Sources for Inexpensive RG-8??
 

I'll have some fairly long runs of coax to HF antennas (21Mhz max) to
Field Day antennas. One of the antennas will be an 80M G5RV with their
usual nasty SWRs so a foam-type cable is indicated. Since it's a very
temporary non-critical installation I'm not about to spend premium
bucks on 9913 or any of it's relatives like I do for the home station.
A non-contaminating jacket would be nice but is not much of an issue.
Does anybody have any suggestions about vendors who are selling foam
RG-8 for lower-than-usual prices?

Thanks, Brian w3rv

On 2 Apr 2004 07:38:00 -0800, Brian Kelly wrote:

I'll have some fairly long runs of coax to HF antennas (21Mhz max) to
Field Day antennas. One of the antennas will be an 80M G5RV with their
usual nasty SWRs so a foam-type cable is indicated. Since it's a very
temporary non-critical installation I'm not about to spend premium
bucks on 9913 or any of it's relatives like I do for the home station.
A non-contaminating jacket would be nice but is not much of an issue.
Does anybody have any suggestions about vendors who are selling foam
RG-8 for lower-than-usual prices?

Thanks, Brian w3rv

Could you get hold of 75 ohm cable instead? G5RV recommended it for this
antenna anyway and regardless of what you use you will need a tuner.
RG 59 may be cheaper and CATV cable may be free or someone may have enough
to help you out.
73 de VE3JUA.

Brian Kelly wrote:
I'll have some fairly long runs of coax to HF antennas (21Mhz max) to
Field Day antennas. One of the antennas will be an 80M G5RV with their
usual nasty SWRs so a foam-type cable is indicated.

Hi Brian, what bands will the G5RV be used on? Only 80m?
The SWR is not all that nasty on 80m being about 20:1
on the ladder-line and 2:1 on the coax.

Here's one of my rules-of-thumb for which I am infamous. :-)

Given a 102 ft. Dipole at 40 ft. fed with 450 ohm ladder-line
and used on 3.8 MHz, for a ladder-line length between about
25 ft. and 100 ft., the resistance looking into the ladder-line
is about equal to the length of the ladder-line. Thus for 25 ft.
of ladder-line, the impedance looking into the ladder-line is
about 25+jXL1. For a ladder-line length of 50 ft., the impedance
looking into the ladder-line is about 50+jXL2. For a ladder-line
length of 100 ft., the impedance looking into the ladder-line
is about 100+jXL3. Does that give you any hints on how to match it?

According to EZNEC, the impedance looking into 50 ft. of ladder-line
is about 50+j466. Use two series 180pf caps to neutralize the inductive
reactance and you have a feedpoint impedance of 50 ohms. A dual ganged
300pf variable would be ideal.

A 102 ft dipole 40 feet in the air fed with 50 ft of ladder-line
tuned with a dual-gang variable cap on the antenna side of a balun/
choke and no tuner box. Doesn't that sound like a perfect 75m field
day antenna?
--
73, Cecil, W5DXP

Cecil Moore wrote:
Given a 102 ft. Dipole at 40 ft. fed with 450 ohm ladder-line
and used on 3.8 MHz, for a ladder-line length between about
25 ft. and 100 ft., the resistance looking into the ladder-line
^^^^^^^
is about equal to the length of the ladder-line. Thus for 25 ft.
of ladder-line, the impedance looking into the ladder-line is
about 25+jXL1. For a ladder-line length of 50 ft., the impedance
looking into the ladder-line is about 50+jXL2.

I misspoke above. "100 ft." should have been "50 ft."

For a ladder-line
length of 100 ft., the impedance looking into the ladder-line
is about 100+jXL3.

It is true that the resistance for 100 ft. of ladder-line is about
100 ohms, but it is 100-jXC, not 100+jXL. Sorry for the faulty memory.
--
73, Cecil, W5DXP

Cecil Moore wrote in message

A 102 ft dipole 40 feet in the air fed with 50 ft of ladder-line
tuned with a dual-gang variable cap on the antenna side of a balun/
choke and no tuner box. Doesn't that sound like a perfect 75m field
day antenna?

I hope you are successful in making people think so. :/ It'll be
easier pickings for me and my superior, lower overall loss, radiating
device. :) I already use the *perfect* 75m field day antenna. It's a
regular old full size coax fed dipole. Why would anyone want to
clutter up low loss perfection? Boggles my mind...:/ But it's ok, like
I said, it's to my advantage on that bug infested night in June. I
hope everyone else is using G5RV's, windoms, isotrons, EH's and other
such things.. Makes it easier for us. .:) MK

Mark Keith wrote:
Cecil Moore wrote in message

A 102 ft dipole 40 feet in the air fed with 50 ft of ladder-line
tuned with a dual-gang variable cap on the antenna side of a balun/
choke and no tuner box. Doesn't that sound like a perfect 75m field
day antenna?

I hope you are successful in making people think so. :/ It'll be
easier pickings for me and my superior, lower overall loss, radiating
device. :) I already use the *perfect* 75m field day antenna. It's a
regular old full size coax fed dipole. Why would anyone want to
clutter up low loss perfection? Boggles my mind...:/ But it's ok, like
I said, it's to my advantage on that bug infested night in June. I
hope everyone else is using G5RV's, windoms, isotrons, EH's and other
such things.. Makes it easier for us. .:) MK

I suspect the above antenna is more efficient than your coax-fed dipole.
There's negligible loss in the 50 ft. of ladder-line and negligible loss
in the series caps. No tuner required, therefore no lossy coil. So where's
the loss? Please be specific and provide data to back it up.
--
73, Cecil, W5DXP



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Cecil Moore wrote in message

I suspect the above antenna is more efficient than your coax-fed dipole.
There's negligible loss in the 50 ft. of ladder-line and negligible loss
in the series caps. No tuner required, therefore no lossy coil. So where's
the loss? Please be specific and provide data to back it up.

