Need HF Antenna advice
 

I'm contemplating a Yaesu TF-857D with the FC-40 antenna tuner as a base
rig. I'd like to cover as many HF bands as possible with a simple wire
antenna. I'm on a small lot with an 80' tower. So anything I put up is going
to slope!

I've never used an antenna tuner before. I believe the FC-40 is weather
proof and meant for remote use.

If I slope a random wire and end-feed it, should the tuner go up on the
tower or stay on the ground? (In other words, which end should I feed?) How
should I ground the FC-40?

Anything better than a random wire that is still simple and covers all/most
of the HF bands?

--
Bob D. ND9B

Need HF Antenna advice
 

"Bob D." wrote in message
m...
I'm contemplating a Yaesu TF-857D with the FC-40 antenna tuner as a base
rig. I'd like to cover as many HF bands as possible with a simple wire
antenna. I'm on a small lot with an 80' tower. So anything I put up is
going to slope!

I've never used an antenna tuner before. I believe the FC-40 is weather
proof and meant for remote use.

If I slope a random wire and end-feed it, should the tuner go up on the
tower or stay on the ground? (In other words, which end should I feed?)
How should I ground the FC-40?

Anything better than a random wire that is still simple and covers
all/most of the HF bands?

--
Bob D. ND9B

Try this one: www.k1jek.com This is a dipole that comes in lengths of 73'
and 140' respectively. The short one covers 80-10, the longer one, 160-10
Meters, and perhaps, 6 Meters. I've had the long one for a couple of years,
and with a tuner, I've had EXCELLENT results!
With that 80 foot tower, you'd get some nice contacts!

73

Jerry

Need HF Antenna advice
 

Jerry wrote:


"Bob D." wrote in message
m...
I'm contemplating a Yaesu TF-857D with the FC-40 antenna tuner as a base
rig. I'd like to cover as many HF bands as possible with a simple wire
antenna. I'm on a small lot with an 80' tower. So anything I put up is
going to slope!

I've never used an antenna tuner before. I believe the FC-40 is weather
proof and meant for remote use.

If I slope a random wire and end-feed it, should the tuner go up on the
tower or stay on the ground? (In other words, which end should I feed?)
How should I ground the FC-40?

Anything better than a random wire that is still simple and covers
all/most of the HF bands?

--
Bob D. ND9B

Try this one: www.k1jek.com This is a dipole that comes in lengths of
73'
and 140' respectively. The short one covers 80-10, the longer one, 160-10
Meters, and perhaps, 6 Meters. I've had the long one for a couple of
years, and with a tuner, I've had EXCELLENT results!
With that 80 foot tower, you'd get some nice contacts!

73

Jerry




Hmmmm

This one seems to be another multifolded resonnator non-radiator concept
from the $hitizen bandits. If you need such bull****, there's no need to
pay buck$ for it if you can homebrew it so easily.

If you cannot afford homebrewing, then go for a real antenna! Cushcraft used
to make good multiband verticals such as the AP8A or the R7/7000-R8 series.

If you already have a "tuner" you can homebrew a 1/9 Un-Un à la ZX-Yagi MTFT
(Miracle Tranformator For Totaly-dumb-people) and hook it to your 80'
pole... Guarated under 20$ including plastic box, silvered copper wire,
inox screwery and BNC socket. For low band action you can slide a ferrite
bar in it.

73 de F8BOE Olivier ...-.-

Need HF Antenna advice
 

Bob D. wrote:

I'm contemplating a Yaesu TF-857D with the FC-40 antenna tuner as a base
rig. I'd like to cover as many HF bands as possible with a simple wire
antenna. I'm on a small lot with an 80' tower. So anything I put up is
going to slope!

I've never used an antenna tuner before. I believe the FC-40 is weather
proof and meant for remote use.

If I slope a random wire and end-feed it, should the tuner go up on the
tower or stay on the ground? (In other words, which end should I feed?)
How should I ground the FC-40?

Anything better than a random wire that is still simple and covers
all/most of the HF bands?


Hello,

By the way, there is also the OCFD (Off Cetered Fed Dipole) covering from 80
up to 10 + eventually WARCs or the Levy, but with the Levy you'll need a
specific Levy tuner... But it can be easily homebrewed.

And the antenna is one of the last part of the radio equipment we can afford
experimenting with, without spending much money (nor time).

73 de F8BOE Olivier ...-.-

Need HF Antenna advice
 

Bob D. wrote:
I'm contemplating a Yaesu TF-857D with the FC-40 antenna tuner as a base
rig. I'd like to cover as many HF bands as possible with a simple wire
antenna. I'm on a small lot with an 80' tower. So anything I put up is going
to slope!

