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Speech processors can be very useful when operating SSB. The purpose of a speech processor as used in a modern transceiver is to increase the intelligibility of transmitted phone signals during poor conditions. (G4D01) It increases average power of a transmitted single sideband phone signal. (G4D02)
Of course, you must adjust it properly to gain these benefits. All of these choices are correct when considering the effects of an incorrectly adjusted speech processor (G4D03):
- Distorted speech
- Splatter
- Excessive background pickup
Most commercial receivers have an S meter. An S meter is found in a receiver. (G4D06) An S meter measures received signal strength. (G4D04)
The S meter uses a logarithmic scale, with an increase of one S unit being equivalent to a gain of 6 dB. So, to change the S- meter reading on a distant receiver from S8 to S9, you would have to raise the power output of your transmitter approximately 4 times. (G4D07) Assuming a properly calibrated S meter, an S meter reading of 20 dB over S-9 is 100 times stronger compared to an S-9 signal. (G4D05)
When operating near band edges, it’s important to know the frequency range that your signal will actually occupy so that your transmissions stay within the amateur band. When operating in LSB mode, your signal actually occupies a 3 kHz space below the displayed carrier frequency. When the displayed carrier frequency is set to 7.178 MHz, a 3 kHz LSB signal occupies 7.175 to 7.178 MHz. (G4D08)
When operating in the 40 meter General Class phone segment when using 3 kHz wide LSB, your displayed carrier frequency should be at least 3 kHz above the edge of the segment. (G4D10) That is to say that you should not set your radio to a frequency less than 7.178 MHz so that your transmitted signal stays withing the General Class portion of the band.
Similarly, when operating USB, your signal occupies a space starting at the displayed carrier frequency and extending up 3 kHz. With the displayed carrier frequency set to 14.347 MHz, a 3 kHz USB signal occupies 14.347 to 14.350 MHz. (G4D09) When operating in the 20 meter General Class band, your displayed carrier frequency should be no closer than 3 kHz below the edge of the band when using 3 kHz wide USB. (G4D11)
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