Hi Ruben The K3 also has problems with intense RF fields on the coax cables. I use a 3cx3000 amp which causes the K3 to stutter. Basically when driving the amp, the power output becomes erratic.
Common mode chokes helped a bit, however I still have problems. I dont have these problems on other radios. I am going to rewire the amplifier with some quad shield Habia coax. I will then use multiple common chokes per K9YC's recipe book. As a last resort I will mount the K3 in a shielded 19 inch rack cabinet. Although I not sure if this will help. I am using a single vacuum DPDT vacuum relay on the rf deck. The coax comes from the RF deck directly from the relay, then directly to the radio. Any suggestions for a fix, besides running qrp? John --- On Sun, 3/28/10, Ruben Navarro Huedo <runa...@gmail.com> wrote: > From: Ruben Navarro Huedo <runa...@gmail.com> > Subject: Re: [Elecraft] K3 unstable ssb power > To: elecraft@mailman.qth.net > Date: Sunday, March 28, 2010, 11:41 AM > Same here. > I have to overload a little ALC and CMP and it solves > almost all the > problem, but it continues. > Before the k3 i owned an Icom 7700 and with the correct ALC > and CMP it > had a very stable SSB Power. > > I am sure it can be solved with a firmware update. > > El 28/03/2010 20:30, Jan Erik Holm escribió: > > Doesn´t seem to be a fix. My K3 is just about the > same. > > > > Jim SM2EKM > > -------------- > > Juha Kasari wrote: > >> Thanks, > >> > >> Ok, so it is feature! > >> > >> Yes I have adjust MIC and CMP just like manual, > not effect. So there is no > >> solution to problem. > >> > >> juha > >> > >> > >> 2010/3/28 Dave, G4AON<elecr...@astromag.co.uk> > >> > >>> Juha this "problem" is an old one. Some time > back the K3 had poor ALC which > >>> allowed for overshoot on peaks, the firmware > was altered to soften the ALC > >>> control with the results you (and the rest of > us) experience. The power can > >>> slowly increase over the first few seconds on > SSB, the effect is less if you > >>> "TUNE" first via the front panel button. Also, > have you checked that you are > >>> driving the ALC meter reasonably well, as per > the manual? > >>> > >>> For comparison, my TS-480SAT is also quite > soft on ALC control with the > >>> peak power seeming to vary from one moment to > the next. With some previous > >>> radios I recall seeing the peaks on an > oscilloscope looking like a trimmed > >>> hedge, which is liable to create excessive > IMD. > >>> > >>> I use an LP-100 peak reading power meter and > the K3 is similar in it's > >>> peaks compared to my TS-480 with the same > linear (Acom 1000). I don't think > >>> it's anything to worry about. > >>> > >>> 73 Dave, G4AON > >>> K3/100 #80 f/w 3.79 > >>> ----------------------------- > >>> > >>> > >>> I have K3 #2100. On CW power is very stable, > but not on SSB. There is some > >>> change on output power, it is not constant. > >>> > > > > > ______________________________________________________________ > > 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 > > -- > Rubén Navarro Huedo - EA5BZ > http://www.palotes.com > ______________________________________________________________ > 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
