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KG4CGC
09-21-2010, 11:20 PM
... 100 feet of LMR 400, 60 feet of 450 ohm window line, 500 feet+/- of 10 gauge insulated copper wire and a 1.5KW 1:1 current balun?
Possibly 160m + 80/40m and possible 20m but should be centered around 80/40m.
Got some trees, some rope plus 100 feet of UV Dacron rope. Trees are 100 feet tall in some spots.
Should I use the window line for a folded dipole @20/40 and the 10ga wire fore a 160/80 connected to the same point on the balun?

I'm all ears.

PS, have 20 feet of heavy duty tv mast on the ground, can get about 10 or 20 more. One mast already up at 36 feet that I could also use to support the center but mast wise, can't go over 40 feet without getting into some really serious support stuff.

NQ6U
09-21-2010, 11:45 PM
I'd suggest an inverted L antenna for 160 m, but that's just me.

BTW, did you get those photos I sent?

KG4CGC
09-22-2010, 12:26 AM
Ah yes I did. Thank you berry much. No worries, I use a crappy cell phone sometimes and have pulled miracles out of my miracle puller.

KG4CGC
09-22-2010, 12:27 AM
I'd suggest an inverted L antenna for 160 m, but that's just me.


Would it change for the worse if it came out more like an inverted J?

NQ6U
09-22-2010, 12:53 AM
Ah yes I did. Thank you berry much. No worries, I use a crappy cell phone sometimes and have pulled miracles out of my miracle puller.

Glad you got 'em. Some pretty nice items, you ought to be able to use at least some of them.

NQ6U
09-22-2010, 12:57 AM
Would it change for the worse if it came out more like an inverted J?

Hard to say, I am certainly no great expert.

Give it a try, you never know about stuff like that. I made a 6m antenna using copper pipe and an old water heater, it works great, and that's what makes ham radio a fun hobby

KG4CGC
09-22-2010, 01:14 AM
Well once it goes up, it doesn't come back down except for catastrophic failure. I've considered using a pulley system at 4 points to raise and lower it. That would mean counter weights at each of the 4 points.

KG4CGC
09-23-2010, 09:25 PM
Bump up for attention.
Still listening.

K7SGJ
09-23-2010, 09:51 PM
Ask over at the other site. They know everything. Just askem. You'll even get formulas, smith charts, drawings, and all kinds of shit you didn't ask for. And since the first is smarter than the second, ad pukem, they'll be at each others throat in a heart beat.

KG4CGC
09-24-2010, 01:17 AM
I kind of agree but lately I've been going more Zen. I'd rather ask what the happy people think.

N2CHX
09-24-2010, 07:33 AM
Well once it goes up, it doesn't come back down except for catastrophic failure. I've considered using a pulley system at 4 points to raise and lower it. That would mean counter weights at each of the 4 points.

I always make my antenna's so they can come down and go back up easily. You have some pretty interesting stuff to work with. Might I suggest an end-fed Zepp? Good performing antenna and it seems it would maybe alleviate your not having the room to put up a proper inverted L. It seems you already have all the ingredients you need to build one and it might work out quite nicely for you as long as you have a good ground to work with. You will also need a balun or a tuner with a balanced output. Design it for the band you use most and it should also tune and work well on other bands.


I once built an end-fed Zepp to get an AM station back on the air after a tower failure. It worked quite well.

W2NAP
09-24-2010, 08:17 AM
I once built an end-fed Zepp to get an AM station back on the air after a tower failure. It worked quite well.

got pics?

K7SGJ
09-24-2010, 08:48 AM
I kind of agree but lately I've been going more Zen. I'd rather ask what the happy people think.

Problem is there are no happy people left over there. The've all come to de Island.

N2CHX
09-24-2010, 11:03 AM
got pics?

Somewhere on a disk, yes. This was about eight years ago. I have video of the tower coming down too. Somewhere.

KJ3N
09-24-2010, 01:21 PM
Just some random thoughts:

If I have 500 feet of wire, I'm making more than 1 antenna.

You mention some rather tall trees, but you don't give any dimensions as far as distance between trees. Also, what's the orientation of these trees? N-S, E-W, something else?

What bands do want this antenna to work on?

