Don, Did I not see a picture of your shack with a Matchbox, or am I thinking of someone else?
As sweet as the link coupling is, I would think a servo controlled box could be designed as an automatic unit... perhaps Wayne could be talked into designing one starting at QRP level and eventually designing a QRO linker. 73, Bill K9YEQ -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Don Wilhelm Sent: Monday, September 10, 2012 1:46 PM To: Ron D'Eau Claire Cc: [email protected] Subject: Re: [Elecraft] static buildup on antennas Yes, link coupled tuners will solve a lot of those problems. There is no DC path from the antenna to the transceiver. However, those link coupled tuners have been disappearing from the face of the earth at a rapid rate. They are not easily band-switched (the Johnson Matchbox units were an attempt, but the matching rang was limited)/ 73,\ Don W3FPR On 9/10/2012 2:31 PM, Ron D'Eau Claire wrote: > It gets tricky when the antenna feed point impedance is several > thousand ohms such as I see with my 130 foot inverted L on 80 meters > or with the common open wire fed multiband doublets. > > In those cases it's common to use a resistance of 100K or more to > avoid excessive losses in the resistors. > > But, such large resistances require more time to bleed off the > accumulated voltage. At some point they can no longer drain the charge > as fast as it accumulates and become ineffective. > > My favorite "tuner" for such antennas has always been a link-coupled tuner. > No direct-current connection between the antenna and the rig and a d-c > path to ground for the antenna at all times. But such tuners are not > conducive to fast, automatic operation. > > 73, Ron AC7AC > > > ______________________________________________________________ > 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
