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Author Topic: 43ft multiband vertical  (Read 46746 times)
K8JHR
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Posts: 29




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« Reply #90 on: November 23, 2008, 11:15:27 PM »

Ah... yes.... I get it now.  I was not rignorious in my reading and missed that small change -  small name change with a big impact on the result!

Thank you for the courtesy of explaining this. I did miss something.  And I agree with your estimation or assessment of the situation.

I wonder if they would swap yours out for a new one... or can you modify the one you have to work properly as did our friend, ES1TU ...?

=====  K8JHR  ====

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K0OD
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Posts: 3018




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« Reply #91 on: November 24, 2008, 08:54:08 AM »

I did the simple mod. Hard to tell whether my MBVE-1 is working better although it was certainly easy to snag Europeans on 40 CW in the Bulgarian DX test with 100 watts. 80 was still very tough.

Read more comments on this subject at:

http://www.eham.net/forums/TowerTalk/16020?page=2

AS has indeed changed their recommended matching device.
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K8JHR
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Posts: 29




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« Reply #92 on: November 25, 2008, 01:18:35 AM »

This whole ordeal has made me feel better about my purchase from DX Engineering.  I wonder how the guys at Array Solutions and Zero-Five could have gotten it so wrong?  It seems more than a typo, and has been on the site for quite a long time to be an administrative error.

I am thankful for all the input so many have put in here, also.

===  K8JHR  ===
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WA1RNE
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Posts: 1007




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« Reply #93 on: November 25, 2008, 10:52:25 AM »


 The UNUN is the right configuration compared to a balun, but either way, depending on the band of operation, the amount of decoupling (radials), etc. it relies on typical feedline lengths to present an impedance most autotuners can handle.

 Zero Five indicates in their installation notes that the SWR will be high in normal operation. They also recommend 1/2" line like LMR600 for long lengths and/or high power:

 From their web site:  http://www.zerofive-antennas.com/43ftvert.pdf

 COAX CHOICE

A good low loss coax should be used with this vertical. For runs up to 150 feet, Bury flex or LMR
400 works great. For longer runs or near-legal-limit operation use LMR 600 or ½ inch heliax.
Please remember that this antenna system is NOT resonant on any of the amateur bands. As a
result, the feed line is operating at a higher than normal SWR most of the time. This can cause
additional stress on the coax run especially under high-power conditions. Be sure to use a coaxial
cable heavy enough to carry the power you’ll be using plus an additional safety margin due to the
high SWR conditions."  


 ...and about the best feed method:

 A remote tuner or a matching transformer, what should I use? –
A remote antenna tuner installed at the base of the vertical provides the best match to the coaxial
cable and will reduce SWR and power losses in the cable. Unfortunately, if you’ll be using power
levels above 200 watts or so, the choice of rugged, weather resistant tuners is almost nonexistent.
Yes, you can use an automatic tuner built for indoor use outdoors if you install it in a
weather resistant housing but it really isn’t the ideal way to go.
Another solution for the high power problem is to use a matching transformer at the base of the
antenna and put the tuner in the ham station. If you already have a good tuner available, this
may be the best solution. There are a couple of problems though. The SWR on the coax back to
the station will be high and as a result there will be line losses and possibly heating in the coaxial
cable and matching transformer under full legal limit conditions. Problems with RF feedback into
the ham station are also a possibility too.


 Running 160 with this antenna will be a challenge to say the least:

  With 100' of 9913 or LMR400 and the 4:1 balun, your shack tuner will be dealing with an impedance of about 6 ohms which is considerably outside the range of most tuners. You could add some base loading which would make the tuners job easier but that essentially defeats the convenience of the autotuner.

 In my opinion, the best solution for 160-40 would be to remove the UNUN and install a homebrew L Network. It could be designed with relays to remotely select the needed inductance and a remote controlled air or vacuum variable. It's more complicated and isn't cheap, but it will not be dependent on the feedline to obtain a tunable load impedance and won't require expensive coax to run power and keep losses down.

 
 ...WA1RNE
 
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N3OX
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Posts: 8915


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« Reply #94 on: November 26, 2008, 01:56:13 PM »

"I wonder how the guys at Array Solutions and Zero-Five could have gotten it so wrong?"

I don't think they have all the blame in this. Even with a perfect 4:1 transformer, this is still an iffy antenna design, yet we've been grabbing them up for the last couple years and giving them five out of five eHam reviews even WITH the incorrect choice of a 4:1 voltage balun and the mediocre feed system choice.

Everyone was buying these things because everyone was saying they were wonderful.

