Survey Comments
Unfortunately
First off, I agree with N3ZKP title of "No Such Animal". AB0SI is one of those "Politically Correct" individuals. If these were to start being called Knotheads, he'd probably agree it was the proper term. What these were called, before the days of the auto tuner, was a transmatch. You were trying to match the transmitter's 50 ohm load to the antenna.
In days gone by, you were happy with the bandwidth you could get with the antenna you made, but then again, in those days the radios used tubes, and tubes are much more forgiving than solid state is. A benefit, in those days, it kept the room toasty with the heat it generated. As we progressed into solid state, we as operators, got more greedy with our frequencies and wanted it all. Sadly, I am one, as well. I use the Yaesu FC-757AT, for 160-10 meters, and the MFJ 969 for 6 meters.
Posted by
W2SNJ on 2005-09-04
Some use two!
I use an external and the internal in a FT100MP Mark -V Field, to match a random LW.
The survey should have an option for those who use two.
Posted by
G3OZN on 2005-04-22
Tuners
As most hams know, you can NOT tune an antenna that is NOT resonate with a tuner located in your shack, hooked to un-balanced coax line. You are only tricking your radio into seeing a 50ohm load so the crowbar circuit in your radio allows full output. However nothing in life is free and there are major losses in the tuner, and depending on the amount of mis-match, the loss in the tuner could be greater than 60%!! Now feeding this tuner with balanced line, such as 450ohm ladder line, you are somewhat tuning your antenna, as the balanced line becomes part of the antenna, however you still have the loss in the tuner.
I have on antenna that uses an SGC auto tuner. This tuner is mounted @ the antenna, so it actually becomes part of the antenna and matches it to a 50ohm load. This type of tuner actually tunes the antenna, but again you have inherent losses in this tuner as well. Because we as hams use so many different frequencies, and bands a tuner is a good band-aid for the problem, but not a cure! Nothing beats an antenna that is resonate on your operating frequency! This is what makes the STEPIR work so well, it is actually physcially tuned to resonance for each operating frequency. Never have used one, don't work for the company, but it should be a great performer!! (just out of my operating budget, and would never get it past the CC&R Police!)
73 de W4LGH - Alan
http://www.w4lgh.com
Posted by
W4LGH on 2005-04-14
kk7wn
How about a new question a little more often? Say, about after two weeks.
Posted by
KK7WN on 2005-04-13
Steppir
I use a SteppIR 20m - 6m antenna.great match
on any freq.
and an Acom 2000A which has an internal match
VK3TXZ
Posted by
VK3TXZ on 2005-04-11
Antenna Tuner
Why use an antenna tuner? I work on the opposite principal of making my antennas resonant on the part of the band I most use, then and only then if need to operate when the swr rises do I use a antenna tuner, but I am lucky in having the space for large antennas.
I can quite understand some hams using a tuner, when the lack of space prevents the instalation of full size antennas, but as all extra items in the feeder to the antennas impose losses, we should really be asking ourselves is it necessary? or should I alter the antenna to improve its matching!
Thats my two penny worth.
Roger G4OCO
Posted by
G4OCO on 2005-04-10
I have several antennas that are fed with runs of open wire that are over 300 feet long. I use the AG6K double roller design and it works perfectly at power levels up to the legal limit. The tuner doesn't tune the antenna but matches the transmitter to the line which is connected to a high impedance load.
Posted by
K1WPO on 2005-04-10
Antenna Tuners
Sure I have one built in the rig that keeps it happy and an external one I use to load my 40meter full wave loop which I feed with ladder line I can use it with good results on all bands.73 Joe K0KES
Posted by
K0KES on 2005-04-10
Both
I use the internal one in my IC-765 from time to time, but the MFJ-941 has never failed!
Posted by
KC0KBH on 2005-04-09
It just looks cool
I think it just looks cool sitting with all my radio equipment! Oh yeah, it makes my radio happy too.
Posted by
K4TPC on 2005-04-06
Antenna Tuner
I don't have an HF rig yet, so I will prbably homebrew a
tuner. At the last hamfest I picked up some parts and
pices to build one. I'll see about getting an HF next year
(mabey even the new IC-7000) LOL if it exists!
