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What do the following things have in common: my multi-band dipole, my
dummy load, a toaster element, and a 100W lightbulb?

Answer: I can connect all three to my antenna tuner, get a reasonable
SWR match, and transmit into them.

Now which one makes for the more efficient radiator[1]?

Answer: I have no idea.[2]

What's the best way to find out for what bands (if any) my current
antenna is best suited? Would something like the Antenna Analyzer II
(http://www.amqrp.org/kits/antanal/) or the 'Tenna Dipper
(http://4sqrp.com/kits/kits.htm) answer this question?

Those two devices only seem to be good at answering the following
question: "At what frequency does this antenna/feedline have the
lowest SWR?". I don't think that this question is the same question
that I asked -- in other words, I am not convinced that the
antenna/feedline with the lowest SWR is necessarily the most efficient
radiator, especially when an antenna tuner is involved.

To those who say "the one that gets you more QSOs is the best", I'd
like to say that since the weekend I set up the antenna (the weekend
of the last California QSO Party) I've had *one* QSO, and now that
person (several towns away) can't clearly hear me when I transmit with
100W on any of the four HF bands I've tried.

Does anyone have any real answers (or at least good suggestions to
collect more information) for me?

Jack.
(a little frustrated, yeah)

[1] I define the most efficient radiator as the one which pushes out
the most signal for a given power level on a given frequency. If
this definition is in error, helping me correct this could render
the entire point moot.

[2] Well, I'm almost positive the order is: dipole, lightbulb,
toaster element, dummy load. Almost. I'm not sure where the
dipole fits in, to be honest.
- --
Jack Twilley
jmt at twilley dot org
http colon slash slash www dot twilley dot org slash tilde jmt slash
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On Thu, 11 Mar 2004 20:23:13 -0800, Jack Twilley
wrote:
What's the best way to find out for what bands (if any) my current
antenna is best suited? Would something like the Antenna Analyzer II
(http://www.amqrp.org/kits/antanal/) or the 'Tenna Dipper
(http://4sqrp.com/kits/kits.htm) answer this question?

These are toys when it comes to the grist of your question. No
analyzer will answer what is best as that is a subjective issue.
Further, an antenna has more characteristics than feed point Z which
impact the nature of your enquiry far more.

A low antenna that warms the ground will look like a charmer to the
analyzer, but then so would your dummy load. Get the idea? You
already anticipate this I am sure.

The old methods, prior to the invention of analyzers, encompassed a
simple sanity/reality check with the field strength meter. Put one
100 wavelengths out and take a reading. Do the same with a buddy in
town. The differences should be telling. This will reveal how much
power has escaped the grip of loss.

Repeat with a DX contact (you and your buddy working the same remote
station). You already have a basis of comparison for line of sight
power levels, you can now determine how well your elevation angles
work out. If you buddy comes in #1 and has a higher antenna, you got
a clue where your next step should be. But higher, lower, whatever,
differences will be revealing. No differences? Well then perhaps
doing some Dale Carnegie courses are in order.

73's
Richard Clark, KB7QHC

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"Richard" == Richard Clark writes:

Jack What's the best way to find out for what bands (if any) my
Jack current antenna is best suited? Would something like the
Jack Antenna Analyzer II (http://www.amqrp.org/kits/antanal/) or the
Jack 'Tenna Dipper (http://4sqrp.com/kits/kits.htm) answer this
Jack question?

Richard These are toys when it comes to the grist of your question.
Richard No analyzer will answer what is best as that is a subjective
Richard issue. Further, an antenna has more characteristics than
Richard feed point Z which impact the nature of your enquiry far
Richard more.

That's pretty much what I figured. I tried to provide a definition
for best that was more objective than subjective.

Richard A low antenna that warms the ground will look like a charmer
Richard to the analyzer, but then so would your dummy load. Get the
Richard idea? You already anticipate this I am sure.

Exactly. This is the same antenna that I've mentioned in the past,
less than twenty feet off the ground and less than five feet from the
house (which towers over the antenna by ten feet at its highest
point).

Richard The old methods, prior to the invention of analyzers,
Richard encompassed a simple sanity/reality check with the field
Richard strength meter. Put one 100 wavelengths out and take a
Richard reading. Do the same with a buddy in town. The differences
Richard should be telling. This will reveal how much power has
Richard escaped the grip of loss.

