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KI6USW
01-01-2009, 02:57 AM
Hey Folks:

Went down to Ham Radio Outlet today and bought my first HAM rig.
It's an Icom IC 718. I also bought a LDG Z-100 that also plugs right in the back of the radio for power and an internal feed/switch.
Sweet!

They also had a $50 rebate. So the price was $559+tax-$50 mail-in rebate for the total out-of-pocket price for a new Icom and a new HAM.
Did you think I did all right?

I don't want to get a dipole. Because, although I have a house I don't have the space to stretch it out or do a "V' out of it either. So, I need to get a really decent Vertical antenna. Also, I want to reach as much band as I can, even if it is just for listening at this point. I hold a Tech license, and I plan to get my General license this year. So I need a radio that work for me as I listen. So what is the best for the $300 range?
Thanks for all replies ahead of time!

NE3R
01-01-2009, 03:08 AM
Just about any vertical will do. It sounds like you are looking for something like the 6BTV, Gap Challenger DX, or the HY-Tower Jr. There are many more.

The thing with verticals is, they radiate equally poorly in all directions! I use a simple 20 meter vertical for the high bands. And random wires for the low bands. You'll want lots of radials, as many radials as you can put down, and as long as you can make them :).

73 de Joseph Durnal NE3R

KI6USW
01-01-2009, 03:24 AM
Do they make a center coil or top load coil for these frequencies? Or doesn't that type of design work, or is it impractical?

N6ATA
01-01-2009, 04:29 AM
I started with the same setup last winter. I had poor success with a G5RV so I jumped on a 5BTV, roof mounted with elevated radials. It has landed 12 countries, including South Africa, and 47 states.

Can you roof or ground mount?

My friend in Indio has a Cushcraft ground mounted. He swears my that thing. And, its right next to his mobile home.

Good luck!

KI6USW
01-01-2009, 04:37 AM
I started with the same setup last winter. I had poor success with a G5RV so I jumped on a 5BTV, roof mounted with elevated radials. It has landed 12 countries, including South Africa, and 47 states.
Can you roof or ground mount?
My friend in Indio has a Cushcraft ground mounted. He swears my that thing. And, its right next to his mobile home.
Good luck!]

I was hoping to roof mount the antenna on the chimney; but I guess that idea is right out. One must understand, that my radio knowledge is better than CB radio - but not by a whole lot better than.
Is the 5BVT a dipole? You got me...
What model of Cushcraft is it? Details? Thanks!

WD5ABC
01-01-2009, 04:55 AM
]

I was hoping to roof mount the antenna on the chimney; but I guess that idea is right out. One must understand, that my radio knowledge is better than CB radio - but not by a whole lot better than.
Is the 5BVT a dipole? You got me...
What model of Cushcraft is it? Details? Thanks!

If you have a good strong chimney mount, it can work. Make the bottom of the vertical even with the top of the chimney and put out a couple of radials for each band you want to work and it will be great. An elevated vertical doesn't need as many radials but you need to make them resonant for each band. On the ground making them resonant doesn't do anything for you. If you just want to listen, just put the antenna up and add radials later as you have time.

Mount the vertical to a short mast with a couple of good strong chimney brackets, the kind with a stainless strap that goes around the chimney. Don't forget to ground the mast to a good 8' ground rod, it's going to be a big lightning rod up there.

I believe the 5BTV is a Hustler antenna, I have an old 4BTV that I've had forever, ground mounted with radials it works fine. Not as good as my old tribander at 60' but it doesn't make me worry when a hurricane comes through either.

73,
Kerry, WD5ABC

N6ATA
01-01-2009, 05:41 AM
It is a vertical. I have it mounted on the chimney with 2 radials per band. It takes a while to tune, but its a good starter. A butternut vert is better, but cost more.

The cushcraft my friend has is no longer made. It is multiband from 6 to 40. It has a ground plane "Umbrella" at the base instead of various radials. He's also throwing 600 watts.....the big cheater!

Have you looked into the mfj 1775? Im thinking about trying it with a TV rotor. Verticals are good when you have limits, but noisy as heck. the 718 doesnt filter too well. I recently upgraded to a 756 Pro2 and man, what a difference. I think i can make the 5BTV work a while longer now!

KI6USW
01-01-2009, 05:48 AM
So, it's between the Hustler and the Cushcraft.
Which one has better gain?

Since the IC 718 is a noisey radio; are there any filters that will help that out?
Or should I hunt down a radio mod for it?
(eg: mod that uses change/increase capacitance in the filter circuit?)

N6ATA
01-01-2009, 06:34 AM
So, it's between the Hustler and the Cushcraft.
Which one has better gain?

Since the IC 718 is a noisey radio; are there any filters that will help that out?
Or should I hunt down a radio mod for it?
(eg: mod that uses change/increase capacitance in the filter circuit?)

This is just my personal opinion, but i have learned that almost any antenna has the opportunity to be great. It all has to do with how well you install and consider all of the factors involved. Do you have your required ARRL antenna handbook? Get it for reference and read it, even if you dont understand it....It will be one of your best tools....besides QRZ!

But a Butternut would be my first choice

The 718 is a great starter radio. I have had the best season with it, and i will keep it as backup. You can buy the filters and make it better...or save the money for a good used 745 pro or Yaesu or Kenwood, etc. You get my point. Unless you plan on returning the 718, just use it and learn how to get the most out of it. Then, upgrade. You will really enjoy it.

KG4GYS
01-01-2009, 06:37 AM
Hi!!

Don't try and modify the 718. Get use to using the attenuator (ATT). I use a 718 in an absolutely terrible antenna situation. Once you get used to playing with the ATT, the DSP and RF gain combination's, you'll be fine.

I never really appreciated how effective attenuation could be until I moved to this QTH. For example, right now I'm listening on 3.944. Without ATT, the noise is S8. With ATT it drops to an S2. The signal I'm listening to with ATT is S7 over an S2 noise level. Without ATT the signal to noise ratio is almost a draw.

Good luck with the vertical!! At my last QTH, I used a simple 20 meter 1/4 wave ground mounted Home Depot special (aluminum tubing mounted on a Christmas tree stand) with about 15 random length radials on the ground. I worked over 25 countries and maybe 35 states back in late '06 to summer '07 with that antenna.

73's
Eric

KI6USW
01-01-2009, 07:02 AM
What about the GAP Challenger DX Engineering, or the MFJ-2990?
The GAP Challenger feeds coax like a vertical dipole. IS that correct?
I know the MFJ-2990 is copied by the DX Engineering group and sells for $299 - which is $100 less. Could I use the surface of the roof to put out ground planes 2-1/4 waves per each bandwidth? Is that correct?

