67' is very close to a half-wave on 40 m and a full-wave on 20 m. In theory the SWR should be insanely high, so I'm surprised the K1 ATU handled it on 20 m. Even if it did, the losses would be very high. Best to use lengths that aren't close to a multiple of a half-wave on any target band.
Wayne N6KR On Apr 24, 2012, at 10:11 AM, Niel Wiegand wrote: > Robert, > > I've found that the KX3 ATU loads up a 58' endfed wire just fine on > all > bands, but it can't load up everything. The 67' endfed wire I have > (which, in theory, is very tough to load up) could be loaded up on 20 > with the K1 ATU. The KX3 ATU can not handle it. > > So, for your loop, depending on the size, you may or may not have > trouble depending on the length. For a closed loop I believe you > want to > avoid odd multiples of half wave lengths. If the possible length you > have is pretty inflexible and the KX3 ATU can't handle it you can try > inserting an insulator half way around making it an open loop. > > 73, > Niel - W0VLZ > KX3 #43 > >> Message: 21 >> Date: Tue, 24 Apr 2012 12:50:28 +0000 >> From:[email protected] >> Subject: [Elecraft] KX3 ATU >> To: "Elecraft"<[email protected]> >> >> >> Does anyone know what the capability/efficiency of the internal ATU >> is? >> >> Not talking about the wattage (its up to 20 I believe) but the >> tuning the SWR/range >> >> Looking at deploying a random wire/loop so I am wondering if I need >> a separate ATU or can the internal unit handle the range? >> Thanks >> Robert >> >> a 'kosher' ham >> Sent from my BlackBerry device > > ______________________________________________________________ > 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