I suspect you would be in for a surprise at field day..
What about your balun/choke connection? I assume you will be running
coax to that choke, and then to 50 ft of ladder line? And the variable
cap on the antenna side of the choke...How convenient... All I can say
is why? There is no way on earth that setup is *more* efficient than a
coax fed dipole. It may be *fairly* efficient, maybe even quite so if
you are real lucky, but it's not going to be as good as the full size
dipole fed with good coax. No way. The only real loss I have is the
loss of the feedline "213", and on 80m, it's about as good as ladder
line.
Dunno...I think complicated gimmicky setups that are inferior to the
ultra simple coax fed dipole are kind of silly. :/ But to each his
own. If it were better, I could see it. But it's not. It's inferior.
If it were not, I would be using one here at the house. Why would
anyone want to do more work, for something a step in the wrong
direction? Boggles me mind...I've never seen why people want to use
smaller or compromise antennas when you have the whole wide outdoors
to string up anything you want. The "average" storebought G5RV is
pitiful on 80m compared to the coax fed dipole. Not even a real
contest.
But everyone ignore what I say. I'm really fibbing, and just messing
with ole Cecils head....I suggest all field day op's on 80m use
G5RV's, windoms, isotrons and EH antennas. If you all follow my
advice, I might be able to mop up quick, and be able to go home early
and get some sleep in my cool, bug free, air conditioned bed.. :/ MK

Mark Keith wrote:
What about your balun/choke connection?

W2DU choke, virtually lossless. The tuning cap is also virtually
lossless, much more so than a tuner with a coil.

The only real loss I have is the
loss of the feedline "213", and on 80m, it's about as good as ladder
line.

It's about as good as open-wire line with a 10:1 SWR. The matched line
losses in 100 ft. of RG-213 are higher than the unmatched line losses
in 100 ft. of open-wire line with a 10:1 SWR on 80m.

According to Wirebook II, the matched line loss for RG-213 is ten
times higher on 80m than the matched line loss for open-wire line.

If it were better, I could see it. But it's not. It's inferior.
If it were not, I would be using one here at the house.

You are so biased, you wouldn't use one if your life depended
on it. :-)

Why would
anyone want to do more work, for something a step in the wrong
direction?

It's a step in the right direction, Mark, toward an all-HF-band
antenna. I modified my G5RV yesterday to work well on all eight
HF bands plus 6m. Field strength measurements indicated it is
virtually identical to my 130 foot dipole on 80m.

The "average" storebought G5RV is
pitiful on 80m compared to the coax fed dipole.

Mine is virtually equal to a resonant dipole. Your "average" storebought
G5RV must be poorly designed - maybe lacking a balun - maybe using RG-58
coax - maybe using the wrong length of the series section transformer.

But everyone ignore what I say. I'm really fibbing, and just messing
with ole Cecils head...

I asked for some scientific proof of what you say. All you responded
with is prejudice and hand-waving. Please take time to calculate
the matched line losses in RG-213 Vs the unmatched line losses for
open-wire line and you will change your mind (if you are rational).
--
73, Cecil, W5DXP



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Cecil Moore wrote in message ...
Brian Kelly wrote:
I'll have some fairly long runs of coax to HF antennas (21Mhz max) to
Field Day antennas. One of the antennas will be an 80M G5RV with their
usual nasty SWRs so a foam-type cable is indicated.

Hi Brian, what bands will the G5RV be used on? Only 80m?
The SWR is not all that nasty on 80m being about 20:1
on the ladder-line and 2:1 on the coax.

Greetings Cecil: I've been on the road for the past three days and am
just now catching up with my e-mail and such.

The answer to your question is that I intend to use a Van Gordon 80M
G5RV at about 40 ft. on 80/75/40 as a minimum. I'm "ambidextrous", I
motor-mouth and twitch paddles on FD so I need "bandwidth" on 80/75.
I'm building a close-spaced wires duo-band dipole for 20 & 15 which
will be hung at around 25-30 ft. If that antenna doesn't work right
I'll also have to use the G5RV on 20/15 too. In the ideal scenario
both antennas would work and I'll be able to swap antennas around for
20 & 15 depending on the pattern & propagation condx of the moment.
I'll use 8X to feed the G5RV balun which will be 8-10 foot above
ground level to keep the weight on the G5RV down

From there I'll run a length of RG-8 to the operating position. Looks
like a 75 or so foot run. I'll use my LDG-11MP ATU to tame the G5RV.
With all this coax involved the ATU won't have much "work" to do . . .

Here's one of my rules-of-thumb for which I am infamous. :-)

Heh.

Given a 102 ft. Dipole at 40 ft. fed with 450 ohm ladder-line
and used on 3.8 MHz, for a ladder-line length between about
25 ft. and 100 ft., the resistance looking into the ladder-line
is about equal to the length of the ladder-line. Thus for 25 ft.
of ladder-line, the impedance looking into the ladder-line is
about 25+jXL1. For a ladder-line length of 50 ft., the impedance
looking into the ladder-line is about 50+jXL2. For a ladder-line
length of 100 ft., the impedance looking into the ladder-line
is about 100+jXL3. Does that give you any hints on how to match it?

According to EZNEC, the impedance looking into 50 ft. of ladder-line
is about 50+j466. Use two series 180pf caps to neutralize the inductive
reactance and you have a feedpoint impedance of 50 ohms. A dual ganged
300pf variable would be ideal.

A 102 ft dipole 40 feet in the air fed with 50 ft of ladder-line
tuned with a dual-gang variable cap on the antenna side of a balun/
choke and no tuner box. Doesn't that sound like a perfect 75m field
day antenna?

I've read the whole thread thru Tuesday AM, I get your point and it
should work well on 80. I suspect the real advantage of your scheme is
that it might be possible to cover both 80 and 75 with low overall
losses which is difficult to accomplish with a fullsize dipole. Since
you already have the EZNec model on hand how 'bout running a 3.50-3.85
Mhz. sweep to see if it's possible to cover that range with some
single specific length of ladderline and the two-section BC variable
cap? If yes I think you have a real keeper idea.

Davis RF has "RG-213 Economy" cable, whatever that is, for $0.23/foot.
Good enough for Field Day.

Brian w3rv

Eskay wrote in message ...
On 2 Apr 2004 07:38:00 -0800, Brian Kelly wrote:

I'll have some fairly long runs of coax to HF antennas (21Mhz max) to
Field Day antennas. One of the antennas will be an 80M G5RV with their
usual nasty SWRs so a foam-type cable is indicated. Since it's a very
temporary non-critical installation I'm not about to spend premium
bucks on 9913 or any of it's relatives like I do for the home station.
A non-contaminating jacket would be nice but is not much of an issue.
Does anybody have any suggestions about vendors who are selling foam
RG-8 for lower-than-usual prices?

Thanks, Brian w3rv

Could you get hold of 75 ohm cable instead? G5RV recommended it for this
antenna anyway and regardless of what you use you will need a tuner.
RG 59 may be cheaper and CATV cable may be free or someone may have enough
to help you out.

