Rick:
Thanks for the info on the open wire spreaders. My supplier of 600 ohm
parallel line recently passed away and his company has been shut down. I'll try
your www.dx-wire.de site. The spreaders look very nice. I totally concur with
your comments on the 450 ohm (or even 300 ohm) twinlead line. I've found that
rain, snow, ice, etc. affect that type of plastic coated line much more than
the 600 ohm line.
73
Scott K4VWK
-----Original Message-----
>From: Rick - DJ0IP / NJ0IP <Rick@DJ0IP.de>
>Sent: Dec 29, 2014 4:52 PM
>To: 'Discussion of Ten-Tec Equipment' <tentec@contesting.com>
>Subject: Re: [TenTec] Antenna help
>
>Curron,
>
>As with all similar questions, you will need to give us more information
>before we answer.
>
>Jim's answer might be right but it might not be.
>It all depends on several factors.
>
>Up front, my opinion of this antenna is, if I could have just one antenna
>for the rest of my life, this is exactly the antenna I would choose. IMO,
>no other antenna covers so many bands in so many directions as well as this
>antenna.
>
>Scott's article is excellent. I strongly recommend you download and read
>it. Pay particular attention to what he says about antenna tuners. There
>is a lot of mis-information floating around about how to match openwire fed
>antennas. Without a doubt, a symmetrical tuner is by far the best way to
>go.
>If you are going to run more than a couple hundred watts, it's the only way
>to go.
>Otherwise you may find yourself up to your antlers in common-mode-current.
>
>If you use an asymmetrical tuner, it is much better to use a 1:1 balun than
>a 4:1 balun - even if you have to play with feedline lengths. This assumes
>you have a fairly decent ATU. Most auto-tuners won't work here.
>
>If you must use an asymmetrical tuner and want to run high power AND your
>matchbox won't get by without a 4:1 balun, then you must insert a 1:1
>Guanella between the matchbox and the 4:1 balun. Otherwise you may find
>yourself up to your antlers in CMC.
>
>450 Ohm windowline (i.e. Wireman) will work and is what I usually use for
>portable work, but for home use it is better to build your own openwire.
>Use spreaders that snap in place; something like this:
> http://www.73cnc.com/product_p/ls250.htm
>
>My favorite (by far) are here:
>http://www.dx-wire.de/lng/en/huehnerleiter-spreizer/?language=en
>They come in 4 different widths. He will ship to stateside.
>
>I have seen a couple other similar products in the states.
>Don't fool with spreaders where you must thread the wires through the holes.
>You'll end up as crazy as me.
>
>Curron, here are some questions:
>
>>> What bands do you intend to work with this antenna? (list them all,
>don't just say other bands)
>>> Will this be your only antenna? If not, list the others you have or plan
>to have.
>>> When working 80m with this antenna, is your main interest DX? Or do you
>wish to rag chew all around the states?
>>> Which antenna tuner were you planning on using (make and model)
>>> How much power will you be running.
>
>Again, if at all possible, you should use a symmetrical matchbox. There
>aren't a lot of these on the market.
>I have compiled a fairly comprehensive list on my web, divided into low
>power and high power matchboxes.
>> www.dj0ip.de/antenna-matchboxes/symmetrical-matchboxes/low-power-atu-s/
>> www.dj0ip.de/antenna-matchboxes/symmetrical-matchboxes/high-power-atu-s/
>
>If you can find an old Johnson Viking Matchbox (either the 275w or Kilowatt
>version), I strongly recommend installing the modification I show on my web
>site:
>www.dj0ip.de/antenna-matchboxes/symmetrical-matchboxes/j-viking-upgrade/
>This will significantly improve its matching range and provide a better
>match on several bands.
>
>In summary, if you are looking for an @ss-kicking DX antenna for 80, as Jim
>said, there are better antennas.
>But if you're looking for a good performing omni-directional antenna on 80
>that will also work well on all other bands, this one is perfect for the
>job.
>
>73 - Rick, DJ0IP
>(Nr. Frankfurt am Main)
>
>
>-----Original Message-----
>From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of Curron
>Sent: Monday, December 29, 2014 7:51 PM
>To: tentec@contesting.com
>Subject: [TenTec] Antenna help
>
>
>
>Need some help folks...
>
>I would like to get some input on building an 80 meter sky loop antenna that
>I will use on 80 and other bands with an antenna tuner. I have some nice
>tall pine trees to run the corners to and I plan on joining the loop to the
>house with 450 ohm ladder line. Just under the edge of the house I will
>install a balun and bring it into the house with low loss coax. Please make
>any comments or offer any advice you can. I am hoping to learn from your
>experiences. Some questions I have are:
>
>- What kind of wire should I use for the loop antenna
>
>- What type of rope that will hold up to the UV and time (so much just falls
>apart these days)
>
>- What balun, 4:1, 1:1 ?
>
>- Is 450 ohm feed ladder line the best to use? This part will be about 80
>feet long. Will this length be a problem?
>
>- Has anyone ever had any issues using
>delrin for the insulators? Is there a better?
>
>- I am thinking about placing a screen door spring on each corner to allow
>the trees to sway in the wind. anyone ever tried that. Or should I just
>counter weight to opposing corners of the loop?
>
>- How's the best way to protect this
>setup from lightning?
>
>Thanks in advance for any help!
>
>
>
>73
>
>Don kb3drw
>
>
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