Wow Keith, what a lengthy explanation. Thanks for your time! I'm going to read this story carefully this weekend.
Appreciated the help! 73, Evert PA2KW / 5T2KW / W8S -----Original Message----- From: Keith Trinity WE6R <[email protected]> Sent: Friday, 5 December 2025 17:08 To: [email protected] Cc: [email protected] Subject: Re: [Elecraft] K3 : PTT-KEY setting That is the default behavior, you can change it, it is in the manual errata / addendum; https://ftp.elecraft.com/K3S/Manuals%20Downloads/E740258E%20K3S%20Owner's%20man%20errata%20A1-2.pdf PTT/KEY USE WITH THE USB PORT IMPROVED: Some PC applications can control PTT and KEY at the K3S via the RTS/DTR signals of the USB port. However, use of these signals may also allow the PC’s USB port initialization to unexpectedly activate transmit at the K3S. This can happen if the computer is turned on after the K3S, or if the USB cable is not connected. There is now a "Safe" mode (the default) which disables PTT-KEY transmit until the K3S receives a command via USB, such as a read of the rig's VFO frequency. To turn on safe mode on/off, go into CONFIG:PTT-KEY and tap '1' to select "USB SAFE" or "UNSAFE". Exit the menu and turn the K3S off/on. Applications that use PTT KEY via USB but never send commands may require "UNSAFE" mode. In this case, unwanted transmit can be avoided by turning the PC on before the K3S. More info from N6TV; Inadvertent keying transmit unwanted TX Com Port keys radio PTT-KEY N6TV red LED. Fix; Set your PTT KEY to OFF OFF, Or continue reading; To prevent Windows reboots and USB cable connections from accidentally keying a K3S at boot time, I strongly recommend changing the Properties of all FTDI virtual serial ports, including those provided by the K3S or by the Elecraft KUSB cable or equivalent FTDI USB-to-Serial adapter. The Windows default options are not good for FTDI devices, because the options "encourage" Windows to look for a serial mouse (!) or a dial-up modem (!) on the virtual serial port port at boot time, or whenever the USB cable is reconnected. Those actions pulse the DTR and RTS pins about 7 times. To prevent this unwanted behavior, always uncheck the box next to Serial Enumerator and always check the box next to Disable Modem Ctrl At Startup so it looks like this: And MORE: More info re RTS DTR and PTT KEY, radio not keying via USB KIO3B, transmitting on digital modes, N6TV PTT via RTS is supported by WSJT-X if you specify the correct serial port and enable the "PTT via RTS" option. You cannot connect both USB cable and RJ-45 to DE-9F adapter cable to the K3S at the same time, and use both. That doesn't work. You cannot have two programs (like logging softare plus WSJT-X) connected to the same COM port at the same time. There may be nothing wrong with the K3S, just a lack of understanding how to configure the PC software to key the radio for digital modes. The FT8 software (WSJT-X and JTDX), supports both PTT via RTS and also PTT via "CAT", which means it just sends "TX;" and "RX;" commands and CONFIG:PTT-KEY may be left set to OFF-OFF if using PTT via CAT commands. But PTT via RTS should also work. If you want to key PTT via RTS and CW via DTR you must set CONFIG:PTT-KEY to RTS-DTR. You can verify that pulling the RTS Pin of the virtual serial port "High" keys the radio (and DTR keys CW), using my two free programs: https://bit.ly/ToggleRTS https://bit.ly/ToggleDTR These links download a Zip file with a Windows executable. Extract and read instructions in Readme.txt IE make a shortcut to the .exe file and set the path for the comm port that comes up when you plug in the USB-B to the KIO3B, example; C:\Elecraft\ToggleRTS\ToggleRTS.exe COM28: 1000 Keith WE6R ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [email protected]