Posted by
INCOGNITO on 2005-04-06
Antenna Tuner
I don't have an HF rig yet, so I will prbably homebrew a
tuner. At the last hamfest I picked up some parts and
pices to build one. I'll see about getting an HF next year
(mabey even the new IC-7000) LOL if it exists!
Posted by
INCOGNITO on 2005-04-06
Loop
I run a B-I-G loop fed with ladder-line. And, I'm not one for using baluns...so the antenna tuner is a necessity.
Posted by
KB2HSH on 2005-04-03
Loop
I run a B-I-G loop fed with ladder-line. And, I'm not one for using baluns...so the antenna tuner is a necessity.
Posted by
KB2HSH on 2005-04-03
units! units! units!
Guys,
The first thing we teach in undergraduate introduction to physics, and that we stress every day thereafter, is that UNITS matter. It is easy to show the mass/energy equivalence (technicaly, rest mass) because the relationship is constant. Know the mass, know the energy.
However, the power/resistance relationship isn't constant, because resistance isn't the only variable quantity involved in obtaining power. In e=mC^2, C is a constant, and, relativisticaly, the conversion is no different than converting between pounds and grams. On the other hand, p=rI^2 involves two variables. That's how I can get 10w or 100w out of the same antenna.
If you were going to strain the analogy, it would be current that was equivalent to power, not resistance, since, as you've defined it, resistance is what is constant in a given antenna design, not current.
Of course, 'e=mC^2' and 'p=rI^2' are just oversimplifications, and neither applies very well in the quantum world of radiation theory. In the real world, not even mass is constant, as it depends on velocity.
(yes, i do use antenna tuners. external on the 706, internal on the 756.)
Posted by
AE6IP on 2005-04-01
Two points:
1) physicists measure mass in units other than grams all the time. in particle physics, especially high energy physics, it is more convienent to work with electron-volts than with grams.
2) 'radiation resistance' is no less 'real' than any of the rest of field theory. It's not constant, depending on both the geometry of the radiator and the wavelength of the signal, in a relationship that involves the permeability of free space, a well known constant with a value of approximately 1.2e-6 Webers / amp-meter
Posted by
AE6IP on 2005-04-01
Antenna tuners
I thought this was about the use of antenna tuners.
Posted by
KK9H on 2005-03-30
N7PEH
Your explanation makes sense, and I stand corrected insofar as the real part of the antenna impedance includes losses as well as radiation resistance.
My trouble was with the way you phrased your reply to WA6BFH, stating that that radiation resistance "is the measure of power lost in an antenna in radiation .... "
73,
Chuck NI0C
Posted by
NI0C on 2005-03-29
Radiated Power
NI0C ---
I have never been known for writing clearly the first time.
However, I do want to emphasize that radiation resistance
is indeed a measure of "power". The trick here is that the
notion of resistance is used to model this radiated power
in a form that is useful. It is easy for example to compute
the so-called efficiency of an antenna by the ratio of the
"radiation resistance" divided by "total resistance". By
total resistance I mean the real part of the complex
Impedance plus the radiation resistance.
Also, the concept of resistance is useful because an
antenna loses energy (power) in two ways: by radiation
and by ohmic heating. The ohmic heating is not just due
to current losses in a wire though. It is also due to lost
energy by causing currents in other conductors that do
not necessarily radiate (e.g. transmission line or other
nearby conductors). And, it is losses due to hysteresis of
the magnetic field in various media such as air, ground,
trees, conductors, and so on. Of course, these losses may
be small (hopefully most of the time).
And, radiation resistance is a useful concept because
mathematically you can develop a nifty formula for various
kinds of antennas to represent radiation resistance. Of
course, this is almost always an approximation (unless the
antenna were trivial and the mathematical formulation was
analytical). I have done this calculation for various simple
antenna formulations using the vector potential (since it is
current based) but you can skip the Calculus and usually
find these formula in various antenna design reference
texts.
Posted by
K7PEH on 2005-03-29
Radiation resistance
At the risk of belaboring this, I must disagree with your statement that " that radiation resistance
is indeed a measure of "power"." Although you may use power measurements to help derive a resistance number (whether it be a loss resistance or a radiation resistance), resistance is still resistance, and it is measured in ohms, not watts. Power represents a rate of energy into or out of a device, and it is measured in Joules per second, or watts.