Array Solutions and Zero-Five are businesses.  They were selling what people wanted.  It's clear they figured out their product would be better with a different transformer.   It's not like their original antenna was selling poorly because of poor performance.

But don't kid yourself that ANY antenna manufacturer is just selling what people want.  

Let's step back?  Why does everyone want a 43 footer with a 4:1 transformer anyway?

Honestly, what I think is happening is that right now, today, the skeptical holdouts are starting to buy 43 foot verticals with 4:1 transformers and finding they're either OK antennas or antennas with a problem.

73
Dan



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73,
Dan
http://www.n3ox.net

Monkey/silicon cyborg, beeping at rocks since 1995.
K0OD
Member

Posts: 3018




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« Reply #95 on: November 26, 2008, 04:45:35 PM »

Zerofive did figure out one thing that apparently eluded most old line antenna makers: There is a sizable market for taller verticals that hold out promise of good performance on the low bands.

Where is it written that verticals have to be less than 30 or so feet tall?

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N3OX
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Posts: 8915


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« Reply #96 on: November 27, 2008, 09:21:23 AM »

"Where is it written that verticals have to be less than 30 or so feet tall? "

Perhaps it's a secret message encoded in $200 or less worth of aluminum tubing and 70MPH winds.

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73,
Dan
http://www.n3ox.net

Monkey/silicon cyborg, beeping at rocks since 1995.
W5DXP
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Posts: 4436


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« Reply #97 on: December 01, 2008, 04:24:32 AM »

> K0OD wrote: Where is it written that verticals have to be less than 30 or so feet tall? <

When the length of the monopole gets to be much longer than 5/8WL, the radiation angles rise and power is wasted into outer space. Low angle radiation is what one wants for DX. 5/8WL on 15m is about 27.5 feet. 43ft is 5/8WL on 13.6 MHz limiting its effective upper frequency DX performance to 20m.
--
73, Cecil, w5dxp.com
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73, Cecil, w5dxp.com
K0OD
Member

Posts: 3018




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« Reply #98 on: December 01, 2008, 10:19:01 AM »

"Where is it written that verticals have to be less than..."

There must be a big market for purely low band verticals to augment triband yagis. The popular Butternut HF2V 40/80 vertical addressed that common situation. No matter how efficient a vertical is on the higher bands, a high dipole will probably be far better, plus quieter on receive.

A lot of hams have the erroneous notion that any vertical over about 25 feet must be mounted in massive concrete and supported by several sets of ugly guys.

Note that Zerofive has come out with a 50' version of their vertical for 30 meters and down.    
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N3OX
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Posts: 8915


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« Reply #99 on: December 03, 2008, 05:50:27 PM »

hundredth post! WHOO!
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73,
Dan
http://www.n3ox.net

Monkey/silicon cyborg, beeping at rocks since 1995.
KE7FXO
Member

Posts: 3




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« Reply #100 on: October 16, 2009, 04:49:41 AM »

I recently put up a Zero Five 43 footer. I haven't installed the radials yet, but am getting ready to. I didn't know about all the confusion about the baluns vs. unun's until I already had everything else put together.

I bought my antenna (and Array Solutions AS-200T balun) about a year and a half ago, before all this debate over the balun vs. unun really got going, and back then, it was the *BALun* (instead of the UNun) that was recommended by Tom (at Zero Five), and by the guys at Array Solutions, as we all know.

Now, here's my situation, and I am HOPING that it will make a difference, because I do NOT want to take apart my system, since I did everything (like waterproofing, etc...), as permanently as possible...

My installation is ELEVATED. Rooftop mounted, at about 20 feet. Since my radials are going to tuned for each band, that would make my antenna a relatively BALANCED load, at the frequencies I tune them for... Correct?

So, would the *BALun* be OK to use (even if it is a voltage balun), considering that I am using an unbalanced feed line (LMR-400) coax, and going into a BALANCED load?

Also, I went ahead and put a dozen of the proper torroids over my coax, just under the feedpoint, to block off any common mode currents coming back down the coax.

The antenna itself is isolated from ground on a non-metallic mast (bolted to the side of the eave), but I do have my coax going into an I.C.E. surge suppressor, which is heavily grounded at the base of the antenna mast. The feedline continues back to the shack, after that grounding point.
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K8JHR
Member

Posts: 29




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« Reply #101 on: October 16, 2009, 06:17:44 AM »

No, unfortunately, think it matters A LOT.   I have a 43 footer, myself,  and have used the DXE Balun and  DXE Un-Un, respectively.  