I've never used an antenna tuner before. I believe the FC-40 is weather
proof and meant for remote use.

If I slope a random wire and end-feed it, should the tuner go up on the
tower or stay on the ground? (In other words, which end should I feed?) How
should I ground the FC-40?

Anything better than a random wire that is still simple and covers all/most
of the HF bands?

Take a look at the 88 Ft center fed Dipole. 80--10 Meters with pretty
good results. You can find out more at
http://www.cebik.com/edz/88.html
Of course you'll need a good Antenna Tuner also.

Good luck
73 Dave kc1di

Need HF Antenna advice
 

On Mon, 23 Apr 2007 22:54:09 -0400, "Bob D."
wrote:

I'm contemplating a Yaesu TF-857D with the FC-40 antenna tuner as a base
rig. I'd like to cover as many HF bands as possible with a simple wire
antenna. I'm on a small lot with an 80' tower. So anything I put up is going
to slope!

I've never used an antenna tuner before. I believe the FC-40 is weather
proof and meant for remote use.

If I slope a random wire and end-feed it, should the tuner go up on the
tower or stay on the ground? (In other words, which end should I feed?) How
should I ground the FC-40?

Anything better than a random wire that is still simple and covers all/most
of the HF bands?

I have been tinkering with an SGC-237 Tuner and I have concluded:
A tuner will match most anything.
A tuner does not change the antenna system, it only matches it.
An antenna still works best at its resonant frequency. (best is in
the eye of the beholder!)
If you use a vertical radiator against ground, the ground system is
still as important as the radiator.
Evaluating the configuration is mainly guesswork.
You can save yourself a lot of time and effort by modeling a given
configuration with EZNEC.
Your antenna begins at the connection to the tuner.

John Ferrell W8CCW
"Life is easier if you learn to
plow around the stumps"

Need HF Antenna advice
 

On Mon, 23 Apr 2007 22:54:09 -0400, "Bob D."
wrote:

I'm contemplating a Yaesu TF-857D with the FC-40 antenna tuner as a base
rig. I'd like to cover as many HF bands as possible with a simple wire
antenna. I'm on a small lot with an 80' tower. So anything I put up is going
to slope!

I've never used an antenna tuner before. I believe the FC-40 is weather
proof and meant for remote use.

If I slope a random wire and end-feed it, should the tuner go up on the
tower or stay on the ground? (In other words, which end should I feed?) How
should I ground the FC-40?

Anything better than a random wire that is still simple and covers all/most
of the HF bands?


What if he goes near the top, places the tuner there, one side to the
tower, the other side to an 80 foot wire sloped out as far as he can
go to the edge of his property, and as high as possible.?


--
73 for now
Buck, N4PGW
www.lumpuckeroo.com

Need HF Antenna advice
 

John Ferrell wrote:
An antenna still works best at its resonant frequency. (best is in
the eye of the beholder!)

"Works best" needs a definition. An Extended Double Zepp
is not resonant but "works better" than a resonant dipole
by about 3 dB broadside.
--
73, Cecil http://www.w5dxp.com

Need HF Antenna advice
 

On Mon, 23 Apr 2007 22:54:09 -0400, "Bob D."
wrote:

I'm contemplating a Yaesu TF-857D with the FC-40 antenna tuner as a base
rig. I'd like to cover as many HF bands as possible with a simple wire
antenna. I'm on a small lot with an 80' tower. So anything I put up is going
to slope!

I've never used an antenna tuner before. I believe the FC-40 is weather
proof and meant for remote use.

If I slope a random wire and end-feed it, should the tuner go up on the
tower or stay on the ground? (In other words, which end should I feed?) How
should I ground the FC-40?

Anything better than a random wire that is still simple and covers all/most
of the HF bands?

A simple end fed wire is complicated by the fact that it will need a
good ground system.

A sloping dipole, or an inverted V dipole coming off your 80 foot
tower, will need no ground system, though. So the dipole might be
easier.

bob
k5qwg

Need HF Antenna advice
 

Cecil Moore writes:

John Ferrell wrote:
An antenna still works best at its resonant frequency. (best is in
the eye of the beholder!)

"Works best" needs a definition. An Extended Double Zepp
is not resonant but "works better" than a resonant dipole
by about 3 dB broadside.

Once it's up, you can't rotate it. Whether the gain and the nulls are
a net advantage or not depends on the application.

73
LA4RT Jon

Need HF Antenna advice
 

LA4RT Jon Kåre Hellan wrote:
Once it's up, you can't rotate it.

I have a 10m rotatable EDZ about which I wrote a
magazine article entitled, "Who Needs A Beam?".
--
73, Cecil http://www.w5dxp.com

Need HF Antenna advice
 

Cecil Moore writes:

LA4RT Jon KÃ¥re Hellan wrote:
Once it's up, you can't rotate it.

