Hi Dave, The K3s (and K3) bypasses the 100 watt PA module when you set the Power control to less than 11 watts and relies on the KLPA3A 10 watt PA driver module. No harm will come to the K3s when operating at 5 watts presuming you have an SWR within spec for the K3s.
I used a simple optocoupler interface to key my K3 from N1MM+ function keys in CW contests, but replaced it with a Mortty, which emulates the WinKey protocol from a USB port on the computer. There are a variety of single transistor keying interfaces described on the web if you search a bit. Others may recall if one can share the K3s serial port for both rig control and CW keying without a separate interface circuit - I remember seeing various discussions on this issue years ago, but can't retrieve them now. 73, Mike, K8CN ______________________________________________________________ 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 Message delivered to arch...@mail-archive.com