WA8FOZ
01-01-2009, 07:26 AM
Welcome to amateur radio! I hope that your years ahead will be as rewarding as the last 46 years as a ham have been for me.

Any of these antennas will work well for you as long as it is properly installed. Ground/radials are EXTREMELY important!

Finally, we do not capitalize "ham." How we got to be called "ham radio" is controversial, and has been so for nearly 100 years. But, whatever the reason, it is a word and not an acronym; hence "ham," not HAM.

Have fun!

73,
Bill WA8FOZ

XU7XXX
01-01-2009, 07:43 AM
The thing with verticals is, they radiate equally poorly in all directions! You'll want lots of radials, as many radials as you can put down, and as long as you can make them :).

73 de Joseph Durnal NE3R



1. I made over 45,000 QSO's last year using nothing more than a vertical.

2. When laying down radials for a ground mounted vertical, the ground will "detune" them allowing somewhat shorter radial lengths to be used. Yes, as many radials as you can put down, but as shown in the ARRL antenna book & ON4UN's book, the radials do not have to be near 1/4 wave long.



Tom XU7XXX

W8ZNX
01-01-2009, 11:50 AM
best vertical antenna
there is no best
all antennas are a trade off

pick up a few antenna books
look for used copys of the old 50's 60's
ARRL Antenna Book
find a old ARRL 50's 60's Amateur's Radio Handbook

look for any Bill Orr Radio Handbook
or his antenna books

best off the shelf store bought HF vertical
Hy Gain HT-18 Hy Tower
full size big big antenna
trade off
expensive, but you only pay once
they last
lots of 40 plus year Hy Towers are still in use

next step down
check the Hy Gain Hy Tower Jr.
39 ft tall full 1/4 wave on 10,15,20,40,
cage loaded on 80
no traps, coils, or caps
no strange loading or feed system

the DX Eng 43 ft mono pole
is a better made antenna than the MFJ version
the last 8 ft of the MFJ mono pole is whip, not tubing
but if your going to use a untuned
mono pole expect swr on your coax
and you will need a good outboard tuner

over the last 40 something years
ive helped put up more than one Newtronics Hustler 4BTV
owned a few
its a dog
yea sure your going to work dx with one

you can work dx with anything

a wire inverted L with a few radials underneath it
will leave a 4,5,6, BTV in the dust

one other thing to think about
do you realy want to work all hf bands
160 - 6
sure some ops do use all the hf bands
but many settle for two or three hf bands

example
spend most of my time on 80 and 40 meters

i can count on one hand how many times
ive used 30,20,17,15,10 or 6 in the last 4 years

have a realy good antenna system for 80 and 40

35 years ago ran mostly 15 and 10 meters
had 2 el quad at 45 ft
worked lots of dx qrp

never used 80 meters

lots of new ops think they need a antenna
that works well on all hf bands

in 40 plus years of beeing a ham
ive never had a antenna that did well
on ALL hf bands

my present antenna works great on 80
gets out like gang busters on 40
is ok on 15
is so so on 30

is poor on 20,17,10

many hf antennas
that work on all hf bands and 6 meters
are a big trade off

they are kinda like that
" as shown on TV " do all tool does everything
but
does nothing well

yours truly
mac

oh ps
one simple rule of thumb
when dealing with low band hf antennas

same place, same ground system

larger is always better on 40 and 80 meters
a 39 ft tall vertical

is always going to out perform
a 22 ft tall vertical

dit dit

KI6USW
01-01-2009, 12:16 PM
SO what you are saying is that no antenna can do all freq's well? I can understand that; I mean - that makes sense.
One would need to have two antennas, an antenna 2-way switch, and an antenna tuner. Or maybe three? I don't have the space for a dipole; so that is out of the question at this point. Even if it is a folded dipole, the property doesn't suit the propagation well. So I feel that the Vertical is the only solution.

How would you break up the bands?
Forget 160 - and have one antenna dedicated for 80 and 40? Another for 30 thru 10? Or should I concentrate on 10-30 because I can talk on 10 and listen to 12, 15, 17, 20, and 30?

I need a plan to work with before I buy another stitch of gear. The more I research the IC-718 it comes up a keeper, and the LDG Z-100 has a lot of great revues too. So I guess I have done right by those who commented here so far.

GeorgeRaft
01-01-2009, 01:17 PM
I never understand it.

It always seems now that about the first thing a noob thinks they must just have is a so-called auto-"tuner". A must have before ever operating or even putting up any sort of antenna...or even powering up the new little rig.

Then instead of just making a short dipole and putting it up, they never have the "room" or space for it. Not even for 10 meters...nor just some wire to listen where they have no prilvieges to transmit.

Then they must just have to have a expensive "all band" vertical, which should not even require any kind a "tuner" at all.

The world just gets stranger and stranger.

Happy 2009 to all.

KG4JJS
01-01-2009, 01:44 PM
Hey Folks:

Went down to Ham Radio Outlet today and bought my first HAM rig.
It's an Icom IC 718. I also bought a LDG Z-100 that also plugs right in the back of the radio for power and an internal feed/switch.
Sweet!

They also had a $50 rebate. So the price was $559+tax-$50 mail-in rebate for the total out-of-pocket price for a new Icom and a new HAM.
Did you think I did all right?

I don't want to get a dipole. Because, although I have a house I don't have the space to stretch it out or do a "V' out of it either. So, I need to get a really decent Vertical antenna. Also, I want to reach as much band as I can, even if it is just for listening at this point. I hold a Tech license, and I plan to get my General license this year. So I need a radio that work for me as I listen. So what is the best for the $300 range?
Thanks for all replies ahead of time!

I use the Ma5v Cushcraft vert antenna.Its good for 20 meters thru 10 meters including warc bands.Its small and requires no radials.Downside is it can only handle around 100 watts or so.I also have the ldg z100 tuner and ic 718 icom and have talked around the world on this vertical.
73
Tim

W8ATA
01-01-2009, 01:47 PM
Wecome to ham radio! First, I think you made a good decision in buying the IC-718. It's one of the best, if not the best, basic entry level rig on the market today. But that's just my opinion. It's a rig you may want to keep for a long time even if you move on up to a rig with more features. And you can start listening today by hanging a wire out somewhere.