While I don't have a field strength meter, I do have a friend with a
DC-to-daylight receiver. He was able to receive me loud and clear
over a mile away. One hundred wavelengths would be twenty-four miles
- -- if he had a real antenna, he'd be perfectly situated for that kind
of test, but all he has is the whip that came with the receiver, so
I'm not sure that's going to be a valid test.

Richard Repeat with a DX contact (you and your buddy working the same
Richard remote station).

[... rest elided ...]

Ahahahaha. Richard, I've worked a DX contact *once*. That was day
one of the antenna's life, during the California QSO Party, when I
logged a contact with a guy in Germany. I have trouble working people
several towns over, and in fact have had only one QSO since the
weekend the antenna was installed. This part of the test is a little
optimistic.

Richard 73's Richard Clark, KB7QHC

Thanks!

Jack.
- --
Jack Twilley
jmt at twilley dot org
http colon slash slash www dot twilley dot org slash tilde jmt slash
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On Fri, 12 Mar 2004 00:30:57 -0800, Jack Twilley
wrote:
While I don't have a field strength meter, I do have a friend with a
DC-to-daylight receiver. He was able to receive me loud and clear
over a mile away. One hundred wavelengths would be twenty-four miles
- -- if he had a real antenna, he'd be perfectly situated for that kind
of test, but all he has is the whip that came with the receiver, so
I'm not sure that's going to be a valid test.

Hi Jack,

You need a rig with a good, calibrated readout. I should use the word
"calibrated" with care. Actually it needs resolution and stability so
that it can make comparisons. Using a step attenuator and its reading
to achieve the same indication is the best method.

You still need someone else to compare against. Coming in loud and
clear might easily (or poorly) be accomplished driving a leaky dummy
load. A friend of mine once QSO'd her girl friend in AK all while on
her dummy load (20M).

73's
Richard Clark, KB7QHC

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"Richard" == Richard Clark writes:

[...]

Richard Hi Jack,

Richard You need a rig with a good, calibrated readout. I should use
Richard the word "calibrated" with care. Actually it needs
Richard resolution and stability so that it can make comparisons.
Richard Using a step attenuator and its reading to achieve the same
Richard indication is the best method.

None of those things are finding themselves in my junk box at the
moment. In fact, I strongly suspect my HF rig needs to be calibrated
and tuned, and I'm slowly gathering the tools required to do that.
Until then, I've got to work with what I have.

Richard You still need someone else to compare against. Coming in
Richard loud and clear might easily (or poorly) be accomplished
Richard driving a leaky dummy load. A friend of mine once QSO'd her
Richard girl friend in AK all while on her dummy load (20M).

Alas, the sunspots are no longer with us, it seems.

Richard 73's Richard Clark, KB7QHC

Jack.
- --
Jack Twilley
jmt at twilley dot org
http colon slash slash www dot twilley dot org slash tilde jmt slash
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Jack,

Have you determined that the radio is actually putting out 100W? The light
bulb test should give some indication. When I first got licensed on HF I
went through a bunch of antennas at less than 20 feet with essentially 0
results. For starters, unless you are DX, nobody will talk to you on 75 or
20 m SSB unless you are 5-9. I made my first contact half way across the
country on 15 m by using a 3 el 6 meter beam at 12 feet (In the attic of a 1
story house). Try getting out during a contest, but you really want to get
the wire at least 30 feet up. I don't think you mentioned what the antenna
is, or what bands you have tried.

Tam/WB2TT
"Jack Twilley" wrote in message
...
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"Richard" == Richard Clark writes:

Jack What's the best way to find out for what bands (if any) my
Jack current antenna is best suited? Would something like the
Jack Antenna Analyzer II (http://www.amqrp.org/kits/antanal/) or the
Jack 'Tenna Dipper (http://4sqrp.com/kits/kits.htm) answer this
Jack question?

Richard These are toys when it comes to the grist of your question.
Richard No analyzer will answer what is best as that is a subjective
Richard issue. Further, an antenna has more characteristics than
Richard feed point Z which impact the nature of your enquiry far
Richard more.

That's pretty much what I figured. I tried to provide a definition
for best that was more objective than subjective.

Richard A low antenna that warms the ground will look like a charmer
Richard to the analyzer, but then so would your dummy load. Get the
Richard idea? You already anticipate this I am sure.

