I have seen this happen when the K3 was connected to a computer via either USB or an RS232 serial cable and the computer was polling the K3 at a rapid rate (like several times a second) to determine its’ frequency and/or other operating parameters. This can cause the K3 to miss the data line signal from the KPA500. My solution was to slow the polling rate of the PC software.
73, Charles, K4ZRJ > On Jul 5, 2020, at 17:07, Tom Doligalski via Elecraft > <[email protected]> wrote: > > I have a relatively old K3, which I use together with a KPA500 and a KAT500. > Most of the time this works flawlessly. > > However, occasionally the K3 gets confused and doesn’t realize that the > KPA500 is in “Operate” mode (rather an in standby). This results in the K3 > sending 100 watts to the amp, and the amp faults. > > Again, this doesn’t happen often, and I can’t ascertain why it occurs. Most > of the time all is OK. > > The K3, KPA500 and the KAT500 all are running the latest firmware. > > Any idea? > > 73 > > Tom W4KX > ______________________________________________________________ > 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] ______________________________________________________________ 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]