On the vertical question, you may get as many opinions as there are verticals out there. Some will be from hams with experience with a particular vertical and others will say "I heard the model XYZ is a great vertical". My advice would be to spend $17 plus postage and order the white paper "HF Vertical Performance, Test Methods & Results" by Ward Silver, N0AX and Steve Morris, K7LXC and published by Champion Radio Products. You can find Champion with a Google search. Before Ward and Steve began their testing they had their protocols reviewed by K2AV, W8JI, and the late W4RNL. All verticals were tested under the same protocols and test conditions. It is truly an enlightening read and may have a few surprises for you, not the least of which is that you don't have to spend the big bucks for an HF vertical.

The $17 was money well spent for me. And yes the "consumer report" on verticals is copyrighted. I paid my $17 and I don't make copies for others. And I have no affiliation with the authors or Champion. I just like their product.

73,
Russ

N5CE
01-01-2009, 01:59 PM
Let me add my welcome to the others.

I have a 718 and I love it. I think you'll enjoy the radio. Mine has the high stability oscilator option and an Inrad 400 Hz filter for CW. Both are pricy add ons but well worth it. I think I would do the filter first if you are interested in CW. If not now, hopefully in the future. It can be a lot of fun.

On the antenna front, look at the Hy-Gain AV-640. It is a radial-less design. I've worked all over the world with mine mounted about 10 feet above the ground with a sort mast bolted to the chain link fence post. The bottom needs to be that far off the ground so you can walk under the drooping lower elements.

It won't cover all of 40 meters so you have to decide which end of the band to set it up for. Another silightly less expensive and smaller version is the AV-620 but it does not cover 30 meters which is a great band. Once you have it set up and fine tuned you won't need a tuner.

Get something up quick and get on the air with it.

Let us know what you decide and how it works.

Best 73's
Marty
N5CE

KD8CMN
01-01-2009, 02:49 PM
Welcome to the wonderful world of ham radio! I have had great success with the Gap Titan DX. Just my 2 cents.

N8FGB
01-01-2009, 04:33 PM
If you have an A99 for your cb radio. You can get decent results on 10,12,15,17 meters.And fair on 20. That will allow you a start, and give a chance to learn and look at antenna options.I bought one for 2 bucks at a yard sale, works great. A new general down the street just hung what wire he could get up, and it works great.
Rich

K3WRV
01-01-2009, 04:48 PM
Welcome-

Over the years, I've used several verticals, ranging from a "Gotham style" to a Hygain 12AVQ (20-10, no warc) and a Hustler 5BTV. The Gotham is simply a 15 foot long section of aluminium tubing with a miniductor base loading coil. The Hustler was $30 used and the Hygain was $5, both from hamfests. The Gotham was less than $20 - you can find plans in the antenna books. They all gave pretty similar results, but none of them consistently performs as well as a dipole, Mac is probably correct about the Hytower.

I use my verticals primarily as backups, because there are better antennas, IMHO.

K9STH
01-01-2009, 04:55 PM
The "problem" with a vertical antenna is that when properly installed they have a low angle of radiation which is great for working DX. Unfortunately, a low angle of radiation is not good for working closer in stations. That is why verticals have a reputation of being an antenna that radiates equally as poor in all directions.

I have a HyGain HyTower that has been up for over 35 years as well as a 40 meter vertical that I phase with the HyTower for 40 meter operation. These are in addition to other antennas (go to http://k9sth.com/uploads/newantenna.JPG for photos). For contacts out to around 700 miles the verticals are pretty worthless and wire antennas at a relatively low height perform much better on the bands below 10 MHz. But, for contacts over 1000 miles away a single vertical does very well and for working DX on 40 meters the phased verticals are very difficult to beat even with a full sized 3-element yagi. For those contacts between 700 miles and 1000 miles sometimes one of my wire antennas works better and sometimes it is one of the verticals that works better. It all has to do with the angle of radiation of the signal.

I use elevated radials on my verticals they work considerably better than buried radials. Since I use the HyTower primarily for 80/75 meters and 40 meters I have 4 radials cut for 80 meters, 4 radials cut for 40 meters, and 4 radials of random length. Those run along my stockade fence, along the retaining wall to my swimming pool, and along the side of my house. Before my swimming pool was installed I had 48 buried radials under the HyTower and, to put it bluntly, the elevated radials work considerably better than the buried radials ever did. The ground conductivity at my location is considered by the U.S. Government to be among the best in the contiguous 48 states. At one time there were no less than 3 commercial antenna ranges within 3 miles of my house (Collins Radio, Texas Instruments, and Electrospace) for that very reason.

If you are only interested in working stateside stations then a fairly low wire antenna is going to work better than a vertical in most applications. If you are interested in working DX then for a simple antenna a vertical is going to work very well. However, if you are interested in working both stateside and DX then you really need to consider having more than one type of antenna.

Glen, K9STH

N9ZMO
01-01-2009, 06:59 PM
Welcome to the wonderful world of ham radio! I have had great success with the Gap Titan DX. Just my 2 cents.


I also have had very good luck with the Gap Titan DX. This spring the plan is to put up a tower and add Yagi's to the mix.

Kurt

W4PG
01-01-2009, 11:01 PM
So, it's between the Hustler and the Cushcraft.
Which one has better gain?

Ignore any published "gain" figures for verticals. They don't have any, radiating equally poorly in all directions. But, you can work the world with them when conditions are good.

I've used the Cushcraft R-series (R-5, R-7 and R-8) verticals for years, chimney mounted. The R-8 is a little big (it works on 40 meters) and one really should use the guying set with it to keep it from turning into a banana. These antennas are designed without the need for full-sized radials, which are typically necessary for standard verticals. Hi-Gain also makes a similarly designed antenna that works well too. If you check out a picture of one, you'll see how they have designed the "radials" into the antenna near the feed point.

Bear in mind that most man-made noise is vertically polarized and you will tend to pick up more noise with a vertical than with a horizontal antenna. If your rig has a decent noise blanker, it will help.

.........Bob

W2PHD
01-01-2009, 11:28 PM
Hey Folks:

Went down to Ham Radio Outlet today and bought my first HAM rig.
It's an Icom IC 718. I also bought a LDG Z-100 that also plugs right in the back of the radio for power and an internal feed/switch.
Sweet!

They also had a $50 rebate. So the price was $559+tax-$50 mail-in rebate for the total out-of-pocket price for a new Icom and a new HAM.
Did you think I did all right?