I have a 10m rotatable EDZ about which I wrote a
magazine article entitled, "Who Needs A Beam?".

*Blush*

Need HF Antenna advice
 

"F8BOE" wrote in message
...
Jerry wrote:


"Bob D." wrote in message
m...
I'm contemplating a Yaesu TF-857D with the FC-40 antenna tuner as a base
rig. I'd like to cover as many HF bands as possible with a simple wire
antenna. I'm on a small lot with an 80' tower. So anything I put up is
going to slope!

I've never used an antenna tuner before. I believe the FC-40 is weather
proof and meant for remote use.

If I slope a random wire and end-feed it, should the tuner go up on the
tower or stay on the ground? (In other words, which end should I feed?)
How should I ground the FC-40?

Anything better than a random wire that is still simple and covers
all/most of the HF bands?

--
Bob D. ND9B

Try this one: www.k1jek.com This is a dipole that comes in lengths of
73'
and 140' respectively. The short one covers 80-10, the longer one,
160-10
Meters, and perhaps, 6 Meters. I've had the long one for a couple of
years, and with a tuner, I've had EXCELLENT results!
With that 80 foot tower, you'd get some nice contacts!

73

Jerry




Hmmmm

This one seems to be another multifolded resonnator non-radiator concept
from the $hitizen bandits. If you need such bull****, there's no need to
pay buck$ for it if you can homebrew it so easily.

If you cannot afford homebrewing, then go for a real antenna! Cushcraft
used
to make good multiband verticals such as the AP8A or the R7/7000-R8
series.

If you already have a "tuner" you can homebrew a 1/9 Un-Un à la ZX-Yagi
MTFT
(Miracle Tranformator For Totaly-dumb-people) and hook it to your 80'
pole... Guarated under 20$ including plastic box, silvered copper wire,
inox screwery and BNC socket. For low band action you can slide a ferrite
bar in it.

73 de F8BOE Olivier ...-.-

Sir, I've built more antennas since 1964 than you can count. Including
scewdrivers (www.qsl.net/k4kwh) In this case, the one I recommended (since
he didn't say specifically) was because I had some illness/death at home, I
wanted to cover 160 Meters in a small lot, and I couldn't devote the time to
building an antenna at the time. I beg to differ with the non-radiator
antenna comment. KNOW of which you speak.........like actually reading the
reviews of it on www.eham.net.
There ARE reasons for the choices we make! The Cobra WORKS, and next time,
yeah, I will probably make one as I now have the time I did not have prior
to my Father's illness and death!!! :(

Need HF Antenna advice
 

"Jerry" wrote in
:

....
Try this one: www.k1jek.com This is a dipole that comes in lengths
of 73' and 140' respectively. The short one covers 80-10, the longer

Ah, the Cobra! An interesting antenna for exploration of the myth that
linear loading is essentially lossless, see my analysis of NEC models of a
Cobra design at http://www.vk1od.net/cobra/index.htm .

Owen

Need HF Antenna advice
 

"Owen Duffy" wrote in message
...
"Jerry" wrote in
:

...
Try this one: www.k1jek.com This is a dipole that comes in lengths
of 73' and 140' respectively. The short one covers 80-10, the longer

Ah, the Cobra! An interesting antenna for exploration of the myth that
linear loading is essentially lossless, see my analysis of NEC models of a
Cobra design at http://www.vk1od.net/cobra/index.htm .

Owen

Says "Page not found"!


JWO

Need HF Antenna advice
 

On Wed, 25 Apr 2007 22:45:33 -0400, "Jerry"
wrote:


"Owen Duffy" wrote in message
...
"Jerry" wrote in
:

...
Try this one: www.k1jek.com This is a dipole that comes in lengths
of 73' and 140' respectively. The short one covers 80-10, the longer

Ah, the Cobra! An interesting antenna for exploration of the myth that
linear loading is essentially lossless, see my analysis of NEC models of a
Cobra design at http://www.vk1od.net/cobra/index.htm .

Owen

Says "Page not found"!


JWO


Works okay for me. Nice paper ( I stole the NEC deck).

Danny, K6MHE

Need HF Antenna advice
 

Danny Richardson wrote in
:

....
Works okay for me. Nice paper ( I stole the NEC deck).

Hi Danny,

You will see that the FR card has a symbolic variable for the frequency,
you will need to feed it a float value. (I used a PERL script to run a
series of models by tailoring the basic NEC deck, executing it, and
summarising the results.)

Differently to many of the commercial Cobras, my model used 2mm dia
copper and wider spacing. Most seem to use smaller, even very small
spacings where proximity effect becomes significant, smaller conductors,
and possibly steel cored copper clad conductors.