KG4CGC
09-24-2010, 01:50 PM
One leg will run E to W and then turn 90 degrees an finish out N to S. The other leg may only run N to S but there are other possibilities. It could go W to E and then turn N to S.
I could conceivably put up enough wire for 160m but that is only a consideration. It'd like to center it at 40m and overlap to 80m with possible overlap to 20m.
I intend to use a completely different set up for 17m. A simple dipole, sloper, etc. I have an A-99 that works 10m through 15m like nobodies business and I switch back and forth between the 80m dipole and the A-99 for 20m depending on which one pulls in the signal better.
The current 80m dipole that some of you guys have heard me on will be relegated to receive only status after the higher new ant goes up.

W2NAP
09-24-2010, 06:15 PM
Somewhere on a disk, yes. This was about eight years ago. I have video of the tower coming down too. Somewhere.

tower coming down. that should be on youtube!

N2CHX
09-24-2010, 06:28 PM
tower coming down. that should be on youtube!

It was recorded on VHS-C. I could dub it into an mpeg but I'd have to dig up the tape first.

W2NAP
09-25-2010, 02:21 AM
id still love to see the AM station running on a zep.

what was the power level 1KW?

W3MIV
09-29-2010, 10:33 AM
I am limited for space, occupying only a 1/3-acre lot and being surrounded by neighborhood nazis for whom the sight of any wire that suggests an antenna is anathema. :(

I had a 100' flat top dipole strung in my maples and fed by about 30' or so of 300 Ω window line (cut-n-fit for minimal reflections with analyzer). It gave me excellent performance on 80 through 10, and that despite being only a bit more than twenty-four feets off the ground and buried in lots of maple branches. I do have a very comprehensive system of ground radials cut to the bands (roughly) that were originally installed with ground rods for the AH4 installation, though that tuner and its antenna is no longer being used. The few TB contacts I have in my log were garnered with the ICOM AH4 antenna tuner located on the outside wall feeding a 90' wire. Unfortunately, that lash-up resulted in bizarre RF effects -- especially touch lights in the kitchen, which cycled through the dimmer's range with every key; at night the kitchen might look like a naval bridge with a yeoman sending by lamp. XYL was NOT a happy camper. Hence, the dipole. With the simple flat-top I collected cards from Asia through Eastern Russia (incl Australia, Hong Kong, Taiwan, Japan, Iceland, most of Europe, east and west, including Romania, also Peter I Island and a host of other pile ups -- all without using the AL80B, which is more of a PITA to tune quickly than it is worth). I used to log them fastidiously on both computer and paper log, also uploading them to LOTW and EQSL, but have not logged on to either in more than two years. I have not been on HF for that same period of time.

I am now in the process of reinstalling the same design since the last one was brought to the ground by a neighbor's tree falling into my yard. Reusing the same Ten-Tec "Acrobat" center insulator; it is an excellent fixture and very durable. Cost me ten bucks. Twelve gauge insulated wire for the legs, and the window line (which is 14ga copper stranded) to a 1:1 current balun just outside the house. About 25' or so of coax to the IC756P3 and the MFJ993B auto-tuner, which worked flawlessly for me, tuning instantly wherever I wandered on the bands.

If ever I finish the rigging of my leafy masts, I shall announce it with a holler.

The antenna design, BTW, is Walt Maxwell's basic dipole. His book, "Reflections" is a must-have in any ham library. Busts many of the "SWR" myths that plague many amateur minds.

I guess what I am rambling on about is that I am a fan of simple wire in the air. Before too much longer, I shall essay to prove it.

KJ3N
09-29-2010, 02:28 PM
I guess what I am rambling on about is that I am a fan of simple wire in the air. Before too much longer, I shall essay to prove it.

I prove it every time I'm on the air, Albi. Ask anyone here who has worked me. ;)

NQ6U
09-29-2010, 02:45 PM
The only HF antennas I've ever used were wire antennas. I have a trio of home-brew J-poles for 2m, 6m and 220 MHz as well a Cushcraft 6m beam I bought used for fifty bucks but everything else is wire.

KG4CGC
10-11-2010, 12:05 PM
Add another 200' to the equation as I picked up more window line this weekend.