I don't want to get a dipole. Because, although I have a house I don't have the space to stretch it out or do a "V' out of it either. So, I need to get a really decent Vertical antenna. Also, I want to reach as much band as I can, even if it is just for listening at this point. I hold a Tech license, and I plan to get my General license this year. So I need a radio that work for me as I listen. So what is the best for the $300 range?
Thanks for all replies ahead of time!

I am very pleased with this great vertical antenna. I highly recommend it.

http://www.wb0w.com/hygain/Antennas/av640.htm

W2PHD
01-02-2009, 12:05 AM
Welcome to amateur radio! I hope that your years ahead will be as rewarding as the last 46 years as a ham have been for me.

Any of these antennas will work well for you as long as it is properly installed. Ground/radials are EXTREMELY important!

Finally, we do not capitalize "ham." How we got to be called "ham radio" is controversial, and has been so for nearly 100 years. But, whatever the reason, it is a word and not an acronym; hence "ham," not HAM.

Have fun!

73,
Bill WA8FOZ

The "we," a special group of hams dedicated to kibitzing other newbees like yourself.............A killjoy no doubt. An elite member of the "Chosen Few."

Have fun yah say..........after that salvo how the opposite of heaven can he with scrutiny abound. This new ham deserves an apology, if you are a gent.:cool:

Please just enjoy the hobby and don't worry about comments like that one. If HAM isn't an acronym, then I suppose we are to assume that EXTREMELY is???:rolleyes:

HAM Hak Asasi Manusia (Indonesian: Human Rights)
HAM Host Adapter Module
HAM Hold And Modify (Amiga Graphics Mode)
HAM Handheld Amateur Radio
HAM Honda of America Manufacturing, Inc. (automobile manufacturer)
HAM Hamburg, Germany - Fuhlsbuttel (Airport Code)
HAM High Altitude Mountaineering
HAM Humans Against Monsters (gaming, Runescape group)
HAM Hydrogenic Atoms in Molecules
HAM Health, Action, Mind (Star Wars Galaxies)
HAM Humans and Monsters (internet comic)
HAM Hospital Account Manager
HAM History, Allergies, Medications (medical)
HAM Hankel Approximation Method
HAM Haul Ass and Move
HAM Hose Assembly Machine
HAM [not an acronym] slang for Amateur Radio Operator
HAM Heat Alcohol Massage (things to avoid post Iinjury)
HAM Hierarchical Archive Manager

How rude, a new ham asks for advice and what does he get?............Corrected before he gets out of the gate.

What a bunch of anal cavities these Holy Joe six packs (that's Palin for you) are 4X's sake.:cool:

Remember it's the doughnut and not the hole, booby!

K9STH
01-02-2009, 12:06 AM
DFW:

Depending on the vertical antenna design it is definitely possible to have actual gain over a quarter-wave. In fact, a normal quarter-wave vertical has a 2.14 dBi gain (gain over isotropic). A 1/2 wave, 5/8th wave, and 3/4ths wave vertical all have approximately a 3 dB gain over a quarter-wave with radiation patterns differing with the exact length.

Then there is the practice of phasing verticals which achieves additional gain.

The original HyGain Hytower has measured gain around 2 dB over a quarter-wave vertical on certain bands.

As I pointed out before, a PROPERLY installed vertical is NOT an antenna that radiates equally as poor in all directions. Yes, due to the angle of radiation a properly installed vertical definitely has a lower angle of radiation than most simple antennas (including dipoles) and therefore is NOT generally good for closer in contacts. That is why the vertical gained a reputation for being a poor antenna while a vertical is generally very good for working DX.

For man made noise a vertical is generally around 20 dB more sensitive than a horizontally polarized antenna. For atmospheric noise there is generally no difference between a vertically polarized and a horizontally polarized antenna. For those stations located outside of urban or suburban areas a vertical antenna is usually as quiet as a horizontal antenna. Unfortunately, for the majority of us who live in urban or suburban areas we do have to "put up with" man made noise.

Just like various horizontal antenna designs there are a lot of commercially produced shortened vertical antennas that are not among the best performing antennas. Then there is the practice of using "traps" and/or loading coils for multi-band operation. Depending on the absolute design of the antenna the degradation of the performance can range anywhere from minimal to dismal. Then there is the installation of the vertical itself. Frankly, a vertical generally requires an excellent counterpoise and many amateur radio operators do not know how to, do not have the resources, or just plain do not care about installing a proper counterpoise system.

Like has been pointed out previously, there is no antenna know known that is not a compromise in performance. As such, you really have to make a decision as to what type of operation you wish to undertake the majority of time and decide on which antenna is going to be best to accomplish this. When working outside of these parameters you just have to "take your lumps" when making contacts.

Glen, K9STH

KI6USW
01-02-2009, 01:35 AM
I just read on eham.com a guy completely destroy my fragile image of the IC-718. Since I haven't taken it out of the box yet - nor sent in the $50 rebate form - I still have ten days to return it and use the credit twards another unit. I want an Icom; but the Yaesu FT-450 is about $170 more. And it does 6 meters and is supposed to be far superior to the IC-718. But, I am new at this - and too many controls on a radio is a bit intimidating at this point. My 'fragile image of the IC-718' is based upon the thought of spending money foolishly, as I had hopes to do my first station under $1,000.

Don't get me wrong; I used to have my own recording studio with an TASCAM 8 track tape machine and all of the many accoutrement's that made it quite formidable. As well being able to use all of it - which nearly takes a degree to do - too. But my background to Amateur radio is based in CB; and they are not as nearly complicated as Ham rigs as you all know. I still have an Archer 1/2 wave antenna hooked up to my CPI/CP 2000 radio/D104 T-UP9. The noise issue of the IC-718 and a Vertical antenna seems like it is destined to be a hash monster. I am concerned - to say the least. I want to know that I made initially good decisions as regards to gear, but changing midstream to the FT-450 and its comparatively high user experience level makes me want to stick to the hash monster IC-718.

As far as the vertical is concerned, for the money it appears that the GAP Challenger is winning. Having more than one antenna will be the means for change and expansion of the small Ham shack. But I need a starter antenna - even if it has limited use in the 10-80 meter range; I must decide within the next few weeks. Ther is a flea market at the local college and it can be a source for a cheap antenna - so long as I know what to look for. Or, I am fully prepared to buy one new, so long as I am fairly certain that it was money wisely spent. The next HamFest near here won't be for another month. I have all of that time to figure out my next move.

Please, I would appreciate any directions and useful subject matter to continue and thrive. I am reading every post - twice - and extracting everything.
Thanks!