Using 75 ohm coax is probably a good idea, I'll look into it. But I
don't want to use any small-diameter coax, the losses would be
prohibitive considering the lengths of runs I'll use.


73 de VE3JUA.

Brian w3rv

Cecil Moore wrote in message ...
Mark Keith wrote:
What about your balun/choke connection?

W2DU choke, virtually lossless. The tuning cap is also virtually
lossless, much more so than a tuner with a coil.

Won't this depend on the match involved? I have trouble seeing that
connection as "virtually lossless".

The only real loss I have is the
loss of the feedline "213", and on 80m, it's about as good as ladder
line.

It's about as good as open-wire line with a 10:1 SWR. The matched line
losses in 100 ft. of RG-213 are higher than the unmatched line losses
in 100 ft. of open-wire line with a 10:1 SWR on 80m.

Sure, but is it enough to notice on the air? I doubt it...

According to Wirebook II, the matched line loss for RG-213 is ten
times higher on 80m than the matched line loss for open-wire line.

If it were better, I could see it. But it's not. It's inferior.
If it were not, I would be using one here at the house.

You are so biased, you wouldn't use one if your life depended
on it. :-)

You got that right. Nothing but the best for me.

Why would
anyone want to do more work, for something a step in the wrong
direction?

It's a step in the right direction, Mark, toward an all-HF-band
antenna.
Who's talking about all band use though? All I've heard mentioned was
80m.

I modified my G5RV yesterday to work well on all eight
HF bands plus 6m. Field strength measurements indicated it is
virtually identical to my 130 foot dipole on 80m.

Virtually huh....

The "average" storebought G5RV is
pitiful on 80m compared to the coax fed dipole.

Mine is virtually equal to a resonant dipole.

Maybe close...
Your "average" storebought
G5RV must be poorly designed -

It was.

maybe lacking a balun -

Nope, it had one. I always considered that choke/balun half the
problem...

maybe using RG-58
coax - maybe using the wrong length of the series section transformer.

No, it was RG-8. The antenna was a common storebought version. I won't
mention names, but it's the most popular version out there.

But everyone ignore what I say. I'm really fibbing, and just messing
with ole Cecils head...

I asked for some scientific proof of what you say. All you responded
with is prejudice and hand-waving. Please take time to calculate
the matched line losses in RG-213 Vs the unmatched line losses for
open-wire line and you will change your mind (if you are rational).

Why? I've already done it. I don't need those numbers to help make up
my mind. I've compared the real antennas. I'll never change my mind.
Nothing but the best for me. Anything less is a waste of my valuable
time. All bands? Who gives a rats rectum about all band use? We have
three tri band yagi's for the higher bands. Will smoke any G5RV used
on those bands...Well, time to unplug..It's lightning time for
nm5k...MK

Mark Keith wrote:

Cecil Moore wrote:
W2DU choke, virtually lossless. The tuning cap is also virtually
lossless, much more so than a tuner with a coil.

Won't this depend on the match involved? I have trouble seeing that
connection as "virtually lossless".

I feed all my antennas at a low resistance current maximum point so the
W2DU choke is indeed virtually lossless and fully functional to boot
because it is seeing its designed-for resistance. You would know that
if you took time off from your prejudice position to actually think. :-)

It's about as good as open-wire line with a 10:1 SWR. The matched line
losses in 100 ft. of RG-213 are higher than the unmatched line losses
in 100 ft. of open-wire line with a 10:1 SWR on 80m.

Sure, but is it enough to notice on the air? I doubt it...

If it's not enough to notice on the air, doesn't your entire point
evaporate into nothingness? If no one notices whether an antenna is
resonant or not or fed with coax or open-wire line, what is the point
of your argument?

Why? I've already done it. I don't need those numbers to help make up
my mind. I've compared the real antennas. I'll never change my mind.

That's pretty obvious and is a trait shared by the Catholic Priests who
condemned Copernicus and Galileo. I believe you will never change your
mind even if you come over to my house and see scientific evidence to the
contrary. It's a good thing human lifespans are so short or else the human
race would never make any technical progress.
--
73, Cecil, W5DXP



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Cecil Moore wrote:

Mark Keith wrote:

Cecil Moore wrote:
W2DU choke, virtually lossless. The tuning cap is also virtually
lossless, much more so than a tuner with a coil.

Won't this depend on the match involved? I have trouble seeing that
connection as "virtually lossless".

I feed all my antennas at a low resistance current maximum point so the
W2DU choke is indeed virtually lossless and fully functional to boot
because it is seeing its designed-for resistance. You would know that
if you took time off from your prejudice position to actually think. :-)

How many others feed theirs this way? How would I know how yours would
vary from the "usual G5RV"?


If it's not enough to notice on the air, doesn't your entire point
evaporate into nothingness?

No. That is only comparing using coax to ladder line with no other
considerations given.

If no one notices whether an antenna is
resonant or not or fed with coax or open-wire line, what is the point
of your argument?

Because I DO notice the difference between a coax fed dipole and either
a G5RV or the usual "windom" that is sold by "eastern state antenna co.
inc"

Why? I've already done it. I don't need those numbers to help make up
my mind. I've compared the real antennas. I'll never change my mind.

That's pretty obvious and is a trait shared by the Catholic Priests who
condemned Copernicus and Galileo. I believe you will never change your
mind even if you come over to my house and see scientific evidence to the
contrary. It's a good thing human lifespans are so short or else the human
race would never make any technical progress.

Cecil, you might have a modified G5RV that is fairly usable, but most of
the ones that are actually sold, and are in use, are lame 80m antennas
to my standards. Same for the average windom, or OCF dipole. This is
not idle speculation. I've A/B compared them at field days. I started
doing this after getting stuck on G5RV's on 80m for two years in a row.
"What torture..I almost pulled my hair out :( ..."
The owner of one windom I tested against had no idea what he was losing
until I showed him. He almost fell over at the 2-3 S unit differences we
saw when flipping the switch... To answer one earlier question for you,
my feedline loss at 4 mhz is .4 db for 100 ft of line at the most. Other
than my ground loss, which will be the same for either types of
antennas, for all practical purposes I have no loss.
You can not detect .4 db difference in the real world on 80m. And being
I'll be at 3.500, it will be slightly less. And if I don't use the full
100ft, it will be even less.
When directly comparing the coax fed dipole to the commonly used
"windom" that is sold by said ESA inc., the dipole was better on all
signals , including just the atmospheric noise floor by a min of 2 S
units. This increase is not pattern related. It's purely a difference in
feeder efficiency. And that was on 40m, not 80. On 80m, it probably
would have been a greater difference.
Now, Cecil, do the math. How many db difference does it take to measure
2 s units on the average radio? A lot more that .4 db, I can tell you.
On 80m, the "storebought" G5RV's we tried were the lousiest 80m antennas
I've ever used without going to a hamstick on a VW. Yes, I do have high
standards! I've only used full size antennas my whole 80m life... When
you are running 100w, but have the performance of QRP, field day is not
fun for me. You say I'm exaggerating? How many db drop will you see on
the average radio's S meter if you drop 10 db? About 2 maybe ? The
difference between the funky G5RV's we used, and a dipole on 80m were
2-3 S units easy. You may have modified yours to improve it, but I still
don't want one. Thanks, but no thanks...
I only use full size antennas unless it's impossible. 80m on field day
is ruff cdx. Noisiest time of the year, and the band is packed wall to
wall. No place for compromise antennas..:)
But to each his own...Like I say, the more that use those things, the
easier I'll have it. Well, except I have to strain my ears more when
working those stations...:/ MK

