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N8GAV
04-07-2011, 02:25 PM
Now that the weather is breaking time for a new antenna since the dublet took a beating this winter. Thinking of an Inverted Vee an oldie but goodie and I have trees that would give me 65' height at center. What do you guys think worth it or not??

WØTKX
04-07-2011, 02:36 PM
Always worth it. I am thinking of making a RX only K9AY loop array for weaker stuff and adding a sloper to blast more signal to the east.

Not much room in this yard, so minding the interactions may be tricky. May have to wait till I (finally) move to a better place for antennas, Though I do OK here, I'm similarly space challenged as N8YX and PA5COR's lots. At least I have some decent trees.

W5GA
04-07-2011, 02:58 PM
What band will it be for?

N8GAV
04-07-2011, 03:14 PM
What band will it be for?

160 thru 10

W5GA
04-07-2011, 03:25 PM
That's a whole lotta traps for one piece of wire. You'll also need to consider that an inverted vee on 160 is 235' or so long, needs a good bit of real estate. You could feed it with window line and use a balanced tuner and not worry about traps. For most, it's the real estate issue though.

N8GAV
04-07-2011, 04:31 PM
I have 3/4 of an acre, and I'm thinking of feeding it with 600 ohm twin feeders or maybe 450 ohm ladder line to my SA 2040, I changed out the 18 uh roller inductor and replaced it with a 28 uh one so I could get it to work on 160 with old antenna that I was using. Any thought's Russ?

W5GA
04-07-2011, 05:03 PM
You might take a look at this:
http://www.palstar.com/qstAT1500bal.pdf

Don't know if you run QRO or not, but if you do the built in balun (does it have one?) on your 2040 will probably give up on you.

W1GUH
04-07-2011, 05:20 PM
Or.....if you're really serious about "Good Old Stand By"....a Johnson Matchbox simply cannot be beat. The small ones go for < $100 if it's not "minty" and will probably be good for a lot more than what they're rated for. Or the the KW matchbox for when you get a 1KW DC input (or output) plate modulated BA on the air!

Also, homebrewing a link-coupled tuner is as close to trivial as a project can be.

But there's a flaw in your logic. It's foolhardy to put up a wire antenna in good weather. Everybody knows that it's been scientifically proven that the worse the weather, the better the antenna will work and the longer it will last. We're probably 2 months past peak antenna raising weather!

kd8dey
04-07-2011, 06:05 PM
OCF??

NQ6U
04-07-2011, 06:14 PM
Never mind...

N8GAV
04-07-2011, 07:00 PM
You might take a look at this:
http://www.palstar.com/qstAT1500bal.pdf

Don't know if you run QRO or not, but if you do the built in balun (does it have one?) on your 2040 will probably give up on you.


Or.....if you're really serious about "Good Old Stand By"....a Johnson Matchbox simply cannot be beat. The small ones go for < $100 if it's not "minty" and will probably be good for a lot more than what they're rated for. Or the the KW matchbox for when you get a 1KW DC input (or output) plate modulated BA on the air!

Also, homebrewing a link-coupled tuner is as close to trivial as a project can be.

But there's a flaw in your logic. It's foolhardy to put up a wire antenna in good weather. Everybody knows that it's been scientifically proven that the worse the weather, the better the antenna will work and the longer it will last. We're probably 2 months past peak antenna raising weather!

Balun is no problem has a 4:1 in 2040 and I have 1:1, 4:1, and 9:1 W2AU if I need one. Had to get my knee better before I started any antenna work this time I may lose 20 db but oh well :)

W1GUH
04-07-2011, 07:08 PM
Pity. Well, it'll last until good antenna weather is upon us again! :lol:

VE7DCW
04-08-2011, 12:05 AM
Now that the weather is breaking time for a new antenna since the dublet took a beating this winter. Thinking of an Inverted Vee an oldie but goodie and I have trees that would give me 65' height at center. What do you guys think worth it or not??