Posted by
NI0C on 2005-03-29
laboring the point
NI0C,
OK, I know what you are saying about resistance. But, I
think you are not thinking like a physicist where it is
common to measure things in equivalent units. For
example, a high-energy physicist measures mass using
electron-volts which is a measure of energy. The
connection between the two units is Einstein's famous E
equals M C-squared equation.
In this case, it is indeed power that is being measured.
Although, there is a connecting equation which is from
Ohms law and it states that Power is equal to I-squared
times R. So, we have power and we have a model for
current so what is this thing called resistance in this case.
It is a made up thing -- it does not exist but it is useful in
doing other types of computations with antenna systems.
You will find this through out the antenna theory text
books or the IEEE Antennas & Propagation papers.
So, we have power. The current in this connection is the
current that drives the radiation field and this is the
current density that you find under the integral in the
vector field A formulation. I am assuming a degree of
experience with Maxwell's Equations and unfortunately
the type system here on this editor prevents me from
writing this stuff out.
So, yes, ohms measures resistance and watts measure
power but the physical phenomina in the case of radiated
power is indeed power and the resistance here is nothing
other than a mathematical fabrication and used indirectly
with a connecting formula.
So, I know, I have indeed belabored the point but I think it
is an important point. Radiation resistance is not really a
measure of resistance of a resistor -- the resistor does
not exist. This is not the same thing as the impedance of
an antenna though they are mathematically connected as
well.
Posted by
K7PEH on 2005-03-29
Once more
Nobody said radiation resistance was a resistor. I maintain that if you are to measure resistance (even a hypothetical quantity, and even if you use power measurements to derive the number), you call the result that you get "resistance," not power.
No physicist I know (I'm an engineering educator) measures mass by whatever means, and calls the result something other than mass. That would be just plain wrong.
You don't need to invoke Maxwell's equations or calculus of any kind to understand the simple point I've been making.
Posted by
NI0C on 2005-03-29
OK
NI0C ---
I will give up. But, a physicist does measure mass in
terms of energy. This is done all the time. In fact, In
high-energy theoretical physics, both C (speed of light)
and h (Planck's constant) are set to 1 and this alters the
units of all other physical quantities and there is
absolutely no distinction between energy and mass at that
point. But, a kilogram is still not equal to a joule even
though we say that mass and energy are equivalent.
Likewise, an ohm is not the same as a watt even though
we can say that we are measuring the same physical
quantity using either of these. Albeit, the connection
formula assumed.
So, I think we will have to go about begging to differ on
this notion. And, I think we have bored the other readers
so it is time to call it quits.
Posted by
K7PEH on 2005-03-29
Radiation Resistance
K7PEH: How can resistance be measured in watts?
A more correct definition of radiation resistance would be simply the real part of the antenna impedance at the frequency of interest.
Posted by
NI0C on 2005-03-28
K7PEH replies
NI0C asks a question --
K7PEH: How can resistance be measured in watts?
A more correct definition of radiation resistance would be
simply the real part of the antenna impedance at the
frequency of interest.
K7PEH responds ---
You misunderstood my comment. There is no such
"physical" thing as radiation resistance. That is,
measuring this in ohms as if it were some kind of resistor.
That is not the physics of what is happening.
What is happening is that there is power associated with
the radiated energy. The energy that is radiated by the
electromagnetic wave can be considered equivalent to an
I-squared R type of loss for the purpose of the radiation
resistance concept. The "R" in this case is not a real
resistance though you can "think" of it like that for the
simplistic view of the concept of radiation resistance.
I am not saying that R (resistance) is measured in watts. I
thought that was clear by the ohms law formulation that I
included.
As for your suggestion of the radiation resistance being
the real part of the resonant impedance -- I will have to
think about that some and maybe squander some time
with the mathematical formulation a bit (oh, not a
problem as math is my favorite love). However, your
notion of the impedance though does not separate out the
actual radiated energy (or, power times time) from the
other affects of the antenna which include true ohmic
resistance as well as the affect of nearby objects or
ground that will add to the loss due to both magnetic or
electric field interaction.
Phil (BS Physics, 1970)
Posted by
K7PEH on 2005-03-28
K7PEH replies
NI0C asks a question --
K7PEH: How can resistance be measured in watts?
