Theory of operation:

Reproducing CW timing through the Internet has always been difficult because of the unreliable packet delivery of the Internet. The RemoteTx audio system, though, delivers audio precisely. This can be used to send audio CW tones from a PC to a remote radio (via RemoteTx RPi) and generate reliable CW transmissions. At the remote radio/RPi, a USB sound card that has VOX triggering is used to key the CW key jack.

The approach is as follows:

• AT REMOTE PC:
  A CW keyer that emits CW audio is plugged into a PC sound card that is set as the default microphone of the RemoteTx audio connection.
  (Ham-Gadgets Pico Keyer is a good option)
• AT RADIO STATION WITH RemoteTx RPI:
  A Ham-Interfaces or SignaLink USB Audio device with VOX triggering circuit is used to trigger the radio’s key input. When a CW tone is received from the remote PC, the VOX PTT is triggered which is fed into the radio CW key input which in turn keys the radio. The radio key setting is set to straight key.
  The radio phones jack is also connected to the VOX USB sound card line in, so that RX CW can be heard on the remote PC.

 

 

 

List of Materials:

HamGadgets KEYER FOR REMOTE PC:
https://hamgadgets.com/UPK-Ultra-Pico-Keyer-Built_p_31.html

VOX / PTT CIRCUIT FOR RADIO:
https://www.ham-interfaces.com/product-page/digimode-3-micro-yaesu-built-in-usb-sound-card-and-vox-ptt

CW AUDIO TONE GENERATOR FOR REMOTE PC SIDETONE (OPTIONAL):
https://www.gigaparts.com/cw-morse-scout-cpo-morse-code-straight-key-practice-oscillator.html

SOUND CARD FOR REMOTE PC:
https://www.amazon.com/dp/B00IRVQ0F8/

3.5 MM SPLITTER:
https://www.amazon.com/gp/product/B00LM0ZGK6/

3.5 MM PIGTAILS:
https://www.amazon.com/gp/product/B07Y8KGJKL/

MINI SPEAKER FOR REMOTE PC SIDETONE:
https://www.amazon.com/gp/product/B007OYAVLI/

MINI DIN 6 PIN FEMAIL SOCKETS:
https://www.amazon.com/gp/product/B0C6KVSWVF/