Hank ..... I've got 2 antennas up in the air at the moment a double Zep and my 20 meter inverted V made from good ol' 18 guage speaker wire....I was told just recently that my 20 meter inverted V and 100 watts from the Yaesu 101ZD was actually challenging Mr.Kooky and his "tube with Handles" in signal strength one afternoon last week ....... nope, you can't beat simplistic antennas :-D

73

KG4CGC
04-08-2011, 12:25 AM
Could someone draw and post a schematic of a double zepp please? Thanks.

kd8dey
04-08-2011, 12:56 AM
Could someone draw and post a schematic of a double zepp please? Thanks.
Isn't that made the same as a dipole EXCEPT 1 wavelength long and fed with ladder line instead of a balun/coax ?

PA5COR
04-08-2011, 02:58 AM
http://www.g3zps.com/Page4.htm

Just like my Inverted L antenna an oldie but working quite nice thank you ;)

W1GUH
04-08-2011, 11:40 AM
If you've got the room, a Lazy-H (http://www.hb9tpl.ch/4955.html) is great fun to play with. (Google-fu will turn up many more hits...I picked that one arbitrarily.) I had one where the elements were a double extended Zepp on 10 meters, & it performed well down to 40. It certainly had directivity (from the zepp)...switching between it and a 75m dipole (I had two tuners) demonstrated that.

Only problem was, I was too lazy (well it WAS a lazy-h!) to use a comp-ass, so instead of beaming Hawaii I wound up beaming Alaska!

The following is meant FYI about baluns....FWIW....

Tuners that pretend to be balanced by using a balun on the output will do OK, and probably do well; there's no doubt about that. But here's the thing. Baluns don't like mismatches -- that's when the losses go up, and when using an antenna for all bands you will have mismatches; the impedance will vary all over the map. That's beauty of balanced feedling -- the match at the anteann is of no concern at all since the feedline loss is practically negligible. But once you put a balun in there, it will eat "some" power.

Guess what I'm saying is, if you already have a "pretend " ;) balanced tuner, you're better off with balanced line than with coax. But if you're planning a new tuner (either bought or made) go for a link coupled tuner (I know, I know....but I LOVE Matchboxes!).

The other type of balanced tuner, which is basically two unbalanced tuners, one for each side of the feedling, and with a balun on the input is a good solution, too. That's the application where baluns are appropriate -- they won't see a mismatch.

Have fun!!!! Sure wish I had some RE to play with wires.

KA5PIU
04-08-2011, 11:45 AM
Hello.

Since I have started to "Meg" my antennas I have been very careful about not using trees.
http://www.sphere.bc.ca/test/megger.html
In fact, that cheap electric fence insulator simply will not cut it.
I now use the lowest current rated hi line insulators I can find, rated to at least 7.5kV.
Lightning protection is a critical part of it.
But the reduction in losses more than make up for it, over 12 dB of gain just by replacing insulators.
Old glass insulators of the type used for old telephone and telegraph lines are perfect but are getting hard to find and can get stolen.
Due to the 200 volt sealing voltage our old open wire telephone lines run hot.
Somebody was trying to steal one of the glass insulators and fell to his death a few years ago.
After that I decided to leave the 200 volts as is, this is the same scheme used for the old teletypes and in theory one could use it to superimpose a teletype over the same pair.
In fact, the DC supply is the same thing that would have been used by a teletype machine.
I put a bunch of RF chokes on the line and superimpose 160 meters at low power on it. ;) telephone and phone, all at the same time.
http://www.kadiak.org/tel/17-3.htm
I use repeating coils with a center tap like one would use for a phantom circuit but apply RF and only one pair.
The other side being ground.

W5GA
04-11-2011, 03:21 PM
Old glass insulators of the type used for old telephone and telegraph lines are perfect but are getting hard to find and can get stolen.
For those interested...you can still buy ceramic hot wire insulators at most any farm supply/feed store. Not as cheap as the plastic eggs, but they don't melt.

WØTKX
04-11-2011, 08:10 PM
One thing to remember about the Inverted Vee is as you go higher up in frequency from the "fundamental" you will get some freaky lobes that go straight up. Useful on lower frequencies, not so much on 10 meters. If the Vee is not terribly acute (more of a flat top), the effect is minimized, but you lose the effect of the vertical radiation and omni-directional characteristics.

Get a guest account on www.cebik.com and check out the extensive diagrams that show that.