the typical modern RIG, usually shapes its CW TRANSMIT waveform as a raised cosine edged cw note with a Rise and Fall time between 5 and 10 milliseconds....For this test a 7ms rise and fall time of a perfect raised cosine cw note created by FLdigi is used to represent the "modern rigs" and tested against another software CW KEYER called the ZamGate CW KEYER. https://youtu.be/zO6oFOZ5lVA
The ZamGate CW Keyer has its own HP-LP filter included to filter out all of the edge noise and thus prevents harmonic spurs from being transmitted out on the air... the typical edge noise that gets generated on most every rig's cw notes...
NOTE: even with a very large rise and fall time such as 7ms, the leading edge noise rise time harmonic spurs are significant, and will be transmitted along with the main CW NOTE's pitch. This edge noise gets louder the faster the CW SPEED becomes...the edge noise can get so loud at the higher QRQ CW speeds, that the CW EDGE generated noise is almost as loud as the actual CW TONE you are trying to copy...
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