--
http://web.wt.net/~nm5k

Brian Kelly wrote:
I've read the whole thread thru Tuesday AM, I get your point and it
should work well on 80. I suspect the real advantage of your scheme is
that it might be possible to cover both 80 and 75 with low overall
losses which is difficult to accomplish with a fullsize dipole. Since
you already have the EZNec model on hand how 'bout running a 3.50-3.85
Mhz. sweep to see if it's possible to cover that range with some
single specific length of ladderline and the two-section BC variable
cap? If yes I think you have a real keeper idea.

Maybe you'll like this one. 110 ft dipole at 40 ft, fed with 110 ft of
450 ohm ladder-line and tuned with a single control dual-gang variable cap,
i.e. no conventional antenna tuner. Such an antenna system covers the entire
75-80m band with a 50 ohm SWR ranging from 1.7 at 3.5 MHz to 1.0 at 4.0 MHz,
according to EZNEC. Full band coverage at the twist of one knob? You likeie?

For a coax fed dipole, EZNEC reports an SWR=2:1 bandwidth of 170 kHz.
--
73, Cecil, W5DXP



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Mark Keith wrote:
How many others feed theirs this way?

I don't know and don't much care. The discussion is about your
antenna Vs mine.

How would I know how yours would vary from the "usual G5RV"?

By the length of the series section transformer. It varies from
20 ft on 10.125 MHz to 35 ft on 18.14 MHz providing less than
2:1 SWR on the coax on all HF bands - no tuner required. On 3.8 MHz
with a series section length of 23 ft, the series section feedpoint
impedance is resonant at 25+j0 ohms.

Because I DO notice the difference between a coax fed dipole and either
a G5RV or the usual "windom" that is sold by "eastern state antenna co.
inc"

Theirs are not optimumized - mine is. Why don't you compare your dipole
to an Isotron so you can feel even better. :-)

Other than my ground loss, which will be the same for either types of
antennas, for all practical purposes I have no loss.

I can say exactly the same thing. My 50 ohm SWR is less than 2:1 without
a tuner of any kind. There's simply no places for losses to occur.

You can not detect .4 db difference in the real world on 80m.

So if my antenna is within .4 dB of yours, it's as good as yours?
I wish I had said that. As a matter of fact, the difference between
your antenna and mine is the difference between an SWR of 1:1 and an
SWR of 2:1 on 75m. The ARRL Handbook loss chart says that is 0.12 dB
difference for 100 ft of RG-213 on 75m.

Now, Cecil, do the math.

There it is in the paragraph above. My dipole is 102 ft long. EZNEC sez
it has a maximum gain of 6.04 dBi compared to 6.24 dBi for your dipole.
Including the 0.2 dB reduction in gain and the 0.12 dB of additional
losses in the coax for an SWR of 2:1, that's 0.32 dB modeled difference
between your dipole and my G5RV and you say one cannot detect a 0.4 dB
difference. Doesn't that shoot your own argument down?

How many db difference does it take to measure
2 s units on the average radio? A lot more that .4 db, I can tell you.

I'll bet $100 that your antenna is NOT anywhere near 2 S-units better than
mine on 3.8 MHz. And I'll bet my antenna is 2 S-units better than your coax
fed 80m dipole on most bands between 40m and 10m where it functions as well
or better than it does on 75m.
--
73, Cecil, W5DXP



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Cecil Moore wrote in message ...
Mark Keith wrote:
How many others feed theirs this way?

I don't know and don't much care. The discussion is about your
antenna Vs mine.

Well, maybe at this point, but not previously. I have had no idea what
you do to your antenna. I'm talking about G5RV's in general. Mainly
the goofy storebought versions.

How would I know how yours would vary from the "usual G5RV"?

By the length of the series section transformer. It varies from
20 ft on 10.125 MHz to 35 ft on 18.14 MHz providing less than
2:1 SWR on the coax on all HF bands - no tuner required. On 3.8 MHz
with a series section length of 23 ft, the series section feedpoint
impedance is resonant at 25+j0 ohms.

You missed the question...How would I know you do that unless you tell
me in advance...I'm not a mind reader...

Because I DO notice the difference between a coax fed dipole and either
a G5RV or the usual "windom" that is sold by "eastern state antenna co.
inc"

Theirs are not optimumized - mine is. Why don't you compare your dipole
to an Isotron so you can feel even better. :-)

I have. Gives me a woody....:) I've compared the coax fed dipole to
everything on 80m. So far, it's never lost a race. To anything. Only
slightly improved by converting to a turnstile maybe...:/


Other than my ground loss, which will be the same for either types of
antennas, for all practical purposes I have no loss.

I can say exactly the same thing. My 50 ohm SWR is less than 2:1 without
a tuner of any kind. There's simply no places for losses to occur.

You can not detect .4 db difference in the real world on 80m.

So if my antenna is within .4 dB of yours, it's as good as yours?

Yes. IF...But I will still prefer the coax fed dipole.

I wish I had said that. As a matter of fact, the difference between
your antenna and mine is the difference between an SWR of 1:1 and an
SWR of 2:1 on 75m. The ARRL Handbook loss chart says that is 0.12 dB
difference for 100 ft of RG-213 on 75m.

Now, Cecil, do the math.

