If you are directly connecting a serial port signal pin to the K3 ACC PTT, that will cause trouble, and may damage the K3. The voltages out of a serial port can be up to 25 volts, both positive and negative. You need some sort of conversion (a single transistor keying circuit) to drive the K3 PTT input between 5 volts and ground levels.
On the other hand, the K3 already has provision for PTT and Keying through the serial port DTR and/or RTS signals. You probably have a serial cable between the K3 and the PC for loading firmware, so use that connection and set the CONFIG: PTT--KEY menu to whichever line your software is using for PTT. 73, Don W3FPR On 9/20/2011 11:42 AM, DK5EW wrote: > Hello all, > I have a small problem with PTT via com port and ACC plug. > I made a 2 pin cable 9pol from PC to ACC 15pol to K3. > I soldered pin 4 for PTT and pin 5 for ground. > I tested it for correct wire and short - all O.K. > Now as soon I connect the TRX-ACC and the com port (serial 9 pin) to my > PC the K3 goes on TX. > Any solution out there ? > ______________________________________________________________ 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
