Re: [Elecraft] OT: G5RV's antenna
I am with Ken on this one. I use a 130 foot classic Zepp with 600 ohm ladder line to a balun and then a short coax line to the K-3 with internal tuner. It tunes very nicely on all HF bands 160 to 10. (Yes, even 160.) Kim - K7IM -Original Message- From: Ken G Kopp [mailto:kengk...@gmail.com] Sent: Friday, March 09, 2012 6:54 PM To: elecraft@mailman.qth.net Subject: [Elecraft] OT: G5RV's antenna I have Varney's (G5RV) original article. The antenna was designed for -only- 20M . Since then it's taken on the proverbial life of it's own and become somewhat of a cult antenna, as is the case with the Carolina Windom. Why would one start with a perfectly good balanced-line fed Zepp, cobble a piece of special-length coax onto the end of that balanced line so that the antenna becomes something else, and then have to use an antenna tuner to make the thing work? Since the antenna requires a tuner, why not connect the balanced line to a balanced tuner ... or one with a balun ... and enjoy all the virtues of a classic Zepp? 73! Ken Kopp - K0PP elecraftcov...@gmail.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] OT: G5RV's antenna
OK, I amend my post to say 130 foot doublet. Kim - K7IM -Original Message- From: Ron D'Eau Claire [mailto:r...@cobi.biz] Sent: Friday, March 09, 2012 8:09 PM To: 'Ken G Kopp'; d...@w3fpr.com Cc: elecraft@mailman.qth.net Subject: Re: [Elecraft] OT: G5RV's antenna The feeder was exactly 1/4 wavelength long so it transformed the very high impedance at the end of the radiator to a very low impedance at the rig in the Zeppelin, minimizing RF in the Shack issues. Since the radiator was 1/2 wavelength long, very little current flowed from the feeder into the radiator. It was a voltage loop. That meant that, although the other side of the feeder was terminated in an insulator, the currents along the feed line were well balanced. Most radiomen of the time considered that the leakage current into the insulator closely matched the current into the radiator so the balance was very good indeed. The next step, coming back to Don's comment, was to connect two Zepps back to back for some additional gain. Extending the radiators beyond 1/2 wavelength enhanced this effect and, since it was now a center fed antenna, feedline imbalance was no longer a danger, hence the popularity of the extended double Zepp. I am always careful to call my center fed wires a doublet to avoid confusion but many Hams today incorrectly call any wire fed at the center with open wire line a Zepp. Feeding a traditional Zepp only minimizes feed line radiation when the radiator is exactly 1/2 wavelength. (The feeder can be any length if you can deal with the feed point impedance at the rig end.) However, many Hams have reported excellent results with Zepps with not-1/2-wave long radiators. In those cases the feed line is also part of the radiating antenna. That can be good when the feeder is in the clear and less so if it's not. The same is true of most off center fed antennas. 73, Ron AC7AC -Original Message- From: elecraft-boun...@mailman.qth.net [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Ken G Kopp Sent: Friday, March 09, 2012 7:34 PM To: d...@w3fpr.com Cc: elecraft@mailman.qth.net Subject: Re: [Elecraft] OT: G5RV's antenna Yes Don, I knew when I used the term classic Zepp that I was taking a bit of liberty with the term. The original Zepp was indeed end-fed from the cabin of a Zepplin. I've often wondered how long the feeder actually was. They may have been closer to a simple end-fed wire. I'd also noted the concept repeated in the J-pole. We old ops have certain advantages ... 73! Ken On Sat, Mar 10, 2012 at 3:23 AM, Don Wilhelm w3...@embarqmail.com wrote: Ken, I will agree with all until I got to the end of your post - classic zepp The original (and classic) Zepp antenna was a 1/2 wave wire fed through a 1/4 wave transmission line connected to the end that was trailed behind lighter-than-air aircraft (Zepplin). If you look at the J-pole, and turn it horizontally, you will see exactly the same thing - a 1/4 wave transmission line with one side connected to a 1/2 wavelength radiator. I am not sure how the Zepp term became associated with any kind of center fed dipoles, but it has in ham circles, and I find it confusing - there is the Center Fed Zepp (2 halfwaves in phase) antenna, and then there is the Extended Center Fed Zepp (5/8 wavelength each side of center), and then there is the classic Zepp that is the antenna designed for trailing the aircraft. So we must be careful to explain which kind of Zepp antenna we are referring to when we write Zepp There is a lot of difference. 73, Don W3FPR __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
