From karinann at tampabay.rr.com Tue Jun 14 13:00:45 2022 From: karinann at tampabay.rr.com (Karin Johnson) Date: Tue, 14 Jun 2022 13:00:45 -0400 Subject: [Antennaware] Interesting Antenna Design Message-ID: <12890440BC1C4AF5BC89C0D5BC7F9D73@KARINSPC> Hello Group: I recently have put up a wire antenna for 20 Meters. It is a three-eights wavelength wire vertical cut for the low end of the 20 Meter band. I have an appropriate matching network at the base of the vertical. It works like text book. So I've been thinking. I am a bit compromised with real estate and space for a few more antennas. You can never have enough antennas. So I was thinking, I am wondering if the 3/8 wavelength wire is resonant on any other band. Lo and behold, it is the perfect length for a 3/4 wavelength vertical wire for the low end of the 10 meter band. Sooooooooo ! ! ! I designed a new outside matching network to handle both bands. The new matching network incorporates two vacuum relays, a vacuum variable capacitor for the 20 meter portion, and a 1 to 4 balun for the 20 meter band. Plus at the shack end of the coax a Bias Tee inserter for control power of the relays. I am including link to Google Drive if anyone is interesting in seeing the design concept. It is below: https://docs.google.com/presentation/d/1RBxngC3pf0Uop47BVKCdPKaZac4260RU/edi t?usp=sharing&ouid=101983102297392238928&rtpof=true&sd=true I haven't seen much activity on this list for a while and thought I might provoke some comments. Regards, Karin Anne Johnson K3UU Palm Harbor, Florida From karinann at tampabay.rr.com Tue Jun 14 13:24:12 2022 From: karinann at tampabay.rr.com (Karin Johnson) Date: Tue, 14 Jun 2022 13:24:12 -0400 Subject: [Antennaware] Interesting Antenna Design - A Link Mistake Message-ID: <189030453B734CC79792FAE68A8082EE@KARINSPC> Hello again Group: I made a mistake I the supplied link. The correct link is below: https://docs.google.com/presentation/d/1Zwc5IGpdTRBByxyMgfnwDVLiEof1znUn/edi t?usp=sharing &ouid=101983102297392238928&rtpof=true&sd=true Karin From bw_dw at fastmail.net Tue Jun 14 13:45:12 2022 From: bw_dw at fastmail.net (bw_dw at fastmail.net) Date: Tue, 14 Jun 2022 12:45:12 -0500 Subject: [Antennaware] Interesting Antenna Design In-Reply-To: <12890440BC1C4AF5BC89C0D5BC7F9D73@KARINSPC> References: <12890440BC1C4AF5BC89C0D5BC7F9D73@KARINSPC> Message-ID: <9c027107-c31b-4f4b-8aba-f9b75f7544e1@www.fastmail.com> Nice Karin! You might eventually consider buying an automatic "L" network tuner. You might find that wire will play on a number of bands above 20. Have fun!! N1BBR On Tue, Jun 14, 2022, at 12:00 PM, Karin Johnson wrote: > Hello Group: > I recently have put up a wire antenna for 20 Meters. It is a three-eights > wavelength wire vertical cut for the low end of the 20 Meter band. I have an > appropriate matching network at the base of the vertical. It works like > text book. > So I've been thinking. I am a bit compromised with real estate and space > for a few more antennas. You can never have enough antennas. So I was > thinking, I am wondering if the 3/8 wavelength wire is resonant on any other > band. Lo and behold, it is the perfect length for a 3/4 wavelength vertical > wire for the low end of the 10 meter band. Sooooooooo ! ! ! > I designed a new outside matching network to handle both bands. > The new matching network incorporates two vacuum relays, a vacuum variable > capacitor for the 20 meter portion, and a 1 to 4 balun for the 20 meter > band. Plus at the shack end of the coax a Bias Tee inserter for control > power of the relays. > I am including link to Google Drive if anyone is interesting in seeing the > design concept. It is below: > > > https://docs.google.com/presentation/d/1RBxngC3pf0Uop47BVKCdPKaZac4260RU/edi > t?usp=sharing&ouid=101983102297392238928&rtpof=true&sd=true > > > I haven't seen much activity on this list for a while and thought I might > provoke some comments. > > Regards, > > Karin Anne Johnson K3UU > Palm Harbor, Florida > > _______________________________________________ > Antennaware mailing list > Antennaware at contesting.com > http://lists.contesting.com/mailman/listinfo/antennaware