There it is in the paragraph above. My dipole is 102 ft long. EZNEC sez
it has a maximum gain of 6.04 dBi compared to 6.24 dBi for your dipole.
Including the 0.2 dB reduction in gain and the 0.12 dB of additional
losses in the coax for an SWR of 2:1, that's 0.32 dB modeled difference
between your dipole and my G5RV and you say one cannot detect a 0.4 dB
difference. Doesn't that shoot your own argument down?

No. Your antenna is different than the vast majority used if what you
say is true.

How many db difference does it take to measure
2 s units on the average radio? A lot more that .4 db, I can tell you.

I'll bet $100 that your antenna is NOT anywhere near 2 S-units better than
mine on 3.8 MHz. And I'll bet my antenna is 2 S-units better than your coax
fed 80m dipole on most bands between 40m and 10m where it functions as well
or better than it does on 75m.

If you have improved yours, I'm glad. You may well have a decent
antenna. But you need to spread the word, because most other's that
are unmodified are still gonna be lame radiators. What proposal do you
offer to correct the feedline deficiencies of the average storebought
windom, or OCF dipole on 40 and 80m? They need your help too. If you
all get your heads together, you might be able give me some rf
competition this year... :) MK

Mark Keith wrote:

Cecil Moore wrote:
I don't know and don't much care. The discussion is about your
antenna Vs mine.

Well, maybe at this point, but not previously.

The argument has always been about your coax-fed dipole antenna
Vs my G5RV antenna.

You missed the question...How would I know you do that unless you tell
me in advance...I'm not a mind reader...

My antenna is a G5RV. You said your dipole would beat "any" G5RV,
presumably including mine. Your ignorance of my G5RV didn't enter
into the discussion at the time. You didn't even slow down to wonder
if a well-designed G5RV might equal your dipole on 75m.

Yes. IF...But I will still prefer the coax fed dipole.

If the design flaws of the G5RV are fixed, we then shift from
performance to preference?

Your antenna is different than the vast majority used if what you
say is true.

It's a well-designed G5RV, the best I know of. You said you dipole would
beat "any" G5RV by S-units.

If you have improved yours, I'm glad. You may well have a decent
antenna. But you need to spread the word, because most other's that
are unmodified are still gonna be lame radiators.

I posted my actual measurements yesterday. To optimize a G5RV for 75m,
make the series section transformer 25 feet long and put a 1000 pf
capacitor in parallel at the coax/open-wire junction. The beauty is
that you still have the framework for an all-HF-band antenna. Take
away the cap and extend the series section to 36 feet and you have
a G5RV optimized for 40m and 17m, my favorite bands. It takes about
two minutes for me to make that change but it could be automated.

What proposal do you
offer to correct the feedline deficiencies of the average storebought
windom, or OCF dipole on 40 and 80m?

The original windom, powered by a tube transmitter with a pi-net matching
network, was a pretty good antenna. For today's "Windoms", I would advise
everyone to feed OCF's with open-wire line, equipped with an excellent
choke, at a current maximum point, using whatever ratio balun is appropriate.
I had an OCF in college, fed with open-wire line, powered by a Heathkit with
a pi-net tuning network. It's feedpoint impedance on the harmonically related
bands was in the neighborhood of 300 ohms. Matching a tube final to 300 ohms
through a pi-net tuner is pretty much a no-brainer and relatively lossless.
--
73, Cecil, W5DXP



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On Wed, 07 Apr 2004 15:57:41 -0500, Cecil Moore hath writ:
Mark Keith wrote:

Cecil Moore wrote:
I don't know and don't much care. The discussion is about your
antenna Vs mine.

Well, maybe at this point, but not previously.

The argument has always been about your coax-fed dipole antenna
Vs my G5RV antenna.

Pse take this ****ing contest to private email.

Dev Null wrote:
Pse take this ****ing contest to private email.

What no "ploink!"? In case you missed it, this thread is
about improvements that can be made to the standard G5RV,
something in which tens of thousands of hams might be
interested.
--
73, Cecil, W5DXP



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Cecil Moore wrote:



The argument has always been about your coax-fed dipole antenna
Vs my G5RV antenna.

I'm afraid not Cecil. You are just one of many that seem to run those
things...


You missed the question...How would I know you do that unless you tell
me in advance...I'm not a mind reader...

My antenna is a G5RV. You said your dipole would beat "any" G5RV,
presumably including mine. Your ignorance of my G5RV didn't enter
into the discussion at the time. You didn't even slow down to wonder
if a well-designed G5RV might equal your dipole on 75m.

I think it would *still* probably slightly beat your antenna. I'm fairly
certain even your G5RV will not be a complete equal to my coax fed
dipole. But that is my opinion, and it's not worth 100 more posts to
argue about it. It's common knowledge a coax fed dipole on the low bands
can be in the range of 95% +- efficient as far as the whole system. You
claim to be in that neighborhood, and may well be. But I'd have to see
it to totally believe you would be effectively equal. I bet on the air,
you would still see a slight difference. Might be small, but I bet it
would be there. I still don't like the coax/choke/ladderline combo
despite your claims that they are totally lossless. If you were to run
ladder line the whole way, I'd have much less trouble believing you.


Yes. IF...But I will still prefer the coax fed dipole.

If the design flaws of the G5RV are fixed, we then shift from
performance to preference?

Well, I suppose, but I would still prefer normal dipoles.

Your antenna is different than the vast majority used if what you
say is true.

It's a well-designed G5RV, the best I know of. You said you dipole would
beat "any" G5RV by S-units.

No I didn't . I've clearly agreed with improvements it could be a lot
closer. "As in your's" You reposted it below yourself... But yes, I
will repeat...My dipoles will handily beat *most* G5RV's on 80m.
Probably even yours by a slight amount.


If you have improved yours, I'm glad. You may well have a decent
antenna. But you need to spread the word, because most other's that
are unmodified are still gonna be lame radiators.

I posted my actual measurements yesterday. To optimize a G5RV for 75m,
make the series section transformer 25 feet long and put a 1000 pf
capacitor in parallel at the coax/open-wire junction. The beauty is
that you still have the framework for an all-HF-band antenna. Take
away the cap and extend the series section to 36 feet and you have
a G5RV optimized for 40m and 17m, my favorite bands. It takes about
two minutes for me to make that change but it could be automated.

I guess thats great if you are worried about all bands...I'm more
worried about brute performance on the band I'd be actually using at
field day...We aren't discussing home antennas...I don't think they even
do 17m on FD...

What proposal do you
offer to correct the feedline deficiencies of the average storebought
windom, or OCF dipole on 40 and 80m?

