I had the AV620 on a 40 foot tower for four years, unguyed. Used it as an SO2R second radio antenna, it performed well. It is rated to take 70 mph winds. After 4 years the base of the antenna started
The AV-640 is actually a 3/8 wave vertical. I measured it on all bands. That is why the need for the balun. And I am not so sure that it is 4:1. At 3/8 wave, the impedance is quite different from a 1
I?m going to beg to differ on the theory of operation of the AV640, specifically its native impedance and the use of the 4:1 unun (yes, it's wired as a unun). The 4:1 is not stepping up from 12.5 to
You are correct that the impedance is stepped down from 200 and not up from 12.5 which is what I get for going from memory. OT OH that the only spot where I see we disagreed. My AV-640 is at 40 feet
HyGain calls it a Windom, but a Windom is a single wire fed in from the end. The AV-640 in no way resembles a Windom. It is simply a 3/8 wave vertical and the counterpoise is the other side, analagou
<snip> Using 4 or 5 Fair-Rite cores you can build them that'll handle more power than that for about $30 each. 73 Roger (K8RI) _______________________________________________ ________________________
Straighten the "radials" into a single wire and the AV-620/640, or R5/R7/R8 certainly resemble an off center fed antenna - what it often called a "Windom." No, the high impedance is because of the o
Joe, Go to the ARRL antenna book and look at a windom. It DOES NOT have a break at the feed point for coax center and coax shield. It is a straight wire with the coax center at the off center point.
Gosh, All these comments makes me want to take my AV-640 out of storage and reinstall it. :-) 73, Jim N9WW James Chaggaris President PowerOne Corp./PowerOne Environmental 1020 Cedar Ave. Suite 203 St
Jim DO IT !!!!!!!! Dan Schaaf K3ZXL "In the Beginning there was Spark Gap" www.k3zxl.com -- Original Message -- From: "Jim Chaggaris" <jimc@pwrone.com> To: "'Tower and HF antenna construction topics.
TowerTalkians -- If you're going to reply to a post, would you mind terribly doing a little editing out of the previous posts? The replies to this thread now contain the previous FIFTEEN emails. This
Oops...:-( 73, Jim N9WW James Chaggaris President PowerOne Corp./PowerOne Environmental 1020 Cedar Ave. Suite 203 St. Charles, IL 60174 Phn: 630-443-6500 Fax: 630-443-6505 Website: www.pwrone.com --O
Dan, Amateurs have been calling off-center fed dipoles a "Windom" for more than 40 years. The oldest ARRL Antenna Book I have owned includes that same discussion. Whether you insist on calling only t
Joe, Believe what you like. I prefer to call it for what it really is. The AV-640 is a 3/8 wave vertical with elevated radials ( Counterpoise for those who prefer ). It has a balun for impedance matc
Joe Here is the better question to answer. At what point does a dipole or doublet or Hertz antenna stop being a dipole and start being a Windom in the general terminology that you offer? When it is 1
"Windom" Antennas. http://www.packetradio.com/windom.htm http://www.dxzone.com/cgi-bin/dir/jump2.cgi?ID=12135 A little history: http://hamwaves.com/cl-ocfd/history.html#early The 1956 ARRL Radio Amat
Wow... this was supposed to be a about comparisons with the GAP Challenger.. Can we say ADHD. <snip> Using 4 or 5 Fair-Rite cores you can build them that'll handle more power than that for about $30
Jim, Go ahead and get it done. Especially on 30 and 40 I've found the antenna to be killer. I'm reserving judgment on the higher bands till we get SFI up in the 80s or 90s again... Gosh, All the
What language is that? It ain't American, fer sure... -- 73 from Ian GM3SEK _______________________________________________ _______________________________________________ TowerTalk mailing list Towe
Look! A rabbit! --Original Message-- From: towertalk-bounces@contesting.com [mailto:towertalk-bounces@contesting.com] On Behalf Of Christopher Atkins Sent: Monday, April 26, 2010 7:43 AM To: Tower an