IMHO, the interesting aspect of the article is the loss mechanism of
linear loading, it makes sense once you see the current magnitudes and
phase and realise this thing at some frequencies carries large conductor
currents for low net current moment.

I have been exploring a 13m unloaded vertical with 2 radials for each of
80, 40, 30, & 20 metre bands, and there is a different but similar (!!!)
effect where at some frequencies the radials carry large individual
currents (larger in magnitude than the current in the vertical) with a
peak in loss at these frequencies, see
http://www.vk1od.net/multibandunload...al/13mEV-1.gif .

Owen

Need HF Antenna advice
 

On Thu, 26 Apr 2007 03:34:29 GMT, Owen Duffy wrote:

Danny Richardson wrote in
:

...
Works okay for me. Nice paper ( I stole the NEC deck).

Hi Danny,

You will see that the FR card has a symbolic variable for the frequency,
you will need to feed it a float value. (I used a PERL script to run a
series of models by tailoring the basic NEC deck, executing it, and
summarising the results.)

[snip]

Owen

No problem Owen, I'll use MultiNec which very easily allows me to run
"test cases" using variables with no programming required on my part.
G.

Danny

Need HF Antenna advice
 

Danny Richardson wrote in
:
....
No problem Owen, I'll use MultiNec which very easily allows me to run
"test cases" using variables with no programming required on my part.

Ok. There are other tools that allow symbolic variables, and of course NEC
allows specification of a range of frequencies on the FR card.

The main reason for using PERL to build, run and sumamrise is the summarise
stage. At that point I merge the NEC output with real transmission line
models, L-tuner models etc... and without wading through 5MB of NEC output
by hand. The system view is a bigger picture than the NEC output.

Owen

Need HF Antenna advice
 

Jerry wrote:
"Owen Duffy" wrote:
http://www.vk1od.net/cobra/index.htm .

Says "Page not found"!

Worked for me.
--
73, Cecil http://www.w5dxp.com

Need HF Antenna advice
 

"Cecil Moore" wrote in message
...
Jerry wrote:
"Owen Duffy" wrote:
http://www.vk1od.net/cobra/index.htm .

Says "Page not found"!

Worked for me.
--
73, Cecil http://www.w5dxp.com

Musta been a temporary thing. Worked shortly after I tried it again.

BTW, for whatever shortcomings Joe's Cobra has, I've had excellent results
and been complimented both on the ham bands and on some other
military/non-amateur frequencies I am authorized from 2-22 MHZ. So long as
it works! I'll probably do something else later, but at the time, the Cobra
was the best considering personal considerations and lot limitations. And,
actually, I am not one of those who must have the biggest signal going--just
so you can hear me well enough to do the job! ;)

73

Jerry

Need HF Antenna advice
 

"Jerry" wrote in
:


"Cecil Moore" wrote in message
...
Jerry wrote:
"Owen Duffy" wrote:
http://www.vk1od.net/cobra/index.htm .

Says "Page not found"!

Worked for me.
--
73, Cecil http://www.w5dxp.com

Musta been a temporary thing. Worked shortly after I tried it again.

BTW, for whatever shortcomings Joe's Cobra has, I've had excellent
results and been complimented both on the ham bands and on some other
military/non-amateur frequencies I am authorized from 2-22 MHZ. So
long as it works! I'll probably do something else later, but at the
time, the Cobra was the best considering personal considerations and
lot limitations. And, actually, I am not one of those who must have
the biggest signal going--just so you can hear me well enough to do
the job! ;)

Jerry, it seems to me that the Cobra is a compromise, and we each make
our own judgements about the trade-offs that are acceptable. Of course,
those individual considerations make recomendations like "it works great
for me, it is the best for you" rather worthless.

Some of the claims about some antennas (including the Cobra) seem
unrealistic, but that doesn't condemn the antennas, it just means people
building or buying them based on those claims have been mislead.

It is my view that understanding the behaviour of the antennas helps you
to make an informed judgement about the trade-offs in your own situation,
and it allows you to get the best out of the antenna as installed.

Modelling suggests that the Cobra Jnr has a couple of weaknesses, one is
the spikes in loss at some frequencies (an artefact of linear loading),
most but not all of which are outside amateur bands; and the second is
that the "window" of low loss around 80m is narrow and might be worth
checking that as installed, that window is centred over your most
desirable operating frequncies. These effects scaled for the double size
are more pronounced with the full sized Cobra.

An effect similar to the second point above exists also with the G5RV,
and I have suggested a procedure in-situ tuning for optimising 80m
performance. If I had a full sized Cobra and intended using it on 160m,
or a Cobra Jnr on 80m, I certainly would think about doing similar.

Owen