The original windom, powered by a tube transmitter with a pi-net matching
network, was a pretty good antenna. For today's "Windoms", I would advise
everyone to feed OCF's with open-wire line, equipped with an excellent
choke, at a current maximum point, using whatever ratio balun is appropriate.
I had an OCF in college, fed with open-wire line, powered by a Heathkit with
a pi-net tuning network. It's feedpoint impedance on the harmonically related
bands was in the neighborhood of 300 ohms. Matching a tube final to 300 ohms
through a pi-net tuner is pretty much a no-brainer and relatively lossless.

I'll let all those tube rig users at field day in on this information.
But most I see use solid state rigs...But I'll pass this on anyway...
They most all are using the tuners, so only a feedline change will be
needed. I bet they still will have inferior radiating devices in the end
though.....:(
Myself, I think multiband 102 ft dipoles should be fed only with ladder
line...Why are you not using your cut ladder line method for G5RV's?
Enquiring minds wanna know...:/ Why would someone prefer a G5RV over
your normal 80m size all band ladder line fed antenna for FD on 80m?
Enquiring minds wanna know that too...:}
Actually, I could care less what people use at field day, I just wonder
why many I see seem to prefer semi-dummy loads when they have the room
to avoid it...It's gotten to where full size efficient antennas seem to
be the exception, not the norm. And most have never heard of you, or
your modifications, and many are not really into antennas that much,
except to know they have to string them up somewhere. So they just
semi-dummy load along, blissfully unaware it would seem...They don't
know what they miss, because many never try one, thinking they need all
those extra bands...A regular coax fed dipole is not fancy or gimmicky
enough I guess... Oh well..G5RV onwards folks! MK

--
http://web.wt.net/~nm5k

Mark Keith wrote:
I think it would *still* probably slightly beat your antenna. I'm fairly
certain even your G5RV will not be a complete equal to my coax fed
dipole.

But you, yourself, have admitted that the difference is negligible. It
is indeed around 0.4 dB according to all my calculations. And the reward
is that one gets eight antennas for the price of one, i.e. 8 HF band coverage.
If you were feeding your 75m dipole with ladder-line, I wouldn't have nearly
as strong an argument.

Myself, I think multiband 102 ft dipoles should be fed only with ladder
line...Why are you not using your cut ladder line method for G5RV's?
Enquiring minds wanna know...:/

Because it is so easy to achieve nearly a 50+j0 ohm feedpoint impedance at
the series section to coax junction. It is actually relatively difficult
to achieve nearly a 50+j0 ohm impedance using my variable length ladder-
line scheme at the operating position with a 102 foot dipole. But it is
easy with a 130 foot dipole. I simply got tired of the bad rap you and
others were giving G5RVs and chopped my 130 foot dipole to 102 feet. Now
you have to suffer the consequences. :-) What I am trying to demonstrate
is how series matching section transformers work not just at 1/4WL and
1/2WL but at many other lengths.

Why would someone prefer a G5RV over
your normal 80m size all band ladder line fed antenna for FD on 80m?
Enquiring minds wanna know that too...:}

Many hams cannot string a 130 foot dipole but can manage a 102 foot dipole.
I've pushed the 130 foot dipole for years. Now I'm pushing the 102 foot
dipole. Sorry if that is politically incorrect. I simply cannot stand by
and allow new old wives' tales to take over ham radio.
--
73, Cecil, W5DXP



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Cecil Moore wrote in message ...
Brian Kelly wrote:
I've read the whole thread thru Tuesday AM, I get your point . .
. . . see if it's possible to cover that range with some
single specific length of ladderline and the two-section BC variable
cap? If yes I think you have a real keeper idea.

Maybe you'll like this one. 110 ft dipole at 40 ft, fed with 110 ft of
450 ohm ladder-line and tuned with a single control dual-gang variable cap,
i.e. no conventional antenna tuner.

.. . . OK but 110 feet of feedline to an antenna at 40 feet is a whole
lot of feedline to deal with under normal installation condx. At least
around here in suburbia.

Such an antenna system covers the entire
75-80m band with a 50 ohm SWR ranging from 1.7 at 3.5 MHz to 1.0 at 4.0 MHz,
according to EZNEC. Full band coverage at the twist of one knob? You likeie?

Sure do, could be extremely useful, I've moved it into my "idea book".
It's an easily tunable 80/75 variation on the similar antennas in your
website.

For a coax fed dipole, EZNEC reports an SWR=2:1 bandwidth of 170 kHz.

That's roughly what I get with with Nec-Win-Plus. If I make the dipole
131 feet long I get the following SWRs:

3.50 Mhz = 3.2
3.65 Mhz = 1.5 (curve min point)
3.80 Mhz = 3.5
4.00 Mhz = 4.7

So it's not possible to get much bandwidth across 80/75 with a simple
dipole without an ATU no matter how you diddle it. Then you're down to
a low-loss tuning scheme like you've come up with which in this case
is a complete no-brainer. IF one can figure out to what to do with all
the excess feedline without messing it up.

w3rv

Brian Kelly wrote:
. . . OK but 110 feet of feedline to an antenna at 40 feet is a whole
lot of feedline to deal with under normal installation condx. At least
around here in suburbia.

Hey, but not for field day. Whoever heard of a "field" with no room for
110 feet of feedline?

IF one can figure out to what to do with all
the excess feedline without messing it up.

It can be coiled into a big helix as long as the adjacent coils are
a couple of feet apart. You can run an insulated rope to the antenna
feedpoint and coil the ladder-line on the rope with the coils tiewrapped
a couple of feet apart. At the least you would have a conversation piece
to discuss over 807s (the best part of field day. :-) A photo of it would
probably make it into QST since it looks somewhat like a slinky. ;-)
--
73, Cecil, W5DXP



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Cecil Moore wrote:

Mark Keith wrote:
I think it would *still* probably slightly beat your antenna. I'm fairly
certain even your G5RV will not be a complete equal to my coax fed
dipole.

But you, yourself, have admitted that the difference is negligible.

Thats only between mine and yours, and IF your's works as advertised. In
the real world, I have never seen this happen yet. Heck, in theory,
there should be no real difference in using a coax fed 80m dipole, and a
80 dipole fed with my tuner, and ladder line. Using the bare min
inductance of course... In theory, there should not be enough difference
to notice. In theory...So far in the real world, it hasn't worked that
way for me. I saw a noticable difference. Probably about 5 db's worth if
using strong signals in the upper part of an S meters range. Now, in
that case, the loss was quite livable for just average use. It wasn't
near as bad the the G5RV's we used. The feedline loss in THOSE
PARTICULAR G5RV's was quite large on 80m. I actually had quite a bit of
trouble even contacting many other stations. Led to hair loss...