WØTKX
10-11-2010, 02:17 PM
You have a lot of space... how about a big multiband loop and a vertical combo?

KG4CGC
10-11-2010, 10:53 PM
Thanks for the inputs :)

W3MIV
10-12-2010, 08:42 AM
Why not just string some wire as high as you can and use a ladder to feed it? Do something long enough to work 75 and up. A cloud-warmer like I have will not reach out very far on 75, but it covers most of the East Coast at night, and you are entering the only time of year when it is really usable.

Git off'n yer butt an' chuck somethin' up!

KJ3N
10-12-2010, 08:58 AM
.... and you are entering the only time of year when it is really usable.

75m is usable almost the entire year. Granted the noise is higher during the summer, but I've have DX contacts in June and August.


Git off'n yer butt an' chuck somethin' up!

Agreed.

KG4CGC
10-14-2010, 11:19 PM
OK. I wanted to know what yoos guyz thought would work best wit wirz.
I could effectively put up a 160m doublet folded dipole since acquiring more window line. It would be hung all funny though.
I'm looking at a dipole for 80 and a folded dipole for 40 attached to the same point on a 1:1 current balun.
Now, could I go with an OCF on 160 with a folded dipole for 40 attached to the same point and expect it to work fine business on 80?

I'm painting Friday and later I have to do the GF birthday thing and I may have to paint some on Saturday but the weather for the next few days should be antenna erection friendly.

W3MIV
10-15-2010, 04:34 AM
A matchbox is your friend. An 80m dipole will work on 40, and also on 15; with a transmatch, it will work 80 thru ten well. You can easily get away with as little as 100 feet of wire fed with ladder line (attached to your 1:1 current balun at the coax). That is about 3/8 wave on 80. With a decent matchbox, it will work all the bands, including seventeen and thirty. It is what I am using right now, and it works.

Top Band takes some real estate, and you gotta get it up high to be effective. NVIS will work OK for short-range contacts, but to go really far you need to be well up in the air.

KJ3N
10-15-2010, 08:53 AM
Top Band takes some real estate, and you gotta get it up high to be effective. NVIS will work OK for short-range contacts, but to go really far you need to be well up in the air.

Think Marconi antenna with lots of radials. :whistle:

N8YX
10-15-2010, 09:36 AM
Think Marconi antenna with lots of radials. :whistle:
That, or 125ft of Rohn 45 with a capacitance hat atop it.

Shunt-feeding the tower allows one to drape other antennas over the structure without drastically compromising the tuning and it also permits the structure to be DC-grounded.

KJ3N
10-15-2010, 12:26 PM
Think Marconi antenna with lots of radials. :whistle:
That, or 125ft of Rohn 45 with a capacitance hat atop it.

Shunt-feeding the tower allows one to drape other antennas over the structure without drastically compromising the tuning and it also permits the structure to be DC-grounded.

The Marconi is a lot cheaper, as long as you have trees. ;)

N8YX
10-15-2010, 02:08 PM
The Marconi is a lot cheaper, as long as you have trees. ;)
True, and if I were going to erect a wire vertical I'd be tempted to build something like a cage monopole with, say, 12" sides. Its top hat would consist of at least two 20' wires run from the apex and used as part of the support system.

You could series-feed this one and use a remote tuning network as the base.

I have such a contraption. It was built by Cubic (Oceanside, CA) for use with the commercial/military versions of their Astro line. Completely waterproof and remote-controllable via the transceiver.

Might be an interesting set-up for future use. I would rather connect their S1000 HF amp to that control port...IF I could find one.

kd8dey
10-15-2010, 02:40 PM
1005/f
1005/1.8= 558.3333333333333333333333333333333333333333333333 333333 feet so if your 500+/- will handle it you could do a 160m loop providing you have enough space and feed it with the ladder line to do the multi band thingie.

or if your not into the 160 crowd you could always do 80m (about 288 feet) using the ladder line for a matching stub (making it single banded) with over 200 feet of wire left over to play with along with the balun..........endless (almost) possibilities :)
or use the LMR-400 to redo your VHF/UHF vertical.......:)

NQ6U
10-15-2010, 02:47 PM
I have such a contraption. It was built by Cubic (Oceanside, CA) for use with the commercial/military versions of their Astro line.

