OK. I did not recognize the high angle radiation pattern. One more genius
idea into the trash. I will do the standard thing of running it from tree
to tree so it is horizontal. you'da thought with all the chemistry I
studied back in the day, I would have known that.. Too soon old, too late
smart.
David Voit
WB6TOU
On Sat, Apr 22, 2017 at 3:06 PM, <w5prchuck@gmail.com> wrote:
> You mean a lot of high angle radiation, don’t you?
>
>
>
> Chuck W5PR
>
>
>
>
>
> Sent from Mail <https://go.microsoft.com/fwlink/?LinkId=550986> for
> Windows 10
>
>
>
> *From: *Tom Osborne <w7why1@gmail.com>
> *Sent: *Saturday, April 22, 2017 3:39 PM
> *To: *David Voit <dvoit1944@gmail.com>
> *Cc: *towertalk@contesting.com
> *Subject: *Re: [TowerTalk] On the subject of random wire antennas
>
>
>
> It all depends on what your interests are.
>
>
>
> A long vertical has a lot of horizontal takeoff compared to a quarter wave
>
> antenna. That is why the 40 meter vertical isn't a DX antenna. 73
>
>
>
> Tom W7WHY
>
>
>
> On Apr 22, 2017 11:28 AM, "David Voit" <dvoit1944@gmail.com> wrote:
>
>
>
> I am going to put up a random wire as a vertical in a tall pine tree and
>
> place a remote tuner at the feed point and fed with coax. Looking over the
>
> info on random wires, there are various lengths to avoid depending on the
>
> bands you choose to use. I certainly want 80 meters and I see a variety of
>
> lengths, 72, 85, 106 feet are acceptable. All of those can be put up in my
>
> trees with my pneumatic launcher and they would be a straight vertical
>
> wire. If I want to use 160 meters, it looks like the shortest wire would
>
> be 136 feet and the trees don't go that high. (I already have a quarter
>
> wave vertical for 160 at 123 feet and it works fine. Just don't have the
>
> extra 13 feet and don't want to wait for the tree to grow.)
>
>
>
> I believe the best answer is to leave the quarter wave wire up and put up
>
> the other antenna. Of course, I don't want to do that as it requires
>
> another coax run. I would like to do one random wire for access to all
>
> bands from that antenna, so, my question is would it work to put 136 feet
>
> of wire up and over the top and headed back down but with maybe 3 or 4 feet
>
> separation for the "hook" at the top? I would guess 5 or 10 feet would be
>
> more or less parallel to the portion going up but looping back down. Luck
>
> would decide how much is over the tip. If the over the top hook causes
>
> problems, I would default to the "best answer".
>
>
>
> The next part of the question is: for a vertical wire, assuming I should
>
> not do the 136 foot wire, is there an advantage for choosing the longer
>
> length among the choices for 80 and above? Angle of radiation?
>
> Efficiency, (given the feed point impedance is high, does this relate to
>
> low ground losses)? I know many radials are important for a quarter wave
>
> vertical but is it for a random wire?
>
>
>
> And yes, I understand lightning is a problem. I'm having fun and gladly
>
> disconnect after use. This does have the advantage of not needing relief
>
> from the tree swaying in the wind since it is parallel to the trunk. My
>
> dipole has to be lowered after I use it just to be sure it does not pull
>
> apart.
>
>
>
> David Voit
>
> WB6TOU
>
> _______________________________________________
>
>
>
>
>
>
>
> _______________________________________________
>
> TowerTalk mailing list
>
> TowerTalk@contesting.com
>
> http://lists.contesting.com/mailman/listinfo/towertalk
>
> _______________________________________________
>
>
>
>
>
>
>
> _______________________________________________
>
> TowerTalk mailing list
>
> TowerTalk@contesting.com
>
> http://lists.contesting.com/mailman/listinfo/towertalk
>
>
>
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|