Скачать или смотреть Raspberry PI CW Morse Code TONE CLONEr - INPUT harsh sounding CW, output PURE SINE WAVE shaped CW

test to send a harsh sounding CW KEYER's sidetone AUDIO OUTPUT over and into the USB SOUND CARD's LINE INPUT of a Raspberry PI 4 and instead of trying to filter out HUM, BUZZ & unwanted CW audio harmonics...
the incoming CPO TONE from the KEYER is only used to trigger a GATE, to send through a sinewave tone that is shaped by the ZAMGATE SIDECHAIN GATE's ATTACK and RELEASE and THRESHOLD controls
https://www.zamaudio.com/?p=976

SETUP:
an incoming CW TONE, (no matter how bad it is, as long as its waveform is stable and accurate in its timing) is converted into a KEYING WAVEFORM for a software CW KEYER setup using ZAMGATE in sidechain mode...
on the upper port of ZAMGATE is a pure sine wave generator that is held back until the incoming tone passes over the ZAMGATE THRESHOLD setting... then it allows the sine wave to pass through, and is wave shaped by ZAMGATE's attack, release controls for rise/fall time desired... zamgate also has a volume control on the sine-shaped cw note that zamgate clones & re-creates form the original tone hitting its SIDECHAIN PORT
a simple post filter, BANDPASS, is used to filter out zamgate's trapezoidal waveshaping ... the BP audio filter 'sands down' the edges that ZAMGATE outputs... to approximate a Raised Cosine edge CW NOTE...

one possible use for this setup, is sending CW over APPs like SONObus...
where you don't want to present a poor sounding CW KEYER's CW AUDIO output TONE to other OPs
https://sonobus.net/

NOTE: the original CW CPO is a TWIN-T sine wave CPO circuit with shaped edges...but still has hum, buzz and harmonics contained in it