For anyone who doesn't know, Cubic is the company which bought the Swan line of ham gear. I have an old Cubic (Swan) ST-3B antenna tuner than I still use every time I'm in my shack.

N8YX
10-15-2010, 04:08 PM
For anyone who doesn't know, Cubic is the company which bought the Swan line of ham gear. I have an old Cubic (Swan) ST-3B antenna tuner than I still use every time I'm in my shack.
I probably shouldn't hijack this thread...but...

Unless Rick Jacinth has somehow beat me out, I have in my possession the largest Cubic amateur gear collection on the planet. Some solid-state Swan stuff as well...which Cubic later re-branded. The Astro line is but one example.

ST-3B?

I have the 3...3B...3C (commercial model).

One of 20 "Cubic Kilowatt" rack-mount setups which were built. Included is an Astro-150R, PSU-7R, FP-7, ST-2R and a 1500ZR amp. I know where another is residing and am first in line to buy it. These cost north of $8k in 1982 dollars, or so I'm told.

Three Astro-DR "suitcase" setups. Two of these are complete with PSU-8s, battery pack/conditioners, ST-5 antenna tuners and all issued peripherals.

So many 150 and 102/103 series Astros that I've lost count. Tuners, PSUs and other peripherals included for each. Both amateur and commercial flavors. The 150 "C" commercial stuff covers some of the WARC bands, which the amateur versions did not.

2 1500ZA amplifiers. One is sitting in my shack at the moment, connected to my 7-line Drakes. It's the functional equivalent of an SB-200.

Etc.

Most was obtained broken and restored.

When working they're rugged as hell. The Astro 103 - when equipped with the 400hz CW filter - is one of the best rigs I've ever used on CW.

W5GA
10-15-2010, 11:58 PM
But, will any of them stay on frequency?

N8YX
10-16-2010, 06:33 AM
But, will any of them stay on frequency?
When they're properly aligned (the voltage regulator adjustment being the most critical) and from a cold start, the Astro 10x series will drift ~200hz before settling down. If you change bands, a similar amount of drift will be experienced.

After that they're almost as stable as a synthesized rig. Better than my 7-line Drakes and 820 series Kenwoods.

The 15x series will drift a total of 75hz after power-on then hold frequency indefinitely. Which is understandable because both oscillators used in their PLL chain are crystal reference.

The Astro-DR series simply will not drift. They incorporated a TCXO, which is a two-edged sword: The PLL divider chain is 4000 series CMOS and CMOS does not like hot environs. Thus, one of mine is due for a PLL rebuild...:angry:

N1BHH
10-17-2010, 05:28 PM
An Off Center Fed antenna with one leg of 90 feet and one of 180 feet will work well, fed with coax via a 4:1 or 6:1 balun will work very well. Double the length of each leg and you'll get very good coverage up through 160 meters. I may soon be building the 8 band variety using one or the other balun and fed with coax for my as yet purchased new HF rig. I have the wire, just waiting for the baluns and I'll be ready come the day to fire it up. I have done much research on it and this looks promising. Take a look at this page: http://www.buckscom.com/windom.htm

W3MIV
10-18-2010, 06:12 AM
One leg of 180' and the other of 360' takes up most of my surrounding neighbors' yards. Don't think I would be able to hide it well enough. :shifty:

W1GUH
10-20-2010, 11:36 AM
160 m dipole, fed with the ladder line and coupled with a matchbox you pick up at the next hamfest. Maybe you can trade the balun for it.

NQ6U
10-20-2010, 11:41 AM
Fuck all that other stuff--just build an isotropic radiator and be done with it.

W3MIV
10-20-2010, 11:45 AM
Fuck all that other stuff--just build an isotropic radiator and be done with it.

I built one, but I forgot to attach the transmission line and now I can no longer find it.

KG4CGC
10-20-2010, 11:53 AM
160 m dipole, fed with the ladder line and coupled with a matchbox you pick up at the next hamfest. Maybe you can trade the balun for it.
I do have one of those Yazoo Tenna Toonurs with a connection for balanced line. Add to the equation, 90' of 300 twinlead, probably to be used on the ends to make up for short footage of the windowline.

