Raspberry PI 4 as a remote RIG over ip AFCW mode CW RIG keying interface - network stability test

[Chuck aa0hw]

sending a TEXT FILE at 60 wpm, from the REMOTE OP's PC, to a RASPBERRY PI 4 that is using the RIG's internal USB SOUND CARD as its own sound card....this test uses an RTSP SERVER:CLIENT audio over ip setup... the CW AUDIO you hear during this test is from the PI 4's TRANSMIT AUDIO MONITOR feed - going back to the REMOTE OP to get the PTT to activate before the CW TONE arrives, a 5555 hz ptt tone is used at a low volume, just enough to activate the PTT vox circuit of the RIG(ELECRAFT K3S) NOTE: the k3s has a brick wall low pass filter cutoff at 4Khz ..so none of the 5555 tone gets transmitted the CW TONE is delayed by 19 milliseconds...just enough to allow the PTT tone to fully activate the rig's ptt VOX CIRCUIT so that when the CW TONE arrives, none of the CW elements get chopped off on their first bits, which happens if you use the CW TONE to activate the rig's vox ptt a text file was sent from the AD5DZ CW keyer and its associated cw keying apps https://github.com/recri/keyer Gstreamer was used as the audio over ip RTSP SERVER::CLIENT audio streams from and to the RIG::pi4 interface and the remote op's desktop the text file was fully sent and received without any noticeable audio glitches..the spectrum purity of the CW NOTE that will be transmitted by the RIG's LINE INPUT on LSB, is very pure without any significant harmonics above or below the CW PITCH...which is very important for sending cw in AFCW MODE the next network test would be to find out how low in latency can the RTSP SERVER::client can run without any packet drops or buffer issues on the PI or the remote OP's PC etc plus the network performance of the LAN's ROUTERS and SWITCHES and ETHERNET CABLES etc... ultimately, AVB networking would offer one of the best solutions to getting near zero delay for remote rig operations...however, the cost of the consumer hardware is prohibitive for now...LINUX is working on some AVB solutions using the intel NIC CARD that supports AVB https://www.presonus.com/learn/technical-articles/an-introduction-t... https://forums.presonus.com/viewtopic.php?f=233&t=11088 https://www.intel.com/content/www/us/en/products/docs/network-io/et... https://www.amazon.com/Intel-I210-T1-Network-Adapter-E0X95AA/dp/B00... https://tsn.readthedocs.io/avb.html http://avnu.github.io/OpenAvnu/