Build your own FREE SDR Receiver APP for Morse Code QSO audio outputs on iCW: Mumble/Discord/Sonobus

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Chuck Vaughn

Jul 29, 2022, 9:19:50 AM7/29/22
to iCW - internet CW

SDR RECEIVER built from RECRI KEYER's SDR MODULES: several common CW Transmit/RX issues show up on iCW 1. keyclicks/square wave on OP's signal 2. CW pitch/keying too soft on OP's signal 3. OP sending at low bitrate 4. unwanted audio harmonics on OP's signal by using the SDR setup shown on this video, you can listen to everyone sending CW at the [ PITCH/volume/rise/fall time/bandwidth of CW audio ] that you want to listen to....
no matter the condition of the CW SIDETONE that the other OP is sending... basic setup pathway mumble output goes to an AGC/Limiter app - X42 DPL the AGC/Limiter will keep the volume at the same level, no matter what volume the other OP is sending at...
which is very important to be able to set the THRESHOLD SETTING of sidechain mode: a RECRI KEYER i/Q oscillator is being help back by ZAMGATE from passing through ZAMGATEs upper ports while ZAMGATE is in sidechain mode... however, when the output of the X42 AGC/Limiter hits the sidechain port of zamgate, it "keys" the RECRI i/Q oscillator to pass through Zamgate's upper port to go into the recri sdr filter module...
where you can adjust how HARD/SOFT you want to copy CW at.... after the FILTER, it goes to a RECRI SDR L0-MIXER where you can dial in the exact CW PITCH you want to listen to your CW at...
similar to adjusting the RIT on your RIG... and no matter what frequency you choose on the LO-MIXER, the characteristics of the BANDPASS FILTER's effect... remain the same ...
bandwidth/ Q / center FREQ of the bandpass filter etc.. the CW audio bandpass filter therefore effectively TRACKS exactly with the LO-MIXER frequency setting,
keeping whatever settings you placed onto the bandpass stay in place no matter where the LO-MIXER has adjusted the final CW PITCH output

S. Steltzer

Jul 29, 2022, 12:57:45 PM7/29/22
to 'joe living' via iCW - internet CW
That is certainly amazing.

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