It
is indeed around 0.4 dB according to all my calculations. And the reward
is that one gets eight antennas for the price of one, i.e. 8 HF band coverage.
If you were feeding your 75m dipole with ladder-line, I wouldn't have nearly
as strong an argument.

Myself, I think multiband 102 ft dipoles should be fed only with ladder
line...Why are you not using your cut ladder line method for G5RV's?
Enquiring minds wanna know...:/

Because it is so easy to achieve nearly a 50+j0 ohm feedpoint impedance at
the series section to coax junction. It is actually relatively difficult
to achieve nearly a 50+j0 ohm impedance using my variable length ladder-
line scheme at the operating position with a 102 foot dipole. But it is
easy with a 130 foot dipole. I simply got tired of the bad rap you and
others were giving G5RVs and chopped my 130 foot dipole to 102 feet. Now
you have to suffer the consequences. :-)

How's that? If you change it, it's not quite the usual "g5rv" that I
complain about. It's a different antenna. Actually, I think calling it a
G5RV is silly unless it's used as a 20m monoband antenna as was
originally designed. The G5RV's I saw were really bad on 80m. It's not
just something I'm making up. I was so disgusted with the things after
the 2nd FD, I refused to ever use one again. And I haven't. I bring my
own wire and coax just to make sure I don't get stuck on one. And I
wasn't the only one complaining either...
I won't be suffering with a system efficiency in the mid 90's...

What I am trying to demonstrate
is how series matching section transformers work not just at 1/4WL and
1/2WL but at many other lengths.

Well, thats fine. But I'm trying to tell everyone to live a little! Go
with gusto! You only spin once! Use a full size efficient, resonant,
antenna if you want manly 80m FD results and have the room for it. I
suppose being resonant should not really be an issue, but in this case
it is. It's hard to beat a 50 ohm antenna , fed with 50 ohm line, by a
50 ohm radio. To me, that is the "perfect" setup. It just so happens a
1/2 wave dipole lets all this fall into place. And it just happens that
a 1/2 wave dipole has a near optimum pattern for the usual FD type
operation on 80m. To me, anything else is like sticking a finger on the
perfect painting , and smearing it around before it's dry.. :/
I guess this is what led me to question your choice of the perfect FD
antenna. 80m, being the band of real issue.


Why would someone prefer a G5RV over
your normal 80m size all band ladder line fed antenna for FD on 80m?
Enquiring minds wanna know that too...:}

Many hams cannot string a 130 foot dipole but can manage a 102 foot dipole.

At field day? A lousy 15 more ft a side? Man, they need to find a better
place for field day...
Thats sad....:(
Here's where we were last
year...http://bvarc.freeshell.org/images/FD2003/index.html
No trouble stringing up a real dipole around that place..."It's a fire
training facility in Richmond Tx."
Note my portable tower and beam I bring on a motorcycle trailer. Thats
why I fear you not on the upper bands....:) BTW...My tower was the
lowest, but the highest scoring...Due mainly to superior operating
skills though...No, not by me...:/ I didn't use it...Blame N5XZ...
There are other beams also... If I were to FD by myself, I'd drive down
to the beach and operate off the salt water.
Probably could just sit in the truck and use the mobile setup...
Wouldn't need to get out and do any actual work... :/

I've pushed the 130 foot dipole for years. Now I'm pushing the 102 foot
dipole. Sorry if that is politically incorrect. I simply cannot stand by
and allow new old wives' tales to take over ham radio.

I like your all ladder line design better from an efficiency
standpoint...But claiming a coax fed dipole is nearly invincable as far
as wire ant/dipole efficiency's go, is hardly a wives tail. MK
--
http://web.wt.net/~nm5k

Cecil Moore wrote in message ...

Brian Kelly wrote:
. . . OK but 110 feet of feedline to an antenna at 40 feet is a whole
lot of feedline to deal with under normal installation condx. At least
around here in suburbia.

Hey, but not for field day. Whoever heard of a "field" with no room for
110 feet of feedline?

Well . . it sorta "depends". In the instant case the FD "field" is one
of my daughters' 1/4 acre back yard, three decent-size hardwoods
spread out in maybe a 120 foot straight line and that's it. The other
op will probably be N2EY and he isn't into deep bush ops either.

IF one can figure out to what to do with all
the excess feedline without messing it up.

It can be coiled into a big helix as long as the adjacent coils are
a couple of feet apart. You can run an insulated rope to the antenna
feedpoint and coil the ladder-line on the rope with the coils tiewrapped
a couple of feet apart.

That's slick.

At the least you would have a conversation piece
to discuss over 807s (the best part of field day. :-) A photo of it would
probably make it into QST since it looks somewhat like a slinky. ;-)

I was thinking more along the lines of sniping one of the orange
barrels which are the Pennsylvania State Flower. They're quite readily
available at construction sites along the PA Turnpike and
slinky-wrapping feedline around one of those should do the job.

Let's see here, 2.5 feet diameter times Pi . . 7.85398 feet per wrap .
.. yeah, that would get rid of most of the ladderline. At worst maybe
I'd need a couple of 'em in series.

QRX for the QST cover shot.

w3rv

Mark Keith wrote:
I was so disgusted with the things after
the 2nd FD, I refused to ever use one again. And I haven't. I bring my
own wire and coax just to make sure I don't get stuck on one. And I
wasn't the only one complaining either...
I won't be suffering with a system efficiency in the mid 90's...

It would be easy to try my G5RV modification. For 3.8 MHz, it is
25 ft of "450" ladder-line with a 1000 pf cap in parallel at the
ladder-line/coax junction. I wish you would open your closed mind
and try it sometime.

I guess this is what led me to question your choice of the perfect FD
antenna. 80m, being the band of real issue.

A perfect FD antenna would allow one to change bands relatively
quickly without sacrificing performance. My G5RV does that.

The 110 ft dipole that I came up with has an SWR of less than 1.7:1
over the entire 75-80m band. That sure beats the bandwidth of a
resonant coax-fed dipole.

W5DXP wrote:
Many hams cannot string a 130 foot dipole but can manage a 102 foot dipole.

At field day?

No, at their QTH. Many hams have reported that they just don't have
130 feet of room.

I simply cannot stand by
and allow new old wives' tales to take over ham radio.