K8JCM
01-02-2009, 01:51 AM
I live in an apartment building and have an inverted vee setup on the roof. Just mounted a cheapie antenna pole at the peak, mounted the centerpoint of the 40M dipole on it, and ran the leggs down to the roofline front and back. It works great!! I use a 706 with a MFJ 929 ant it'll tune all but 160 meters.. My suggestion is to experiment and you'll find what works best for you.

73 K8JCM
Jerry:)

K4LSX
01-02-2009, 02:31 AM
ignore the drivel about "equally poor in all directions"...it is true, but a fact of life...a 1/2 wave dipole at "ideal" height above earth also radiates incredibly poor at the zenith. "all directions" is a fact of life with a vertical (omnidirectional - duh!) radiator.

I have used many verticals as well as dipoles and yagis...have just as much fun with verticals as anything...best vertical I ever had was the 18HT...now using the 43' Zero-Five. Always had really good radial systems, always had really good results.

Most of the fun is making one work real good then taking it apart and trying something different.

whatever you put up, have fun with it, and learn something while doing it!

:D

73,
John

KD8HTU
01-02-2009, 03:31 AM
Greetings Robert,
Check your pm
73 Marty

W4PG
01-02-2009, 06:05 AM
DFW:

Depending on the vertical antenna design it is definitely possible to have actual gain over a quarter-wave. In fact, a normal quarter-wave vertical has a 2.14 dBi gain (gain over isotropic). A 1/2 wave, 5/8th wave, and 3/4ths wave vertical all have approximately a 3 dB gain over a quarter-wave with radiation patterns differing with the exact length.

Glenn, you absolutely correct. I had even written in the gain over a dBi source as you pointed out, but edited it out since I think it can be confusing. Additionally, the typical vertical that it sounded like the original query was about didn't seem like a 1/2 wave or larger vertical was a practical reality. I didn't think phasing verticals was an option for the gentleman, either, hence I didn't mention that.

I used an HT-18 for a few years when I was first licensed. It's arguably the finest vertical antenna available for hams, and when putting two or more of them in phase, can make an absolutely outstanding DX antenna for 40 and 80 meters. One needs a bit of real-estate to make that happen, however. I'm stuck with my 40 meter beam and 80 meter dipole and just not the right lot for those phased HT-18s, though I dreamed about that as a kid!!

............Bob

KC7YPJ
01-02-2009, 06:58 AM
your going to get allot of "buy this" advice, so here's mine, go buy a spool of galvanized electric fence wire, a waterproof box big enough for your ldg, 1 piece each of 1", 3/4", 1/2" emt conduit or other similar conductive tubing that will slide inside each other, a few 1/4"x1-1/2" bolts with nuts, and whatever guying material your grey matter can think up.
lay out as many radials as you can with the elctric fence wire around your telescoping pole (pvc pipe with an end cap makes a nice insulator), run coax to your ldg inside the waterproof box, and short jumpers to the vertical (center) and radials (ground), enjoy. the performance will suprise you, even on bands it shouldn't work well on, and it won't cost you much to build.

nearly all vertical designs require a good groundplane to work corectly , some may work and "load up" without them, but so does a dummy load.

now if you happen to be blessed with a tall tree to hang a wire from you can replace the tubing with a single 14g stranded wire hanging from a rope thrown over a limb, make it as long (aka tall) as you can and try it, odds are it's going to work as good or better than a several hundred dollar "production" vertical over the same radial field.

I have been told over and over again that my vert is garbage and can't possibly work (largely due to how it's fed) but new zealand and japan don't seem to have a problem hearing it vs an inverted v or large flattop doublet so I screwed up in a good way, mines 57'-6" overall, 49' of it is creatively sleaved 1",3/4",1/2" emt conduit with an old 102" stainless whip antenna on top, over a field of 36each 50', 25' and 12.5' radials.
ok so I went overboard, 160-30 are all that really interest me anyway.

point is, read up on the subject, and realize that you don't have to have brand x antenna to have it work, and often times the one you build yourself will outperform anything the market has to offer.

K9STH
01-02-2009, 04:37 PM
For 90 degree phasing on 40 meters all that is required is a 35 foot spacing between the verticals. That can give up to a 4.5 dB gain with a cardioid pattern in the direction of the phasing and about a 20 dB null off the back. At 90 degrees to the maximum gain you still have around 3 dB gain. By making the phasing so that the pattern can be "flipped" you can get gain over 360 degrees.

That is what I have on my phased verticals. My suburban lot is 72 feet by 130 feet with rear entry. Therefore, my backyard is about 40 feet square and there is a swimming pool that takes up a good portion of that. However, I can get the 35 feet spacing of the verticals on a line that peaks either to Japan or South America. No matter how I "flip" the phase I still have about 3 dB into Europe and Australia. Due to the fact that I am almost at the top of a hill (highest point in the city is 1/2 block away) it is "downhill" for over 300 degrees and then for the other 60 degrees it is downhill after 1/2 block, the apparent gain is better than the expected 4.5 dB. Also, having elevated radials and soil conductivity that is rated tops in the 48 contiguous states doesn't hurt!

Glen, K9STH

AI3V
01-02-2009, 05:13 PM
Before you spend money on a vertical antenna, Buy this book:

https://www.alibris.com/search/books/isbn/0823087107

(All about verticals, Orr and Cowan)

As otheres have said, you can build better than you can buy.

Rege

WD0GOF
01-02-2009, 05:15 PM
Look at the Gap Titan DX. It is a center fed vert. and requires no radials. The antenna is on an 18 ft mast tied to the end of the house. Each of the General phone bands came in at less than 1.7:1 at the ends and less than 1.2:1 in the center. With the SR-2000 at full power I had a little RF in the shack. I wound a coax current choke on 4 1/2 inch OD pvc and installed it at the base of the antenna and that cured that with no degradation of the system. I am pleased with it's performance. Photos @ http://www.myhamshack.com/WD0GOF/

KL7AJ
01-02-2009, 05:16 PM
The thing with verticals is, they radiate equally poorly in all directions!
73 de Joseph Durnal NE3R

You mean like broadcast towers? :confused:

K0RGR
01-02-2009, 05:52 PM
I've read too many negative things about GAP antennas, though many people swear by them, too.

I had an 18HT HyTower for many years, and I've never found anything short of rotary beams very high in the air that would compete with it on 40 and 80 meters for working DX. But, as Glenn described it, for other than working DX, verticals are a bit challenged. I did a lot of QRP work on 40 meters with the HyTower, and I really had fun with 5 watts in the DX contests!

