transmitting a 2.8 kHz wide USB data signal?
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Who must be in physical control of the station apparatus of an amateur station aboard any vessel or craft that is documented or registered in the United States?