Rick, for many years we used a 40M DL dimensioned as you describe at our field
day 40 cw station and was always good for 800-1000 Q's on 40cw. We did not
however go to the trouble of using a matching section, just fed it with 50ohm
coax and used the internal tuner in the rig to clean everything up. After all
it IS field day! But it was a great antenna for the amount of materials and
real estate required. Since we never tried a dipole or inv vee at the same
height at the same time I can't speculate as to the difference in
effectiveness, all I can do is state the results.
73 - Art N4UC
> From: Rick@DJ0IP.de
> To: tentec@contesting.com
> Date: Sun, 23 Nov 2014 18:59:35 +0100
> Subject: Re: [TenTec] 17 Meter Antenna
>
> George,
>
> Some hams are into the sport of amateur radio for the technical aspects alone.
> Others are in it for the sake of communicating.
>
> Those of us who are in it for the sake of communicating, judge the value of
> an antenna for its ability to help us reach DX destinations that we have
> trouble reaching with some other antenna.
>
> In this respect, this simple and cheap antenna stomps a low dipole (at least
> on 40m where I have used it the most) and holds its own against a vertical
> with 32 or more radials.
> This is not speculation. It is my experience using this antenna.
>
> I have erected this antenna just for contests at least a dozen times, at
> several different QTH's and the results were always the same. The standard
> antenna normally in use was a dipole about 40 ft. high.
>
> With this antenna, from Germany, and a couple other countries where I have
> operated with it, stateside, JA, VK, etc. are typically 1 to 2 S-Units
> stronger than on the standard dipole, all the time. I found it much easier
> to work these stations with the loop than on the dipole.
>
> This thread is about suggesting a good antenna for 17m.
> I have suggested one, including how I built it.
>
> You have poo-pooed my suggestions a couple of times without contributing
> anything useful towards the original problem: helping improve the signal on
> 17m. I welcome critique, but then I kind of expect an explanation to follow.
>
> I'm not a crack-engineer; just a ham with a lot of experience and nearly 20
> first place certificates in CQWW DX - most as a team member (MS or MM), but
> several as a single op working alone.
> In order to place high in a contest, you have to use antennas that work well.
> This antenna has worked well for me and has helped enable me, as well as my
> team to win contests.
>
> I welcome any suggestion you may have for improving this one or for something
> which works even better.
> Thanks.
>
> Now to answer your question. "No".
> Although I have two antenna analyzers, I did not own one the first few times
> I built this antenna 34 years ago. I only measured the SWR and then used it
> successfully in contests.
>
> The next time I build it, I will attach a half wavelength of feedline to it
> and measure the impedance. It's kind of difficult to physically reach the
> feedpoint. Will be interesting to see what it shows.
>
> 73 - Rick, DJ0IP
> (Nr. Frankfurt am Main)
>
>
> -----Original Message-----
> From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of george
> fritkin via TenTec
> Sent: Sunday, November 23, 2014 6:15 PM
> To: Discussion of Ten-Tec Equipment
> Subject: Re: [TenTec] 17 Meter Antenna
>
> Really, did you measure the impedance at the feed point?
> George, W6GF
>
> On Sunday, November 23, 2014 8:50 AM, Rick - DJ0IP / NJ0IP
> <Rick@DJ0IP.de> wrote:
>
>
> GM George,
>
> The advantage of this type of delta loop is, at low heights, the loop fed
> vertically polarized has a lower radiation angle than the dipole. The dipole
> will have to be raised a lot higher to match its radiation pattern. The loop
> is also more broad banded. Its advantage over a quarter wave vertical is,
> you don't need to put lay a bunch of radials, which often can be a nuisance.
>
> As for how to feed it, well I have been feeding loops like this for 35 years
> and they have been giving me outstanding results. That does not mean a
> perfect match but good enough to use without a matchbox. Of course the
> impedance varies with height above ground.
>
> If you have a better idea on how to feed it, please share it with us.
> I'm always happy to learn something new.
>
> My source of information on how to feed this type of antenna is from DL1BU
> (SK, and ex- chief technical Engineer of the DARC) in his article on loops,
> printed in the 1979 issue of CQDL magazine, page 154.
>
> 73 - Rick, DJ0IP
> (Nr. Frankfurt am Main)
>
>
> -----Original Message-----
> From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of george
> fritkin via TenTec
> Sent: Sunday, November 23, 2014 4:40 PM
> To: Discussion of Ten-Tec Equipment
> Subject: Re: [TenTec] 17 Meter Antenna
>
> Delta loops show marginal gain over a dipole (1.1db), and are much more of a
> pain to erect. As far as noise no real proof that is true. And one more
> thing, feeding with 1/4 wave of 72ohm is more voodoo engineering you find
> here George, W6GF
>
> On Saturday, November 22, 2014 11:18 PM, Rick - DJ0IP / NJ0IP
> <Rick@DJ0IP.de> wrote:
>
>
> Use a telescoping fiberglass pole.
> They don't have to be very high.
> 25 ft. is high enough if you make the horizontal bit a little longer.
> That still leaves about 7 or 8' under the antenna so that people can walk
> under it.
> Scott (W4PA) sells 40' poles. One of those would be perfect.
>
> 73 - Rick, DJ0IP
> (Nr. Frankfurt am Main)
>
>
> -----Original Message-----
> From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of Reed
> Sent: Sunday, November 23, 2014 4:17 AM
> To: tentec@contesting.com
> Subject: [TenTec] 17 Meter Antenna
>
> I'm sure Gary they are the best antenna for the dollar, but not enough trees
> here for support. I was raised on a farm & my late father, W4PFP & elmer,
> had some serious wire antennas. I miss the real estate, but not the farming.
>
> Reed W4JZ
>
>
> Reed,
> I had a 80M Delta loop up for quite a few years. It worked extremely
> well. Very quiet. It was fed in the corner with 75 ohm coax, then 50 ohm to
> the shack. My matching piece of 75 ohm coax was abt
> 46.5 feet long (1/4 wave x velocity factor of the cable). I'd put another up
> but all my trees have grown up.
>
> Gary - KN0V
>
>
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