I will also give you a ringing endorsement for the Hustler 4BTV. I don't think there is really much advantage to the 5BTV or 6BTV over the very cheap, entry level 4BTV. The 80 meter coverage provided by the 5BTV can be useful, but it's not a world-beater. I've put more than one 4BTV on a chimney mount, and with at least 3 radials for each band, it will be a good performer for you. Since you live near the west coast, a vertical will let you work the east coast much better than a low-strung dipole will.

I also had good luck with a Cushcraft R-5, until it failed mechanically. It was a poor, but adequate 40 meter antenna, but it did work well on 20 and up. Attempts to repair it were not entirely successful, and for the price, the Hustler is a better deal, even though you have to deal with radials.

Now, having sung the praises of the vertical, it's big shortcoming is noise. Verticals tend to receive noise in housing developments because the noise tends to be vertically oriented. No modification to your radio is going to help it, beyond having a great noise blanker circuit and/or DSP noise filters.
Usually, the noise is worst on the lowest band or bands - it typically drops off around 40 meters. A separate, low-noise receive-only antenna can overcome these ills, and they don't have to be large.

Having a variety of antennas is a good thing. When I lived in Silicon Valley, we started out with the HyTower, and we thought it worked great on all bands, until we put up a decent horizontal wire antenna, which worked much better for working the western USA on 40 and 80 meters. Then, we added a tribander, which worked much better on 20 meters and up. So, some antennas work OK on all bands, but no matter what you have, there is something better!

Likewise with your choice of radios. I've seen the IC718 in action ,and it is a decent little radio. I would expect it to give you good performance for some years to come. But, as a Tech, unless you choose to learn CW, you can only use it to transmit on 10 meter SSB. If I were going to swap radios to get more bands, though, I'd look at the FT-857, or IC-706. Those would also give you SSB on 6, 2, and 432 Mhz., as well as FM functions.

W6ONV
01-02-2009, 08:13 PM
KI6USW. Wow! That was the same setup I purchased last June when I upgraded to General, the IC-718 and the LDG Z-100. I compared a list of 5 or 6 vertical antennas, on various criteria and decided on the Hustler 6-BTV. It was somewhat of a compromise based on different factors, but I have been very happy with how it has worked since I have begun HF work.

Originally I mounted it on a 10' mast, but the HOA got mad and made me take it down. When I worked out the HOA problems I went forward and purchased a tilt-base, radial plate and choke to connect to the vertical and started working on adding radials to my setup. Currently I have 45 radials installed with lengths varying between 7' and 45' in order to fit the shape of my backyard.

It is a very simple vertical to work with and tune, as long as you read the Tech Info from DXE on their web site. Some traps had to be adjusted, but I do find the SWR acceptable on all bands. One thing I was told (on QRZ I think) was to remove the Z-100 from the setup, so I did and have not looked back.

Since getting onto HF I have worked 47 states and 20 countries mainly on PSK31, but have received good signal reports on RTTY and CW. I can't really comment on SSB since I have really only made one non-contest QSO with KH6 who reported '55' all the other SSB contacts were contest '59' reports.

So overall I am pleased with my ham radio situation, while not an optimal situation, at least I can work world. Hopefully when sunspots return I will be able to work more of the world.

MM0JVB
01-02-2009, 08:23 PM
i know you said you didnt want a di-pole but have a look at these.

http://www.moonrakerukltd.com/Amateur-Radio/Di-Pole-Antennas/Mini-HF-Di-Pole

the 20mtr one on a small tv rotator & will work you exellent dx ,the higher the better & unbelievably directional , this company also do 5 band verticals , 10-80 mtr

W4PG
01-02-2009, 09:51 PM
For 90 degree phasing on 40 meters all that is required is a 35 foot spacing between the verticals.

Glenn, you're going to get me in trouble!! I just put up an 89 foot US Tower with a 2 ele 40 meter beam and a 4 ele SteppIR. If I tell the XYL I'm planning on putting up two - 50 feet verticals, she'll KILL me!! :eek::D

I would want to phase them for 80 meters, anyhoo. Uhm . . no, stop, please DON'T get me going . . . . :p

W0DV
01-02-2009, 10:16 PM
I am very pleased with this great vertical antenna. I highly recommend it.

http://www.wb0w.com/hygain/Antennas/av640.htm

Isn't your antenna 90' above the ground on top of a building? At that height you can tune up almost anything and yield good results in relation to what many hams have available to them!

K9STH
01-02-2009, 10:43 PM
DFW:

For 90 degree phasing on 80 meters you will need like 70 feet between the verticals! :rolleyes:

Glen, K9STH

KI6USW
01-03-2009, 12:50 AM
i know you said you didnt want a di-pole but have a look at these.

http://www.moonrakerukltd.com/Amateur-Radio/Di-Pole-Antennas/Mini-HF-Di-Pole

the 20mtr one on a small tv rotator & will work you exellent dx ,the higher the better & unbelievably directional , this company also do 5 band verticals , 10-80 mtr

I like dipoles; but the shape of my property and its dimensions won't permit it. Ideally, I would like to have a 160-2 meter folded dipole. But my property only has 55 ft of space north to south; and 100 ft of space east to west. So, my propagation direction wouldn't work out for east to west propagation if I used the longest side of the property. That is the main reason for the vertical. Power usage has nothing to do with antenna choice; as my LDG Z-100 is only good for 125w and I can only talk on 28.3 -28.5 Mhz SSB any way - since I am still a Tech.

I would like to have and use a dipole because of the useable local/distance factor - and that it is got great SWR specs. Is there any folded diploles that use 40-2 meters that I can build or buy? Remember - that only have 55 ft to work with north to south - and even that is awkward. So I hope you can see why a vertical is my last but only real choice. The dipole in the link would need to be stacked with other similar dipoles with different bandwidths, rotated, and switched - and end up with a large cost.
Thanks!
73's!

NA0AA
01-03-2009, 02:30 AM
Well, there's a million opinions as you can see.

I bought an SGC antenna coupler from a friend, and decided that it would serve well for a vertical.

I used the 33' tall lightweight fiberglass pole from MFJ minus the very tip section, and ran a 12 gauge wire hanging inside it full length. This pole is clamped to a wooden fence post with the coupler mounted below it - a ground rod was installed and radials added.

It's a LOUSY performer for 80 or 160. It may be a lack of long radials, or the fact that the radiator is just way short for efficient operation. My fan dipole for 40/80 is a better performer at 35' above ground.