[Elecraft] KX-1 for sale
KX-1 for sale: KX-1 QRP CW Transceiver KXB30/80 adds 30 80 meters and some additional SWL to the basic 20 40 rig KXAT1 internal automatic antenna tuner (also has a manual function to tune into the SWL bands.) KXPD1 paddles attaches onto front of rig. Great shape, used lightly, never outdoors. $425 shipped USPS to USA K7IM kbott...@rafn.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
[Elecraft] KX-1 For Sale
I have a KX-1 with ATU, 30/80 option, paddles for sale. Also could include a small 12 volt 3 amp power supply. I have run it off the internal batteries and this small supply successfully. Cute little rig, but now that the KX-3 has appeared I am willing to sell it. kbott...@rafn.commailto:kbott...@rafn.com Seattle area. Cheers! Kim - K7IM __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
[Elecraft] K-3 used value
I paid 76% of the new price on EBay for a fully loaded factory built K-3 late last year (S/N in the 3500's). (Sub Receiver, 100w, ant tuner, 10 filters, etc...) I only had to add the general coverage modules for each receiver. Cheers! Kim - K7IM -Original Message- From: elecraft-boun...@mailman.qth.net [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of elecraft-requ...@mailman.qth.net Sent: Wednesday, April 20, 2011 9:00 AM To: elecraft@mailman.qth.net Subject: Elecraft Digest, Vol 84, Issue 36 Send Elecraft mailing list submissions to elecraft@mailman.qth.net To subscribe or unsubscribe via the World Wide Web, visit http://mailman.qth.net/mailman/listinfo/elecraft or, via email, send a message with subject or body 'help' to elecraft-requ...@mailman.qth.net You can reach the person managing the list at elecraft-ow...@mailman.qth.net When replying, please edit your Subject line so it is more specific than Re: Contents of Elecraft digest... __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] K3 RX Ant question - KBPF3 not working.
I find that my KBPF3 makes SWL worse. If I turn it off in the configure menu it works much better, so I must think it is not working. I sent a message to K3 support and am waiting for an answer. My KBPF3 is brand new so I am guessing that despite wearing the wrist grounding strap and using a ground pad the static may have gotten mine. Kim - K7IM -Original Message- From: Alan Price [mailto:w1...@arrl.net] Sent: Sunday, September 05, 2010 8:50 AM To: Elecraft Subject: [Elecraft] K3 RX Ant question I have a K2 with the KBPF3 option, among others. When I listen to the BC band with the KBPF3, it sounds great, but when I listen to any shortwave frequencies, the KBPF3 does not make a real difference. Am I missing something? 73 Alan W1HYV __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] advice on rig
Susan, I am no expert, however I sold an Icom 756ProIII and bought a K-3. I would not move down to a ProIII if I were you. The K-3 is light years better, that is of course just my nonprofessional opinion. Cheers! Kim - K7IM -Original Message- From: elecraft-boun...@mailman.qth.net [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Tony Morgan Sent: Friday, August 20, 2010 12:37 PM To: Elecraft Subject: Re: [Elecraft] advice on rig Susan, If you're sure you want to step down, you might check out the Ten-Tec Omni VII. No complicated menus and very straight forward to operate. Good QSK. Not as nice looking as the K3. ;-) 73, Tony W7GO __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net 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:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
