Ed, For digital modes, you must provide audio input to the microphone connector - just use a stereo plug and connect the audio to the tip - the PTT is on the ring, so you only need 3 plugs, one for the headphone jack and one for the microphone jack, and the other for the ACC1 (data) jack.
It might prove useful to construct a variation the interface Skip Teller KH6TY published in QST for July 2010. The "variation" is to add wires from RXD and TXD (plus Signal Ground) to a 3.5mm stereo plug (effectively adding your own version of the KX3SER cable) I believe it provides exactly what is needed for the PTT Data mode operation - plug it into a real serial port or the K3USB cable (or similar USB to serial cable). At least, that is how I would do it if I wanted everything to be in one package. 73, Don W3FPR On 3/6/2012 4:01 AM, Edward R. Cole wrote: > Following this thread with Lance, carefully. I'm not sure I will run > eme with my KX3 but will probably run WSJT on the 600m band. My 600m > transmitter uses a P&B dc relay for TR so need more delay. Can I not > use my K3USB cable and tap out the RTS line (DB9 pin7) to control the > GPIO line to accomplish PTT with sw control? Will use of the GPIO > line require special changes to the firmware to accomplish PTT? > > Most soundcard sw utilize RTS for PTT, so this issue is not limited > to just WSJT. > > 73, Ed - KL7UW > ------------------------------ > > Message: 14 > Date: Mon, 05 Mar 2012 14:13:32 -0500 > From: Don Wilhelm<w3...@embarqmail.com> > Subject: Re: [Elecraft] Elecraft KX3 Owner's Manual now available > (*preliminary*) > To: w...@q.com > Cc: Elecraft Mailing List<elecraft@mailman.qth.net> > Message-ID:<4f55105c.6040...@embarqmail.com> > Content-Type: text/plain; charset=ISO-8859-1; format=flowed > > Lance, > > You should not need another USB cable, but use the KXSER cable (and a > USB to serial adapter if needed) which will give you access to the RTS > and DTR pins of the serial port. > Yes, you will have to add the wires to the existing KXSER cable. > > 73, > Don W3FPR > > > > > 73, Ed - KL7UW, WD2XSH/45 > ====================================== > BP40IQ 500 KHz - 10-GHz www.kl7uw.com > EME: 50-1.1kw?, 144-1.4kw, 432-QRT, 1296-?, 3400-? > DUBUS Magazine USA Rep dubus...@gmail.com > "Kits made by KL7UW" http://www.kl7uw.com/kits.htm > ====================================== > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