On 40 it's decent, and on 20 up it's a pretty good performer for me - better than 1/4 wave verticals for 10 and 20 that I can compare with.

If you can get any antenna on the roof it will perform better than a ground mounted vertical, generally speaking.

VK3FTIM
01-03-2009, 06:16 AM
Hey Folks:

Went down to Ham Radio Outlet today and bought my first HAM rig.
It's an Icom IC 718. I also bought a LDG Z-100 that also plugs right in the back of the radio for power and an internal feed/switch.
Sweet!

They also had a $50 rebate. So the price was $559+tax-$50 mail-in rebate for the total out-of-pocket price for a new Icom and a new HAM.
Did you think I did all right?

I don't want to get a dipole. Because, although I have a house I don't have the space to stretch it out or do a "V' out of it either. So, I need to get a really decent Vertical antenna. Also, I want to reach as much band as I can, even if it is just for listening at this point. I hold a Tech license, and I plan to get my General license this year. So I need a radio that work for me as I listen. So what is the best for the $300 range?
Thanks for all replies ahead of time!

Congrats on the new tuner and Radio

I have the same tuner and radio lol

For my Vertical i have a Diamond CP6 HF multiband vertical which covers 80 Meters 40, 20, 15, 10, 6

Note this antenna has ground plane radials which are are the longest 1.7 meters long

With the tuner this antenna will take you across the whole amatuer band :)

Enjoy and hope to catch you on the band soon

W2PHD
01-03-2009, 01:15 PM
Isn't your antenna 90' above the ground on top of a building? At that height you can tune up almost anything and yield good results in relation to what many hams have available to them!

That was the plan OM. :) It's nice to see that people read the details from time to time.:D

Cheers:)

N8CPA
01-03-2009, 03:01 PM
You might check out the Diamond BB7V.

It is a 23ft, 2~30MHz, no trap, no radial vertical designed for use with a transmatch. It works okay, considering that it's a compromise all-in-a-single-package antenna, which means that it loads nicely. But so does a dummy load. Nevertheless, I have managed to work all states and all continents on it with cooperating propagation and CW.

I don't believe the claim that it needs no counterpoise. Every vertical I've ever seen works better with one. I don't see why this design would be an exception--unless the feedpoint enclosure actually contains a tightly coiled version of one. I have it mounted about 40 feet above ground, but have not tried lower to the ground, which may or may not improve performance.

When we move, I may ground mount it, but replace the current feed point system with a remote coupler, and as many radials as I can bury.

One interesting thing about it is the instruction manual. It reads like a minimum wage translator worked late at night after many ochoko of sake.

http://www.diamondantenna.net/bb7v.html

K0RGR
01-03-2009, 04:31 PM
Do be aware that dipoles don't have to be straight to work. I had a very small suburban lot at my last house, and managed to incorporate several antennas that shouldn't fit there.

I had an 80 meter dipole that, looking down from the top, was shaped like a 'Z'. The center support was about 30 feet high, and the legs went down to poles about 15 feet high. It was not a Big Gun DX antenna, but it worked well for domestic contacts.

I really think the best wire antenna I ever had up there was a 'Maltese Loop' for 40 meters. This was a full-wave loop for 40. If you do the math, the formula for the loop is 1005/F in Mhz. - too big for most back yards. But by making it a 'Maltese' design, by pulling the corners in to the center like the shape of a Maltese Cross, I was able to reduce the overall size by about 1/3. I think it actually performed better than the full-sized loop that replaced it. I fed it directly with coax, and it had a decent SWR on 40, 20, 15, 10 and 6 meters. I wound 18 turns of RG-8X around a 2 Liter Pepsi bottle as a choke balun. Unfortunately, the XYL declared it too ugly to survive, so it didn't.

I don't think a 'folded dipole' is what you think it is. A 'folded dipole' is just a dipole built to match to a higher impedance feed than a regular dipole. It's not a bent dipole, like the 'Z' design described earlier.

You can build multiband dipoles but that requires that you either cut separate dipole elements for each band, and feed them in parallel - known as a 'fan dipole', or, you build or buy 'traps' to insert in the legs of the 80 meter dipole to effectively cut off pieces of the antenna as you go up the bands.

As I mentioned, full-wave loops work on all of their harmonics, so one cut for 40 meters will work on 20,15, and 10 too. Now, you can also use loops as non-resonant antennas on any band slightly lower, or higher than the design frequency. A loop cut for 5 Mhz. should work on 80, and all the higher bands, too. But, a tuner is required. QST published a design some years ago for a 'stealth' antenna that consisted of a 5 Mhz. loop suspended in a tree. The top center of the loop was at the top of the tree, and legs of the loop wound around the tree, like two strands of Christmas lights. At the bottom, they installed a remote auto antenna tuner. Obviously, this design needs a fairly big tree in the yard, and autotuners aren't real cheap. You can also feed the loop with open wire feeders back to your shack.

Here's an 8-band wire antenna with no traps. I had one like this up years ago, and it was a great performer, but it was pretty high, too. http://www.kh2d.net/windom.cfm I would not worry at all about bending it to fit my lot.

W2PHD
01-04-2009, 03:56 PM
You mean like broadcast towers? :confused:

Great answer.:)

KI6USW
01-05-2009, 04:55 AM
I'm studying for my General, and coming along fine right now. I plan on taking the exam within the next two weeks or so.
I have decided to get a Hustler 5BTV for a vertical, a coax switch, and a dipole that is 67 ft (more or less) in overall length.
Here: http://www.radiowavz.com/html/dx_ocf_windom.htm
So let's say that I get a dipole. 10-40 meter because of dimensional considerations and limitations.
Which would be best?

G5RV, end feed, or Windom?
Which has the best broadband characteristics 10 thru 40 meters? This is an issue that I am very keen on.
Is any brand better than another; more consideration to materials and finer engineering?
How high off of the ground is best for the 10-40m range? A 1/2 wave from which freq? What would be the advantage of a 4:1 balun and why would it need to be used? Besides impedance matching; what does it offer? How do you go about grounding a dipole system - or isn't it necessary?
Remember, you are not just answering an engineering question, you are helping me study for my exam by your instruction...

AI3V
01-05-2009, 03:11 PM
I'm studying for my General, and coming along fine right now. I plan on taking the exam within the next two weeks or so.
I have decided to get a Hustler 5BTV for a vertical, a coax switch, and a dipole that is 67 ft (more or less) in overall length.
Here: http://www.radiowavz.com/html/dx_ocf_windom.htm
So let's say that I get a dipole. 10-40 meter because of dimensional considerations and limitations.
Which would be best?

