Remote CW Keying over the internet of an Elecraft K3S - QRQ CW test - 80 wpm

Using an audio derived cw keying circuit to key CW on the K3S :
- with the circuit attached to the K3S cw keying jack...and being key'ed remotely via a voice chat program called MUMBLE:

a test was recorded where a remote laptop was sending CW audio tones from FLdigi, to the iCW PRO MUMBLE SERVER located in TEXAS...the K3S has its own computer and mumble client - to receive the remote morse code audio tones from the laptop, and convert them into a cw keying signal using one of the circuits mentioned in the link above... this video was just an experiment to see how well the K3S would key qrq cw using this method of remote cw keying over the internet. THE K3S sends back to the remote user the K3S MONITOR SIDETONE audio...the sidetone behavior of the K3S, closely matches its RF OUTPUT behavior, so it is very easy to detect any possible cw keying errors coming out of the K3S, or other things possibly going awry from the setup - by just listening to how your sidetone is sounding...if the sidetone does not sound right , the K3S RF output is going to mimic whatever is going wrong with the sidetone that you might be hearing... ie packet losses, packet delays will make the K3 key "funny"

text sent from FLdigi at 80 wpm was used from W4BQF, TOM's famous COPYING CW OVER 70 WPM article :

using morse code audio tones from the remote user, transmitted to the input of their MUMBLE voice chat voip CLIENT, then being received on RIG's local mumble client/computer, which connects to the K3S RIG via the audio derived cw keying switch circuit

NOTE: all RF OUTPUT of the K3S during this test was going to a 50 OHM DUMMY LOAD

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Comment by Chuck aa0hw on August 19, 2017 at 10:21am

Here is a LIVE recording of an HF 40 METER QSO as an example of using the REMOTE SETUP:

This video demo's a remote laptop station CW keying an Elecraft K3S using paddles, straight key, and a cw keyboard(FLdigi)
- as an example of how it works, a LIVE CW HF QSO on 40 meters has been recorded...

An audio derived cw keying circuit is used to key the K3S remotely:


the K3S has its own LINUX computer and uses MUMBLE VOICE CHAT to receive cw audio tones from the remote laptop...
on the K3S LINUX computer, the Mumble Client sends the receive from laptop's audio to the VLeveL AGC app first, then from the output of VLeveL AGC app, the audio goes to a USB SOUND CARD(with included audio amp) that has an audio cable connecting its audio output to the hardware transformer input of the audio derived cw keying circuit. The circuit rectifies the cw audio tones from the Rig's COMPUTER mumble output, and turns on a transistor that grounds the hot lead of the K3S CW KEYING JACK and thus keys the RIG like normal... the K3S at the same time, in full duplex audio, is sending the HF RECEIVE audio back to the laptop remote station over MUMBLE, using another usb sound card that only uses its LINE INPUT(so there are 2 sounds cards used, one just for transmitting and the other just for receiving...)

NOTE: THE VLeveL Linux app is essential for this method to work well, it functions as an automatic volume(gain) controller so that no matter how much volume of cw audio from the laptop is going to the rig's cw keying circuit, the VLeveL app will keep the audio exactly the same, just like an AGC CIRCUIT, then you can "dial in " how much audio you want going to the circuit, which will allow you to adjust how light or heavy you want your cw keying to sound adjusting the sound card's own volume control...

RealVNC , and GRIG, are used on the remote rig's you can control the frequency of the RIG and a few other of the rig's controls...

NOTE: to key CW using paddles, and st key on the remote laptop station, here is the method used on LINUX:
(a cw keyer keys a 555 chip, with a square wave audio output, that connects to the laptop's mic jack input, from there it is regenerated using TRIGGER MIDI MONO and midiCW):

Comment by Chuck aa0hw on November 4, 2017 at 11:58am

Here is another video demo of a FREE REMOTE RIG setup using a RASPBERRY PI & some free software.  This setup allows for remote operations using morse code, voice, rig control and Log book:

- this video demo's a Raspberry PI 2b, setup for remote rig operations - controlled from a remote LINUX LAPTOP -

A Raspberry PI connects software and hardware to the RIG
3 audio derived RIG CW KEYING circuits are used:
- one to key the CW JACK, one to key the PTT jack and another one to key the CW JACK(for remote's paddles/st key)

software used:
1. FLdigi
2. FLrig
3. FLlog
4. TRX

TRX is an OPUS codec Linux audio streaming CLI app using ALSA

FLdigi, FLrig

here is a list of the TRX audio streams made by TRX for this setup:
1. using the K3S's USB SOUND CARD (playback) TRX is setup to stream the RIG's receiver audio and RIG's sidetone(optional) to the remote HAM RADIO OP's computer's soundcard
2. one TRX RX audio stream is setup to receive the VOICE AUDIO from the remote HAM RADIO OP's MICrophone
3. another TRX RX audio stream(using a different port number) is setup to receive the morse code audio tones from the remote HAM RADIO OP's paddles and straight key

1. TRX is setup to receive the audio stream from the PI, which is forwarding the rig's receiver audio including sidetone(optional)
2. TRX is setup to stream the audio from the paddles and straight key and transit it to the PI(uses the different port number 1351)
3. TRX is setup to stream the audio from the MIC to the PI

NOTE: on the receive streams, you have to experiment with the JITTER BUFFER -j to find the best setting for a stable audio stream...

NOTE: on the transmit streams, if you have a good internet connection, you may be able to lower the latency by lowering the value of the buffer using the -m command(default=16ms)


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