I like your all ladder line design better from an efficiency
standpoint...But claiming a coax fed dipole is nearly invincable as far
as wire ant/dipole efficiency's go, is hardly a wives tail. MK

That's not the old wives' tale. The old wives' tale is, "A G5RV
is a terrible antenna that cannot be improved to near perfection."
With minor modifications, a G5RV will compete favorably with any
other HF dipole on any HF band.
--
73, Cecil, W5DXP



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Cecil Moore wrote in message ...
Brian Kelly wrote:
. . . OK but 110 feet of feedline to an antenna at 40 feet is a whole
lot of feedline to deal with under normal installation condx. At least
around here in suburbia.
.. . . .

Cecil check me here if you will. I brought up a CAD program to sketch
your 80/75 dipole and ran into a puzzler as soon as I started to draw
it. Center fed 110' flattop, 110' balanced feedline. No problem. The
question arose when I tried to lay in the tuning caps. My
understanding is that the "input" sides of the two caps are connected
to each of the two wires at the "output" end of the feedline. Then the
"output" side of one cap goes to the shield of the coax and the output
side of the other cap goes to the center conductor of the coax. This
is not possible with a typical double-section variable BC-type cap
because one side of such caps is a common ("ground"). A pair of caps
mechanically coupled via an insulated shaft coupling but completely
isolated electrically from each other should work. Where's the
glitch??

w3rv

Brian Kelly wrote:
A pair of caps
mechanically coupled via an insulated shaft coupling but completely
isolated electrically from each other should work.

Yes, that's what I had in mind. Mine are side-by-side with a
non-conducting fiber-chain connecting the shafts. Same with my
two rotary coils. When I said "dual-ganged", I meant mechanically
ganged, not electrically ganged.

| |/
Coax center wire--------|/|--------feedline--------
/| |
ganged variable caps to dipole
| |/
Coax braid--------------|/|--------feedline--------
/| |

And of course, there needs to be a choke between the coax and
the caps.
--
73, Cecil, W5DXP

N2EY wrote:
Biggest headache, though, is switching the various lengths for
different bands.

No switching the various lengths on this one, Jim. Just a 110 ft
dipole fed with about 110 ft of fixed length ladder-line with two
series variable caps as the one knob tuner. Covers from 3.5 MHz to
4.0 MHz with an SWR less than 1.7:1 and no lossy coils needed.
--
73, Cecil, W5DXP

Cecil Moore wrote:

N2EY wrote:

Biggest headache, though, is switching the various lengths for
different bands.

No switching the various lengths on this one, Jim. Just a 110 ft
dipole fed with about 110 ft of fixed length ladder-line with two
series variable caps as the one knob tuner. Covers from 3.5 MHz to
4.0 MHz with an SWR less than 1.7:1 and no lossy coils needed.

I apologize to everyone for a mental blunder I made with this
proposed antenna. The reactances are capacitive, not inductive.
It would have to be tuned with series inductors which defeats
the propose of a low loss design.
--
73, Cecil, W5DXP

Covers from 3.5 MHz to
4.0 MHz with an SWR less than 1.7:1 and no lossy coils needed.
--
73, Cecil, W5DXP

========================

Lossy coils replaced by lossier transmission lines ? ;o)
---
Reg. G4FGQ

Reg Edwards wrote:

Covers from 3.5 MHz to
4.0 MHz with an SWR less than 1.7:1 and no lossy coils needed.

Lossy coils replaced by lossier transmission lines ? ;o)

The loss in 100 ft. of open-wire line on 4 MHz is so low
it isn't even on the chart. :-)
--
73, Cecil, W5DXP

The loss in 100 ft. of open-wire line on 4 MHz is so low
it isn't even on the chart. :-)
--
73, Cecil, W5DXP

=========================

The loss at 30 MHz with a very high SWR is on MY chart.

And the loss in properly used coils is very small.

But either way, the difference between the two methods is so small you are
unfairly claiming an advantage in the use of transmission lines. Do some
accurate calculations to see what actually happens.
----
Reg.

I apologize to everyone
The reactances are capacitive, not inductive.

Cecil, Looks to me like a 108' flattop, 40' up, fed with 44' of 450 ohm line
might get less than 2:1 across 80 meters with 250pf variable caps. The magic
numbers are 3.8 mhz and 132pf for 1:1. No lossy coils.
I have some silver plated roller inductors that I use in a re-configurable
"L" network that I'll bet used with the above antenna will produce efficiencies
near what the vari-caps will, and 1:1 across 80M. I really don't think the
silver plating has that much to do with it.:-) Anyway that is what I have used
on Field Day.


73 Gary N4AST

Reg Edwards wrote:
But either way, the difference between the two methods is so small you are
unfairly claiming an advantage in the use of transmission lines. Do some
accurate calculations to see what actually happens.

Exactly how can coils replace the transmission line it takes to get
the signal from the hamshack to the antenna? I would love to eliminate
my transmission line but I don't know how.
--
73, Cecil, W5DXP



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JGBOYLES wrote:
Cecil, Looks to me like a 108' flattop, 40' up, fed with 44' of 450 ohm line
might get less than 2:1 across 80 meters with 250pf variable caps. The magic
numbers are 3.8 mhz and 132pf for 1:1. No lossy coils.

Thanks Gary, with a little modeling and experimentation, almost any
reasonable antenna problem can be solved. It's not enough to say,
"A G5RV is a terrible antenna". The question that should be asked is,
"Exactly what is wrong with a G5RV and how can it be fixed?"
--
73, Cecil, W5DXP



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Although your method works well you unfairly attribute it to the G5RV. This
undeservedly attaches prestige to that over-rated antenna.

Immediately you change the length of the feedline from 1/2-wavelength at
14.15 MHz it is no longer a G5RV.

And in addition to a top length of 102 feet there is an enormous number of
other top lengths which will work in the manner you describe. 102 feet is
no more magical than 118.5 radials.

Do you hold shares in a G5RV manufacturer? ;o)
----
Reg, G4FGQ

Reg Edwards wrote:
Immediately you change the length of the feedline from 1/2-wavelength at
14.15 MHz it is no longer a G5RV.

Yes, Great Pharaoh, so let it be written, so let it be done. :-)
--
73, Cecil, W5DXP



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It's not enough to say,
"A G5RV is a terrible antenna".
A G5RV is a terrible antenna if it did not do well the last time you used
it. HF antennas and propagation being what they are, it is difficult to label
any antenna as terrible.
A G5RV type antenna in its many configurations ought to work as advertised.
And as you have proved Cecil, it can be tweaked.

73 Gary N4AST