A more correct definition of radiation resistance would be
simply the real part of the antenna impedance at the
frequency of interest.
K7PEH responds ---
You misunderstood my comment. There is no such
"physical" thing as radiation resistance. That is,
measuring this in ohms as if it were some kind of resistor.
That is not the physics of what is happening.
What is happening is that there is power associated with
the radiated energy. The energy that is radiated by the
electromagnetic wave can be considered equivalent to an
I-squared R type of loss for the purpose of the radiation
resistance concept. The "R" in this case is not a real
resistance though you can "think" of it like that for the
simplistic view of the concept of radiation resistance.
I am not saying that R (resistance) is measured in watts. I
thought that was clear by the ohms law formulation that I
included.
As for your suggestion of the radiation resistance being
the real part of the resonant impedance -- I will have to
think about that some and maybe squander some time
with the mathematical formulation a bit (oh, not a
problem as math is my favorite love). However, your
notion of the impedance though does not separate out the
actual radiated energy (or, power times time) from the
other affects of the antenna which include true ohmic
resistance as well as the affect of nearby objects or
ground that will add to the loss due to both magnetic or
electric field interaction.
Phil (BS Physics, 1970)
Posted by
K7PEH on 2005-03-28
WA6BFH Quiz (or, is this a poll?)
What is radiation resistance?
>>> is the measure of the power lost from an antenna in
radiation using the formula I-squared times R where R is
the effective radiation resistance. Of course, power lost
by radiation is what the antenna is supposed to do. Note
that the radiation resistance only has meaning when
expressed in ohms law formulation for power. Since it is
power of the radiated signal that is being measured.
What is the impedance of an antenna -- at its tip, and at
1/8 wavelength fractions of wavelength from the tip:
>>> I give up -- what is a tip? If it is a half-wave
antenna then the impedance of a resonant antenna is
minimum at the center where two 1/4 wavelength lobes
exist on each side. And, 1/8th of a wavelength is at the
half way point of that 1/4 wavelength lobe and the
impededance is roughly half way between the minimum
and maximum where the maximum impedance is at the
ends (is this the tip?).
Or, is it a bad idea to use a TransMatch with a non-
resonant antenna that is fed with a long run of coaxial
cable? If yes, why?
>>> It is bad with any kind of coaxial cable with losses.
The reflected power is sent back down the transmission
line and suffers loss along the way. But, that reflected
signal is also reflected by the transmatch back towards
the antenna and it suffers loss yet again. You can easily
compute your effective radiated signal based on knowing
the mismatch impedance and the loss of the coaxial cable
in dB.
Phil
Posted by
K7PEH on 2005-03-27
Convenient
My coaxial feed Windom is really multiband antenna since I use internal tuner of my TRX. For special needs I use homebrew manual matching unit that can tune everything and everywhere but is not convenient for everyday use.
For these transceivers without internal tuners I’d buy external one. Especially for mobile setup!
Auto tuners are convenient – that’s why we use them regardless of any possible lost, radiation of feeder, etc.
Posted by
UT7UX on 2005-03-26
Great accessory for portable operation when a resonant antenna isn't possib
I like to use a small manual antenna tuner for portable ops when a wire up in a tree or a less than ideal (and not exactly resonant) is all that I can manage. Also, on my tiny city lot, full sized antennas for 40, 60, and 80 simply aren't possible. A random wire and tuner still outperforms a grossly shortened vertical.
Yes, a properly cut resonant antenna is best and is most efficient. Antenna couplers still have their place.
73,
Caity
K7VO/8
Posted by
K7VO on 2005-03-26
Got two external ones; one of my rigs has a built in one.
Also got an FM tuner.
73
Bob
Posted by
X-WB1AUW on 2005-03-25
"Final " Savers
Antenna tuners are the tools of operators that don't know how to cut, lengthen, or otherwise modify their radiators for the lowest SWR, which relates to resonance. This stuff isn't magic,folks.
Regardless, I do have an "antenna tuner" in two of my rigs. The only antenna tuner that I would find helpful would be the random wire type, such as an EDX-2.Great for field day use.
Posted by
W4ABX on 2005-03-25
I have used one to load up the gutters around my house, has anyone else tried this..........
