Right now, I have the coax from the antenna directly connected to the KAT500. I could try using my Delta-4 switch, have the coax go to that and then a small run to the KAT500 to see if that makes a difference. The high swr is an issue on 40 and 10 meters, however, ten is manageable, it's about 1.9 - 1 and I am working around the issue but using my 80 meter vertical on 20 meters. So this is not a "show-stopper" but just wanted to understand why it was happening.
Jerry - AC4BT On Sat, Dec 8, 2012 at 4:14 PM, Vic Rosenthal <[email protected]> wrote: > If the feed line happens to be near an even multiple of a half wavelength > the impedance will be very high and there will be a voltage loop (HV point) > at the tuner. As someone else noted, losses would also be very high, so > using a 40m coax fed dipole on 20 is a poor idea. > > Vic k2vco > > On Dec 8, 2012, at 12:37 PM, "hawley, charles j jr" <[email protected]> > wrote: > > > Now that I think about it, if you have a different feedline length > depending on tuning from the output of the KAT or tuning from the output of > the K3 with both in line, that may make enough difference in the required > values to tune. > > > > Chuck, KE9UW > > Lionel Trains, TCA, LCCA, LRRC > > aka Jack, BMW Motorcycles BMWMOA #224 > > > > ________________________________________ > > From: [email protected] [[email protected]] > on behalf of hawley, charles j jr [[email protected]] > > Sent: Saturday, December 08, 2012 2:33 PM > > To: Jerry Weisskohl; [email protected] > > Subject: Re: [Elecraft] KAT500 Tuning issue > > > > One thing I ran into with an automatic "hi powered" tuner is that the > firmware does not allow all the otherwise available values of the > components on certain bands. This is done in the case of the MFJ tuner I am > using (now until the KAT arrives) on 40 Meters so that the voltage and > current limits are not exceeded when handling full rated power. I don't > know if the KAT500 has this implemented or if in the case of the higher > power capability, it just doesn't have quite the range of the 100 watt > tuner in the K3. > > As was mentioned in a similar thread, you might experiment by changing > your feedline a few feet plus or minus to find a more satisfactory matching > situation on some bands. > > > > Chuck, KE9UW > > Lionel Trains, TCA, LCCA, LRRC > > aka Jack, BMW Motorcycles BMWMOA #224 > > > > ________________________________________ > > From: [email protected] [[email protected]] > on behalf of Jerry Weisskohl [[email protected]] > > Sent: Saturday, December 08, 2012 1:57 PM > > To: [email protected] > > Subject: [Elecraft] KAT500 Tuning issue > > > > I believe I have run into a problem with the KAT500 tuner and wanted to > > mention it to see if anyone else is experiencing the same issue. I just > > received the KAT500 tuner and the KPA500 amp and got it up and running > > with my K3. The KPA500 works great but I am finding that the KAT500 is > > unable to tune my 40 meter wire dipole on 20 meters. The best it can do > is > > 3.75 - 1 swr which trips the FAULT light on the KAT500. The internal > tuner > > in the K3 has been able to tune this antenna on all bands without issue. > > Also the KAT500 is unable to tune 28400 below 2.5 - 1 while the internal > > tuner in the K3 has no problems tuning that frequency. I have two > antennas, > > my other one is a 80 meter vertical so I switch to that for 20 meters > but I > > don't understand why the KAT500 is unable to tune certain frequencies > when > > the internal tuner on the K3 is able to do so. > > > > I called Elecraft and spoke to David who had me take the KPA500 out of > the > > picture by connecting the KAT500 directly to the K3. I had the same > > results. David then sent me the latest unofficial KAT500 firmware 1.18 > > which I installed. It did not make any difference. > > David had me try tuning using the utility, again no difference and still > > unable to tune 20 meters below 2.75 - 1 on my 40 meter wire dipole. > > > > In general I am finding that the internal tuner does a much better job > > tuning my antennas then the KAT500. I wonder if anyone else is > experiencing > > the same problem. > > > > As far as the settings on the K3 I am using the following: > > COnfig:PWR Set = Per Band > > COnfig:Tune PWR = 15 > > > > I guess I will hope that this can be addressed through a later firmware > > release. Meanwhile, the KAT500 is the weak link in my system. The KPA500 > is > > fantastic, just need to resolve this tuner issue. > > > > Jerry - AC4BT > > ______________________________________________________________ > > 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 > > ______________________________________________________________ > > 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 > > ______________________________________________________________ > > 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 > ______________________________________________________________ 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