Exactly. This is the same antenna that I've mentioned in the past,
less than twenty feet off the ground and less than five feet from the
house (which towers over the antenna by ten feet at its highest
point).

Richard The old methods, prior to the invention of analyzers,
Richard encompassed a simple sanity/reality check with the field
Richard strength meter. Put one 100 wavelengths out and take a
Richard reading. Do the same with a buddy in town. The differences
Richard should be telling. This will reveal how much power has
Richard escaped the grip of loss.

While I don't have a field strength meter, I do have a friend with a
DC-to-daylight receiver. He was able to receive me loud and clear
over a mile away. One hundred wavelengths would be twenty-four miles
- -- if he had a real antenna, he'd be perfectly situated for that kind
of test, but all he has is the whip that came with the receiver, so
I'm not sure that's going to be a valid test.

Richard Repeat with a DX contact (you and your buddy working the same
Richard remote station).

[... rest elided ...]

Ahahahaha. Richard, I've worked a DX contact *once*. That was day
one of the antenna's life, during the California QSO Party, when I
logged a contact with a guy in Germany. I have trouble working people
several towns over, and in fact have had only one QSO since the
weekend the antenna was installed. This part of the test is a little
optimistic.

Richard 73's Richard Clark, KB7QHC

Thanks!

Jack.
- --
Jack Twilley
jmt at twilley dot org
http colon slash slash www dot twilley dot org slash tilde jmt slash
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"Tam" == t-tammaru Tam writes:

Tam Jack, Have you determined that the radio is actually putting out
Tam 100W? The light bulb test should give some indication.

I have an MFJ Versa Tuner II which has a power meter. It's not
laboratory certified, but the needle does go all the way up to 100
when I tune up and transmit.

Tam When I first got licensed on HF I went through a bunch of
Tam antennas at less than 20 feet with essentially 0 results. For
Tam starters, unless you are DX, nobody will talk to you on 75 or 20m
Tam SSB unless you are 5-9.

This disappoints me, and I really hope it's not true.

Tam I made my first contact half way across the country on 15 m by
Tam using a 3 el 6 meter beam at 12 feet (In the attic of a 1 story
Tam house). Try getting out during a contest, but you really want to
Tam get the wire at least 30 feet up. I don't think you mentioned
Tam what the antenna is, or what bands you have tried.

I can't get the wire any higher than it is right now at this current
location. This is pretty much the best I can do, and this little
antenna already totally fills my yard and the yards of each of my
neighbors (with their permission). It's a multiband fan dipole with
three pairs of legs, cut for 40, 20, and 10.

My current goal is to acquire a noise bridge and see where the antenna
resonates, then trim the antenna as necessary until it resonates in
the right places. After that, I'll look into feedline length
modifications as necessary. Hopefully those two approaches will
resolve my current issue.

Jack.
- --
Jack Twilley
jmt at twilley dot org
http colon slash slash www dot twilley dot org slash tilde jmt slash
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Jack,

Just some comments. I think you have the right kind of antenna with the fan
dipoles. You say it is lower than the house; can't you prop up at least some
of it to the height of the house, or a couple of feet more. Have you
determined that the radio puts out the same power on SSB (whistle) as when
you tune up (on CW?) ?

I made most of my early contacts during contests, by answereing calls from
people who did not have big pileups. If they hear you, they will come back
to you. I did get my SSB DXCC with a Junior beam at 28 feet.

To trim a multiple dipole like yours, you have to trim the lowest frequency
first, and work your way up. I have a 40/17/12 antenna like that, and this
is the only way I got it to convege in EZNEC.

Tam/WB2TT
"Jack Twilley" wrote in message
...
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"Tam" == t-tammaru Tam writes:

Tam Jack, Have you determined that the radio is actually putting out
Tam 100W? The light bulb test should give some indication.

I have an MFJ Versa Tuner II which has a power meter. It's not
laboratory certified, but the needle does go all the way up to 100
when I tune up and transmit.

Tam When I first got licensed on HF I went through a bunch of
Tam antennas at less than 20 feet with essentially 0 results. For
Tam starters, unless you are DX, nobody will talk to you on 75 or 20m
Tam SSB unless you are 5-9.

This disappoints me, and I really hope it's not true.

