Dear Bill,
I too have had (have) something of the same problem. For a long time I could transmit 20 W only on digital modes on 80 meters. If transmitting more power the K3 would lock in transmit mode and I would have to turn it off to stop it transmitting. Now I have bought a pair of Line In Line Out cables with very good shielding. I can now transmit at least 250 W without locking the K3 in transmit mode. My next problem is that when using Ham Radio deluxe (HRD) to control the K3 the HRD locks up so I have to close the program and start again if I want to do any changes in frequency, power or whatever. Other programs running on the computer at the same time do not lock up. So my guess is that it is my COM port that locks up. I may try using some better shielded cable for the COM port. I haven't had the time yet. Best regards OZ1CCM Kjeld -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Bill Davis Sent: 6. april 2014 02:10 To: Elecraft Mailer Subject: [Elecraft] RF into K3 via serial port? In my transition to Win7, I added a 2 port serial PCI card (NewEgg purchase -- Sunix 5037A) to my Dell PC. I was going to use one of these 2 ports to communicate with my K3 Utility terminal program. Very handy CW / RTTY application. Shortly after installation I made a nice contact on 30m RTTY and then moved to 80m RTTY. SURPRISE!! During TX the K3 hung in TX and only a couple of characters (if that) were ever transmitted. I was attempting to run about 70watts or so. Only by reducing power to a few watts would the RTTY transmission seemingly be successful. The 80m antenna is resonate and very low SWR even without the KXPA100 tuner. (My K3/10 is for VHF/UHF/Microwave IF use mostly, hence the external PA/Tuner). So RF is getting back into the K3 .. odd ... nothing is "hot" in the shack at all. My workaround is to use the new serial ports for other hardware/applications and use the one serial port in the Dell Dimension 4700 for the K3 / terminal program. Things are happy that way. I may investigate and try a ferrite core on the serial cable. But I will need to get an "HF" core since all of mine are for higher freq use. I just thought this was really odd. My serial cable is "homebrew" minimum conductor cable and I don't recall if it is shielded or not. Anyone else had any similar experiences?? 73 Bill K0AWU ______________________________________________________________ Elecraft mailing list Home: <http://mailman.qth.net/mailman/listinfo/elecraft> http://mailman.qth.net/mailman/listinfo/elecraft Help: <http://mailman.qth.net/mmfaq.htm> http://mailman.qth.net/mmfaq.htm Post: <mailto:[email protected]> mailto:[email protected] This list hosted by: <http://www.qsl.net> http://www.qsl.net Please help support this email list: <http://www.qsl.net/donate.html> http://www.qsl.net/donate.html Message delivered to <mailto:[email protected]> [email protected] ______________________________________________________________ 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]