I followed the discussion on the Zero-Five /Array Solutions balun last year as it was happening, and talked to both Array Solutions and Zero-Five at Dayton this past Spring.  

1)   You MUST get the proper UN-UN from Array Solution. !!  - or - use the 4:1 current balun DXE sells  (I have both)  and each was analyzed by several of the experts involved in the Zero-Five / ArraySolutions flop, and both are acceptable designs.   Trying to cut corners by using the wrong balun, all because you do not want to undo your current installation, is a recipe for disappointment.    I understand your frustration or angst at having to change your installation, but I REALLY think it matters and you NEED to get the proper balun/un-un.   I have no doubt that DXE changed their design after that discussion was held - even though all the experts conceded their 4:1 current balun was a good design and did not suffer the same problems as the Array Solutions  voltage balun.   It was simply a mistake as to which balun to supply - just odd no one had caught it before then.  

2)  If you use the incorrect balun, you will not get acceptable results.  Period.   I really researched this when the guy on QRZ.com posted about his balun, and lots of great minds worked the matter over for a long time.  

3)   I DO NOT BELIEVE YOU CAN MAKE THE ANTENNA RESONANT ON ANY USEFUL HF FREQUENCY.   The whole point of the 43 footer is that IT IS NOT  resonant on ANY frequency  within the HF bands we use.  It is a compromise size that allows us to bludgeon the stick into submission by using a 4:1 Un-Un  (or properly designed 4:1 current balun) and a big, substantial outboard tuner (transmatch).   Reason I say this is the 43 foot element will not balance your tuned radials.   It will not be a proper length for any frequency in the ham bands, even though you are going to cut your radials for the bands of interest.  

OBSERVATION -  I am amazed you would consider a roof mounted 43 footer !  Good Luck.   I would not try it.

4)  You do not mention guy wires or ropes?   I would not put one of these 43 footers up in the air like that with out guying them.  I really worry about mounting it so high.   Did you  check with the guy who runs Zero-5 about this?   He is a swell guy and rather accessible - if not a bit eccentric (and quite a character!)  so I would be sure of the engineering before I put such a big stick that high up in the wind.  

5)   I strongly recommend GROUND MOUNTING WITH AT LEAST 30 radials and if possible double that.   If you make them up in the work shop before going outside, you can save time and properly crimp and solder the lugs onto the wire, and cut the wire to length.   I used typical lengths of about 40 feet, with some at 30 feet and some at 55 feet to accommodate the available distances in the yard after placing the stick in position.   This will not take that long.  I laid the first 30 in about two hours.   I added more, about five at at time, here and there during the next week, and IN TOTAL it took me no more than a 4 hour period to lay all 65 radials.   CUT THE GRASS CLOSE - LIKE REAL CLOSE before you lay the radials,  and then let the grass grow a bit long before you cut it.  Use plenty of staples to lay the wire down or you will lose some when cutting the grass the first time or two.  After a month, they will be down enough to use a riding mower for the duration of the mowing season.  TELL THE LAWN SERVICE GUY about them.   I had a sloper with 6 radials two summers ago, and he kept moving them to mow, so it took all summer for them to become lost in the thatch.   The were down safely about three weeks after I figured this out and convinced him he did not have to work that hard to curry my favor !  Jose aims to please !  

5)   The ferrite beads are OK, but I doubt they will do anything for you.  A properly designed Un-Un will serve to avoid unwanted feed line radiation - both DXE and ArraySolutions told me that.   On the other hand, I don't think they could cause any problem and may be helpful.  Couldn't hurt.  

Just MY take...  good luck.  

=================  K8JHR ==========================
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K8JHR
Member

Posts: 29




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« Reply #102 on: October 16, 2009, 06:17:50 AM »

No, unfortunately, think it matters A LOT.   I have a 43 footer, myself,  and have used the DXE Balun and  DXE Un-Un, respectively.  

I followed the discussion on the Zero-Five /Array Solutions balun last year as it was happening, and talked to both Array Solutions and Zero-Five at Dayton this past Spring.  

1)   You MUST get the proper UN-UN from Array Solution. !!  - or - use the 4:1 current balun DXE sells  (I have both)  and each was analyzed by several of the experts involved in the Zero-Five / ArraySolutions flop, and both are acceptable designs.   Trying to cut corners by using the wrong balun, all because you do not want to undo your current installation, is a recipe for disappointment.    I understand your frustration or angst at having to change your installation, but I REALLY think it matters and you NEED to get the proper balun/un-un.   I have no doubt that DXE changed their design after that discussion was held - even though all the experts conceded their 4:1 current balun was a good design and did not suffer the same problems as the Array Solutions  voltage balun.   It was simply a mistake as to which balun to supply - just odd no one had caught it before then.  