Tam I made my first contact half way across the country on 15 m by
Tam using a 3 el 6 meter beam at 12 feet (In the attic of a 1 story
Tam house). Try getting out during a contest, but you really want to
Tam get the wire at least 30 feet up. I don't think you mentioned
Tam what the antenna is, or what bands you have tried.

I can't get the wire any higher than it is right now at this current
location. This is pretty much the best I can do, and this little
antenna already totally fills my yard and the yards of each of my
neighbors (with their permission). It's a multiband fan dipole with
three pairs of legs, cut for 40, 20, and 10.

My current goal is to acquire a noise bridge and see where the antenna
resonates, then trim the antenna as necessary until it resonates in
the right places. After that, I'll look into feedline length
modifications as necessary. Hopefully those two approaches will
resolve my current issue.

Jack.
- --
Jack Twilley
jmt at twilley dot org
http colon slash slash www dot twilley dot org slash tilde jmt slash
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Jack Twilley wrote in message ...
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"Tam" == t-tammaru Tam writes:

Tam Jack, Have you determined that the radio is actually putting out
Tam 100W? The light bulb test should give some indication.

I have an MFJ Versa Tuner II which has a power meter. It's not
laboratory certified, but the needle does go all the way up to 100
when I tune up and transmit.

Well, you know the radio works...



I can't get the wire any higher than it is right now at this current
location. This is pretty much the best I can do, and this little
antenna already totally fills my yard and the yards of each of my
neighbors (with their permission). It's a multiband fan dipole with
three pairs of legs, cut for 40, 20, and 10.

Your antenna is *very* efficient on those three bands, unless you have
coax or connection problems and power is not making it to the antenna.
BTW, the 40 legs will work 15 ok, if you tweak the match with the
tuner...Will be pretty efficient on 15 also as a 1.5 wl dipole.

My current goal is to acquire a noise bridge and see where the antenna
resonates, then trim the antenna as necessary until it resonates in
the right places.

Good idea. You shouldn't really need the tuner.

After that, I'll look into feedline length
modifications as necessary.

Should be unneeded. If coax length radically varies SWR, you need a
1:1 balun or choke to cut radation from the shield.

Hopefully those two approaches will
resolve my current issue.

Actually, I don't think you have a problem, assuming no coax or
connector problems. Does the receive noise level, and signal levels
sound fairly normal, or dead? I think the main problem is trying to
work locally using ground wave, with an antenna that is poorly suited
for that. But, you should usually be able to work 40m in the day,
being it's mainly NVIS. 20 miles is a long way for a low horizontal
dipole to work locally without the help of skywave. A purely
horizontal antenna has no groundwave, if no vertical feedline
radiation, etc. It has a space wave, but it's going to be hard to work
20 miles over the noise. If both of you had verticals, it would
probably be easy. As far as comparing antennas, all you have to do is
use a antenna switch, and see which is best on receive. Operation is
reciprical 98.8 % of the time, so a transmit test is unneeded. You
should be having no problems working 40m in the day, or even 20m to
stateside stuff. 10m local will be very tough, but you should be able
to work some skywave. A vertical is much better for 10m local. 20 ft
high is high enough to work for medium distance skywave. Maybe not a
barnburner, but it should be working for general gov work...I've run
many lower than that when camping, and had no problems. If you can't
hardly work *anyone*, I would check your connections, and coax , etc.
Also, if you use the tuner for now, use the bare minimum inductance to
get a usable match. That will help reduce tuner losses, which can
climb to 20% or so if too much coil is used.
I would eventually tune the antenna up, and dump the tuner. There is
no real need for it, unless you go off far from where you normally
have it tuned. IE: work some CW when the antenna is tuned for the fone
band. MK

Jack Twilley wrote in message

BTW, if you have the legs in the same direction, and close together,
coupling can be a problem. As one mentioned, always start with the
lowest band first, and go up band by band. If you have a coupling
problem, it will almost always be one of the higher band legs being
effected by a lower band leg. You can usually get a usable match if
you vary the wire length. Try to get each band under 2:1 SWR. I run
multi leg dipoles here, but I run mine in different directions and
have few coupling problems. IE: if I had a 40 dipole braodside E/W,
I'd run the 20 dipole N/S. Sometimes if you do have a coupling
problem, just moving the higher band leg a few feet can cure the
problem. You will almost never see a higher band leg effect a lower
band to any great degree. MK