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Re: Fw: ELK or ARROW



Mr. Mc Bride,

Thank you for this post. It led me to a Google search, which provide a great starting point to go along with Item No. 3 in your post. It is:

http://www.dxzone.com/catalog/Software/Antenna_analysis/

Thank you again,

Tim - N3TL
-------------- Original message from "Art McBride" <kc6uqh@cox.net>: -------------- 


> To All, 
> 1. Amateur Radio is learning by doing. 
> 2. A large amount of data on Yagi type antennas exists, easily found, and is 
> well proven. 
> 3. Several design programs for antennas exist reducing construction time and 
> waist of materials. 
> 4. Equipment to measure comparative antenna performance at VHF/UHF 
> frequencies is not hard to find. 
> 
> Why do we line the pockets of some poorly designed antenna manufacturing 
> companies instead of learning how and making the best performing antennas 
> for our own use? If we do not learn these skills, no one will be left to 
> teach and the skills will be lost. 
> 
> There are many older Amateurs willing to teach those that want to learn, and 
> hopefully many of those wanting to learn are at least one half of the age of 
> those who can teach! 
> 
> Art, 
> KC6UQH 
> 
> -----Original Message----- 
> From: amsat-bb-bounces@amsat.org [mailto:amsat-bb-bounces@amsat.org] On 
> Behalf Of Jim Danehy 
> Sent: Saturday, December 27, 2008 6:33 PM 
> To: amsat-bb@amsat.org 
> Subject: [amsat-bb] Fw: ELK or ARROW 
> 
> 
> . there is the old adage that you get what you pay for . . . why buy a 
> poorly designed antenna that does not work very well 
> > ? 
> > 
> > If you have a 5 element yagi that only produces 4 dbi you are not getting 
> 
> > what you paid for . . . most 2 element yagis would out perform that 
> > statistic . . . a 5 element yagi should be at least 9 db + or 10 db dbd 
> > (dipole ) not isotropic . . . . there is something that is called 
> > MERCHANTABILITY . . .i.e., an IMPLIED WARRANTY that you are getting at 
> > least the minimum for your money . . . 
> > 4 dbi for an Arrow is way off base . . . so it is not just ; you can not 
> > afford a Cadillac but you are not even getting a Ford or Chevy . . i.e., 
> 
> > the gain of a 5 element yagi on 435 mhz . . . that is the issue, not cost 
> 
> > alone . . . . . . same comments apply to the ELK but I have attempted to 
> > make the point that there is a minimum performance for a certain number of 
> 
> > elements that is pretty OBJECTIVE and when it is not met . . . . well 
> > that is my point . . . these two antennas have shown to some testers that 
> > they do not measure up to the minimum EXPECTATIONS . . .unfortunately that 
> 
> > is acceptable to some . . . . then it becomes acceptable to many . . . 
> > and objectivity is abandoned . . . 
> > 
> > Jim W9VNE 
> > 
> > 
> > ----- Original Message ----- 
> > From: "Trey Brown" 
> > To: "Jim Danehy" 
> > Sent: Saturday, December 27, 2008 6:39 PM 
> > Subject: Re: [amsat-bb] ELK or ARROW 
> > 
> > 
> >> Thanks for the comments. Realize, though, that not everyone wants or 
> >> can afford to have the Cadillac. 
> >> 
> >> 
> >> On Sat, Dec 27, 2008 at 4:06 PM, Jim Danehy wrote: 
> >>> the Arrow antenna has been critiqued by Kent Britain, WA5VJB 
> >>> 
> >>> http://wa5vjb.com/references/Cheap%20Antennas-LEOs.pdf 
> >>> 
> >>> he says that some have measured the Arrow for gain on 435 mhz @ 4 dbi 
> >>> (isotropic) . . . . and that further analysis showed that for the 
> >>> element lengths used on 435 mhz that it peaks at 457 mhz and not 435 mhz 
> 
> >>> . . . Kent is a well respected VHF/UHF antenna person who has plenty of 
> >>> credibility . . . 
> >>> 
> >>> Kent opines that the Arrow, as built does not have its elements 
> >>> insulated from the boom. It uses dimensions for insulated elements . . . 
> 
> >>> so much for the Arrow . . . . 
> >>> 
> >>> Now for the ELK : a local friend of mine owns an Arrow and he uses it 
> >>> successfully. He bought an ELK and attempted to compare the Arrow and 
> >>> the ELK . . . . he could not make an across town QSO on 435 mhz from his 
> 
> >>> second story window with the ELK , so he sent the ELK back for a refund 
> >>> . 
> >>> 
> >>> I have worked and exchanged QSLs with several hundred satellite users . 
> >>> . .the majority of the folks that have worked and QSLed me (close to 250 
> 
> >>> + ) have been using either the Arrow or ELK based upon the information 
> >>> on their cards. So they are popular. Are they optimum ? A lot of 
> >>> anecdotal information would seem to say NO . . . 
> >>> 
> >>> Thirty-five years ago I worked Oscar 6 with a homebrew 2 mtr yagi that 
> >>> probably was worse than either the Arrow or Elk but I worked YV and KL7 
> >>> from Indiana on CW with about 15 watts to the 3 elements which my XYL 
> >>> waved around at my directions . . . not any more . . .what do I use 
> >>> these days : a pair of circular polarity yagis on 10 foot booms 
> >>> manufactured by M Square . . . . 
> >>> 
> >>> Folks ask what should they buy ? Maybe a Ford or maybe a Chevy . . . 
> >>> neither is a Cadillac . . . . 
> >>> 
> >>> Jim W9VNE 
> >>> _______________________________________________ 
> >>> Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. 
> >>> Not an AMSAT-NA member? Join now to support the amateur satellite 
> >>> program! 
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> >>> 
> >> 
> >> 
> >> 
> >> -- 
> >> Trey -- N5THX 
> >> 
> >> They who can give up essential liberty to obtain a little temporary 
> >> safety, deserve neither liberty nor safety. 
> >> - Benjamin Franklin 
> >> 
> > 
> 
> _______________________________________________ 
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