K3 unstable ssb power
Locked
 
|
Help!
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. If I tune my linear (Titan) on CW with 50 W, output is stable 1500 W. but on SSB with the same driving power I get only about 1200 W? If I whistle to mic it takes about 2-3 seconds and power rising to 1500W. Titan has peak power meter and I have also Bird 43. I have tested also to 50 ohm dummy load and without linear, with and without tuner. Really, power is first about 80 W and then it go to 100 W very slowly on SSB. TXG VCE has no effect. Why? Is that normal behavior of K3? I have latest firmware, today loaded. I think it is like ALC react too much and too quickly. 73 de Juha - oh6os ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
|
|
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:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
|
|
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 <[hidden email]> > 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:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
|
|
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 <[hidden email]> > >> 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:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
Re: K3 unstable ssb power
|
|
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<[hidden email]> >> >>> 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:[hidden email] > > 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:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
|
|
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 <[hidden email]> wrote: > From: Ruben Navarro Huedo <[hidden email]> > Subject: Re: [Elecraft] K3 unstable ssb power > To: [hidden email] > 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<[hidden email]> > >> > >>> 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:[hidden email] > > > > 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:[hidden email] > > 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:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
|
|
In reply to this post by Juha - oh6os
Hi Juha,
Are you use 2.7KHz filter? If so please check the shift freqency setting. One of my friend meet this problem on SSB mode, I checked his setting, found he did not correctly set the filter shift freqency. After set to correct value, no problem now. 73 de ba4rf,David 2010/3/29 Juha Kasari <[hidden email]> > Help! > > 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. > > If I tune my linear (Titan) on CW with 50 W, output is stable 1500 W. but > on > SSB with the same driving power I get only about 1200 W? If I whistle to > mic > it takes about 2-3 seconds and power rising to 1500W. Titan has peak power > meter and I have also Bird 43. > > I have tested also to 50 ohm dummy load and without linear, with and > without > tuner. Really, power is first about 80 W and then it go to 100 W very > slowly > on SSB. TXG VCE has no effect. > > Why? Is that normal behavior of K3? I have latest firmware, today loaded. I > think it is like ALC react too much and too quickly. > > 73 de Juha - oh6os > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[hidden email] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > -- -------------------------------- All the best! David,ba4rf ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
«
Return to [K3]
|
1 view|%1 views
| Free forum by Nabble | Edit this page |