2)  If you use the incorrect balun, you will not get acceptable results.  Period.   I really researched this when the guy on QRZ.com posted about his balun, and lots of great minds worked the matter over for a long time.  

3)   I DO NOT BELIEVE YOU CAN MAKE THE ANTENNA RESONANT ON ANY USEFUL HF FREQUENCY.   The whole point of the 43 footer is that IT IS NOT  resonant on ANY frequency  within the HF bands we use.  It is a compromise size that allows us to bludgeon the stick into submission by using a 4:1 Un-Un  (or properly designed 4:1 current balun) and a big, substantial outboard tuner (transmatch).   Reason I say this is the 43 foot element will not balance your tuned radials.   It will not be a proper length for any frequency in the ham bands, even though you are going to cut your radials for the bands of interest.  

OBSERVATION -  I am amazed you would consider a roof mounted 43 footer !  Good Luck.   I would not try it.

4)  You do not mention guy wires or ropes?   I would not put one of these 43 footers up in the air like that with out guying them.  I really worry about mounting it so high.   Did you  check with the guy who runs Zero-5 about this?   He is a swell guy and rather accessible - if not a bit eccentric (and quite a character!)  so I would be sure of the engineering before I put such a big stick that high up in the wind.  

5)   I strongly recommend GROUND MOUNTING WITH AT LEAST 30 radials and if possible double that.   If you make them up in the work shop before going outside, you can save time and properly crimp and solder the lugs onto the wire, and cut the wire to length.   I used typical lengths of about 40 feet, with some at 30 feet and some at 55 feet to accommodate the available distances in the yard after placing the stick in position.   This will not take that long.  I laid the first 30 in about two hours.   I added more, about five at at time, here and there during the next week, and IN TOTAL it took me no more than a 4 hour period to lay all 65 radials.   CUT THE GRASS CLOSE - LIKE REAL CLOSE before you lay the radials,  and then let the grass grow a bit long before you cut it.  Use plenty of staples to lay the wire down or you will lose some when cutting the grass the first time or two.  After a month, they will be down enough to use a riding mower for the duration of the mowing season.  TELL THE LAWN SERVICE GUY about them.   I had a sloper with 6 radials two summers ago, and he kept moving them to mow, so it took all summer for them to become lost in the thatch.   The were down safely about three weeks after I figured this out and convinced him he did not have to work that hard to curry my favor !  Jose aims to please !  

5)   The ferrite beads are OK, but I doubt they will do anything for you.  A properly designed Un-Un will serve to avoid unwanted feed line radiation - both DXE and ArraySolutions told me that.   On the other hand, I don't think they could cause any problem and may be helpful.  Couldn't hurt.  

Just MY take...  good luck.  

=================  K8JHR ==========================
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W9OY
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« Reply #103 on: October 16, 2009, 07:43:50 AM »

I put up a wire version of this antenna, and have tested it using the websdr.org receivers.  Websdr when I did my tests had a 10 band version of their receiver operational.  I have compared this 45ft wire version against my full size vertical antennas on 80 40 30 and 20.  On 80 I have 1/4 wave, 1/2 wave on 40, 5/8 on 30 and 1/2 wave on 20.  

Note the websdr.org receivers are calibrated in dBm and use software such that the meter readout is truly from a strait line and not a curve.  IN other words there is no S meter compression.

My set up uses an auto tuner (MFJ 929) at the antenna base as opposed to a transformer and only has a few radials.  As such on a 4500 mile path into Europe this antenna was fair compared to the full size down by about 6dB on the average.  On the rest of the bands tested there was hardly any difference at the distant receiver.  The 45 footer never surpassed the full sized optimized antennas over a well defined ground, but it was generally not down by more than 3dB and perfectly Q5 into Europe using 100 W. I could probably make up part of that difference by improving the radial system.  The bottom line is its not as bad as some say and its not as good as others say.  If I was in a stealth situation I would definitely consider this antenna over something in the attic or around the eaves.  

Here is a shot of the setup

http://w9oy-sdr.blogspot.com/2009/09/43ft-vert.html

If I was going to use one of the Zerofive antennas I would probably electrically extend its length using a T format for 160 80 and 40, and then hang a dipole off the guy wires for the higher bands

73  W9OY
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W8JI
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« Reply #104 on: October 16, 2009, 09:35:01 AM »

Where is the data for your signal level comparisons?
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