Just went over my stock of rope. I need to get more. Although I only need 100' sections to hold the wire in place, it takes a 200' section to get the job done. 3 points will require 600'. The trees are right and I just mowed the lawn for the last time this year. (did not forget the Stabil™)

W3MIV
10-20-2010, 03:21 PM
...I just mowed the lawn for the last time this year.


We'll see about that.

NQ6U
10-20-2010, 03:24 PM
Where I live, it's not uncommon to have to mow the lawn in freakin' February.

KG4CGC
10-20-2010, 06:05 PM
We'll see about that.
Unless we start hitting 80's consistently and get some serious regular rain, it will not grow anymore until Spring. Yer talkin' to a 42 year resident. :)

W1GUH
10-25-2010, 10:45 AM
Hold the phone. Sounds like with all the room you could do a rhombic or vee-beam? If so, screw everything else and do that!

KG4CGC
10-26-2010, 03:54 AM
125 linear feet from the main support mast east to west. 80m 40m fan dipole peaking at 80 feet in height at the end of the wire. I will have to get creative with the other half of the dipole. It will probably run north south for 36 feet then turn southwest for another 36' and maybe I don't know what after that.

Does this a folded dipole make for 160m? 125.5 feet west with 450 ohm windowline then capped with a 125.5 section of windowline in folded dipole fashion. Halfwave feedline, halfwave of folded dipole. It will reach a peak height of near 85 feet. The folded dipole section will probably droop in the north and south direction.

Next will be a simple vertical for 15/17m.

KG4CGC
10-26-2010, 03:58 AM
Hold the phone. Sounds like with all the room you could do a rhombic or vee-beam? If so, screw everything else and do that!
It would be great if I could run some wire in the front yard. The big lot next door belongs to the neighbors so, no wire in that yard.

W1GUH
10-26-2010, 10:54 AM
I've heard good things about folded dipoles made with ladder line. Go for it.

KG4CGC
10-26-2010, 12:24 PM
OK. Let's look at the numbers for the folded dipole for 160m. 125.5 + 125.5 while theoretically is a half wavelength when added together, will it resonate the way I hope it will in this configuration?

KJ3N
10-26-2010, 12:48 PM
..... will it resonate the way I hope it will in this configuration?

Resonance is over-rated.

Get as much wire as you can fit in the space allotted, feed it with ladder line, and put the fscking thing up. You're dragging this out far too much, IMO.

To paraphrase Voltaire, "Don't let perfect be the enemy of good enough."

KG4CGC
10-26-2010, 12:58 PM
There is rope on the trees! I'm making progress!
Dragging it out? Yeah, I have some of those messed up head characteristics where I can keep running the same idea in my head while making slight changes and looking at the outcome but, the proper outcome depends on the proper input. It keeps me in dopamine.

W1GUH
10-26-2010, 12:59 PM
Resonance is over-rated.

Get as much wire as you can fit in the space allotted, feed it with ladder line, and put the fscking thing up. You're dragging this out far too much, IMO.

To paraphrase Voltaire, "Don't let perfect be the enemy of good enough."

Complete agreement with that! Just get it up. Not only does "resonance" mean diddly when you're feeding with balanced line, even with a "resonant" dipole fed with coax you can never predict the length from formulas, so you're gonna have to prune it anyway. Just make sure you make it too long to start with.

KG4CGC
10-26-2010, 01:02 PM
OK. Like I said OTA, by the end of the week.

W1GUH
10-26-2010, 01:11 PM
The only good reason to delay putting up an antenna is to wait for bad enough wx. It's a known, proven scientific fact that antennas that are put up in the dead of winter, preferably during an ice storm will work much, much better and last much, much longer than those put up in warm dry wx.

NQ6U
10-26-2010, 01:13 PM
It's been my experience that scheduling a day to put up an antenna, especially if you've asked friends to come over to help, will inevitably bring on inclement weather.

KG4CGC
10-26-2010, 02:16 PM
Tis easier to pull kinks and knots through bare branches with a little wet on them than full foliage. I was approaching the limits of 30# test pulling the rope back through. LOL!
One of the reasons I've spent so much time thinking about this is because it will be the biggest wire antenna project for me to date, as well as the highest.
8' surf rod has been much more successful for me than the slingshot of yore!