G5RV, end feed, or Windom?
Which has the best broadband characteristics 10 thru 40 meters? This is an issue that I am very keen on.
Is any brand better than another; more consideration to materials and finer engineering?
How high off of the ground is best for the 10-40m range? A 1/2 wave from which freq? What would be the advantage of a 4:1 balun and why would it need to be used? Besides impedance matching; what does it offer? How do you go about grounding a dipole system - or isn't it necessary?
Remember, you are not just answering an engineering question, you are helping me study for my exam by your instruction...

What books on antennas have you read?

Rege

KI6USW
01-09-2009, 05:12 AM
So I bought a Windom OCF 10-40 meter from Ham Radio Outlet for $60. Should get here after I get my General License this weekend. Got to go and study now...

W3SIX
02-07-2009, 11:12 PM
I've used verticals, dipoles, half-squares.... all have their place. A few years ago, when the only HF I was licensed for was 10 meters, I got WAS and DXCC using a no-radial CushCraft AR-10 vertical. It was about 18' feet tall and mounted on a 20' pole. The counterpoise was a ring about a foot in diameter.

Did I break any pile-ups? Not really, but patience and learning when to listen and when to transmit did the job.

Ed

EI8DRB
02-08-2009, 12:25 AM
As for your situation and supposed issues with your dipole orientation... you should be aware that for a dipole to exhibit any sort of directionality, it needs to be .5 wavelength above ground. That's 66' on 40m. Any lower and the majority of your signal is going straight up, or certainly at a steep angle. Not that this is a bad thing... you'll work loads of states on 80m with a lowish antenna.

I have to say, that if it was me, I wouldn't waste my time waiting for the 'perfect' vertical... I'd just get some wire up in the air and start working stations.

N0JEF
03-24-2010, 01:57 AM
Hey Folks:

Went down to Ham Radio Outlet today and bought my first HAM rig.
It's an Icom IC 718. I also bought a LDG Z-100 that also plugs right in the back of the radio for power and an internal feed/switch.
Sweet!

They also had a $50 rebate. So the price was $559+tax-$50 mail-in rebate for the total out-of-pocket price for a new Icom and a new HAM.
Did you think I did all right?

I don't want to get a dipole. Because, although I have a house I don't have the space to stretch it out or do a "V' out of it either. So, I need to get a really decent Vertical antenna. Also, I want to reach as much band as I can, even if it is just for listening at this point. I hold a Tech license, and I plan to get my General license this year. So I need a radio that work for me as I listen. So what is the best for the $300 range?
Thanks for all replies ahead of time!

Just use your IMAX 2000 Robb

AD6KA
03-24-2010, 03:00 AM
"I have to say, that if it was me, I wouldn't waste my time waiting for the 'perfect' vertical... I'd just get some wire up in the air and start working stations."

That's the best response I've read in this entire thread.

Often new hams will fall into the trap of getting obsessed over
buying exactly the right rig, the "best" antenna, an antenna
that will "cover all the bands" etc, etc.

By all means buy a good antenna book and do your research.
Yes, the antenna IS the most important part of your station.

But nevertheless, work on your operating skills at the
same time, even with a "good enough for now" antenna.

A good operator with modest equipment will always run circles
around (make a lot more contacts than) a crummy operator with
good equipment.

W0SGM
03-24-2010, 11:30 PM
S9V vertical works as well as any vertical and they are cheap.Use a 4:1 unun and a wide range tuner ( I use an LDG Z11Pro,tunes everywhere 60-6m,it'll even tune on 80m,but probably doesn't work worth a darn there) or a remote tuner,and add some radials .

K7UNP
03-25-2010, 03:04 AM
S9V vertical works as well as any vertical and they are cheap.Use a 4:1 unun and a wide range tuner ( I use an LDG Z11Pro,tunes everywhere 60-6m,it'll even tune on 80m,but probably doesn't work worth a darn there) or a remote tuner,and add some radials .

I'm with you....I use the same setup and cannot even believe how well it does.
I've got 900 feet of wire on the ground and it rocks!

Bob O.

N8CPA
03-25-2010, 12:30 PM
USW, let us know when you finally conclude: "One antenna ain't enough!" My next installation will include at least one RX only horizontal.

K5BDH
03-25-2010, 12:50 PM
I'm like the previous posters, It's hard to beat the S9v, jus got mine and put a Z-11 pro at the base and it works like a champ. Only issue is getting rfi on 20 and 15m for some reason or another. I use the 80m coil on mine and can tune from 80-10 less than 1:5:1.

Goodluck

W8JI
03-25-2010, 03:12 PM
I'm like the previous posters, It's hard to beat the S9v, jus got mine and put a Z-11 pro at the base and it works like a champ. Only issue is getting rfi on 20 and 15m for some reason or another. I use the 80m coil on mine and can tune from 80-10 less than 1:5:1.

Goodluck


None of these verticals are magic, and the fact they do not have traps and have less loss is really a big marketing fib. For the last 15 or 20 years marketing people have been feeding amateurs a toxic kool-aid about traps.

The loss of an UNUN at the base, a length of coax, and a tuner at the antenna base (or in the house) will easily dwarf the loss of typical antenna traps.

Even one trap vertical, the Butternut, now claims its traps are not traps, just as another company claims its traps are not "lossy traps" but "resonators", because marketing people have just totally destroyed the reputation of traps for no factual basis or logical reason at all.

We pay a huge price in logical thinking and understanding antennas because we accept the garbage thrown out by marketing people as fact.

As for RFI, the amount of RFI we have depends on two things:

1.) Common mode impedance of the feedline systems and the impedance of the ground system at the antenna.

2.) How far the antenna is from the house, and the field strength of the antenna's fields in the house and the house wiring and consumer devices.

You can bet the ranch if a vertical antenna only has four radials per band, or even eight radials, you have a situation that can produce considerable common mode current on the coax. Now with a tuner at the antenna base, we not only have to worry about decoupling the feedline with a good common mode choke (an un-un, despite what some antenna manufacturers claim, won't change a thing for common mode) on the feeder, we have to worry about the control lead to the tuner (if it is at the antenna base).

It would be nice if 90 years of antenna design was all wrong and something as simple as a random vertical wire with a transformer would solve the world's efficiency or loss problems, but it doesn't. Most of the theory presented by marketing departments is to shift the burden and cost of building a good system on the user.

73 Tom

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