W3MIV
10-27-2010, 12:43 PM
I have a good recipe for red drum if you come across any.

KG4CGC
10-27-2010, 12:53 PM
I have a good recipe for red drum if you come across any.
Got a "kids fishing for squirrels" story if you want to hear it. A little sad though, for the squirrel.
Rain past three days here. Thursday is going to be mast drop day.

K7SGJ
10-27-2010, 12:56 PM
Red Drum? I thought that was a medical condition that went with beer nuts or cotton balls.

KG4CGC
11-02-2010, 06:26 PM
Update: I've managed to bend two 10' sections of heavy duty, thick wall antenna mast.
Plan B: I have 2 more 10' sections and a 10' section of 1.75" galvanized steel water pipe. I'm going to slide the sections into the steel pipe and put it up with only a device to raise and lower the wire antenna and balun. Like a flag pole.
I think part of my problem today was the weight of the wire and the fact that the coax is inside the mast tubes. I'll raise the section inside the galvanized tube once it is up. A little grunt should get it done. This will diminish about 8 feet of the overall original height that I started with. Whatever right?

An addendum: The wire, I thought for some strange reason that I had 500' of 10 gauge wire. Well, it is actually 250' of 8ga. Wow, right?
I've had it for years and was saving it for marriage.

N5RLR
11-02-2010, 09:34 PM
Red Drum? I thought that was a medical condition that went with beer nuts or cotton balls.
Or from watching "The Shining" [click] (http://en.wikipedia.org/wiki/The_Shining_%28film%29) too many times. :mrgreen:

KG4CGC
11-09-2010, 11:36 PM
Well call me stupid but it makes sense now. My plans for an 80m ant turned out to be a 160. I don't know if that's good or bad but I'll leave it as is for a while. Tomorrow I'll measure out the window line and check the coax going to the 10m ant. I think the center conductor (or something) broke at the ant connector.

http://i25.photobucket.com/albums/c79/bebop5/AL2N%20High%20Point%20NC%20feb%2015%202009/af8fac23.jpg

N2NH
11-10-2010, 01:24 AM
http://i54.tinypic.com/54vybt.jpg

Hmmm... something about that image that I really like Paul... ;)

NQ6U
11-10-2010, 02:50 AM
Well call me stupid but it makes sense now. My plans for an 80m ant turned out to be a 160. I don't know if that's good or bad but I'll leave it as is for a while.

Charles, you should be able to tune up that antenna for 80m just fine, although the pattern might not be as good as you'd like. Do you have a field strength meter to check it out? If you don't like the pattern you can always try putting in a pair of traps.

W6EM
11-11-2010, 10:59 AM
160 is one of the HF bands that has such a wide bandwidth that the useful wire antenna bandwidth is only about 100kHz or so.

I use a 1/4 wave shorted stub at the feed point on mine and it gives me about 200kHz or so of relatively flat bandwidth. Easy and cheap to make out of TV twin lead with a 259B analyzer. Line impedance doesn't matter much since it's infinite at the design frequency with a shorted stub. The stub appears inductive as you go down in frequency and capacitative as you go up. Artificially lengthens and shortens your antenna accordingly. And, you can just let the stub dangle in the breeze.

KG4CGC
11-11-2010, 11:49 AM
Ah, about dangling in the breeze, that's on Saturday nights!
The original wire I had up is still louder on most bands except 160. It is even louder than the 160m ant on AMBCB.
I need to test these some time with a willing Island participant.

Yesterday I took down the 10m ant and saw where the outer jacket of the cable slipped about a eighth of an inch. It looked the most suspect as I tested for continuity and shorts and weird impedances. I cut off that end and tested it again and the problem was solved so I got out the torch and removed the old end and cleaned and prepped it for remounting. While I had everything down and apart, I went ahead and "refreshed" the other PL-259. Everything went back together and works fine business. I am considering raising this ant a few more feet as the present coax will allow.

Today I'm going to see what I can do with all the 450Ω window line. (doublet folded dipole configuration) It's going to have to go over the black walnut tree and I suppose the dipole configuration will have to droop. I really want this one to be best on 80m. I want it to hear better than the wire I've been using on 80 because if that is the best I can do with wire on 80 then I am really confused LOL! (and I am)