Posted by
W4ABX on 2005-03-25
What's in a name?
1. It does not tune an antenna, so why the name? Why do we call "cycles per second" "Hertz"?
2. It acts as a preselector for modern rigs with broadband front ends. Really improves image rejection.
3. It acts as a (relatively) narrow RF bandpass filter for transmitting, thus attenuating any spurious, out-of-band emissions.
4. With an imperfect antenna (say an 80 meter dipole cut for the CW end when you want to make an occasional QSO at the top end of the phone band), it allows modern transmitters to send full power to the still incorrect antenna, which is better than sending greatly reduced power to the still incorrect antenna. In other words, it allows you to make the most of a bad situation.
My Conclusion:
Call it what you may, even with a perfect antenna it is a useful accessory for modern rigs (and boat anchors, too!)
73 --
Joe, W3BC
Posted by
W3BC on 2005-03-25
TransMatch "Antenna System Tuner"
It might be interesting to ask by way of a poll:
What is radiation resistance?
What is the impedance of an antenna -- at its tip, and at 1/8 wavelength fractions of wavelength from the tip:
Or, is it a bad idea to use a TransMatch with a non-resonant antenna that is fed with a long run of coaxial cable? If yes, why?
Just a thought! 73! de John
Posted by
WA6BFH on 2005-03-25
Antenna Tuners
I'm old school too, just like KA9INV who says, "I am old school - can't afford an antenna "tuner", so I don't use one!"
Don't use what, an antenna or a tuner?
...and lips that touch liquor will never touch mine.
Posted by
W3QS on 2005-03-25
Antenna "Tuner"
Might there be some kind of "Impedance Matching" device that hams could use to "Couple" their "Non-Resonant" length antenna "Array" to their "Transmitter/Amplifier" "System" so that said "Antenna" and aforementioned "Transmitter/Amplifier" "System" could "Get Along" without all this "Sarcasm"? (Insert your favorite Rodney King quote here.)
There are some respondents whom I am glad to except from my comment... These hams are obviously on-post. Elitism has no place in ham radio. Nor does semantisism.
As some swabs have exclaimed, "Whiskey Tango Foxtrot?"
I have built my own coupling devices to match my radios to my own home brew antennas. Whatever they are formally and normally called, there is no need/call to belittle the thread/original poster...
Posted by
KF6HCD on 2005-03-24
Another KG4ECA Victim
Cheated me in Ebay transaction.
Write for details. Offered items, then a ton of excuses, now no replies to email.
Uses
shamusfl@yahoo.com as a drop.
Address is: Robert M Wasylik
18 Chippingwood Lane
Ormond Beach FL
Posted by
K5MO on 2005-03-24
Yes, to all
Like other posters, Tuner, coupler - heck, we ALL know it does not "tune" the antennaa, but tuner has just been used for so many years by so many folks, it's as good a name as any.
and as other folks mentioned, I need to answer YES to all the points - but the survey doesn't give me the option.
Posted by
K9FV on 2005-03-24
Antenna tuners
My antennas are basically resonant in the sections of the bands that I operate most often. Since my 160, 80 and 40 meter antenna is tuned for the CW section of each band I use a Drake MN2700 when I want to operate SSB. On 20 through 10 meters I have a multiband vertical tuned to the middle of each band. On those I use the automatic tuner in the radio when needed for band-edge excursions such as operating FM on 10 meters. Nothing fancy, but it works for me.
Posted by
KK9H on 2005-03-24
Antenna Tuner
I have two transcivers. One has a built in tuner on
the other I use an outboard tuner. Survey did not
allow me to comment both ways.
Posted by
W2UIS on 2005-03-23
Never mind "Tuner Lessons" -- how about "Polling Lessons"?
Here's a survey that asks a closed-ended question but that doesn't provide all of the possible answers.
I use BOTH my radio's internal tuner and an external tuner. When I'm on my Maypole (Fan Dipole) I use the internal tuner just to touch up at the band edges. For other antennas, I use the external tuner. In the center of the bands where my maypole is resonant, I use no tuner at all.
Reminds me of another poll, maybe it was here or maybe on the ARRL site, that asked where your "shack" was located. It left out "garage" as one of the possible answers. The garage is probably one of the most popular "not in the house" locations for a ham shack.
Closed-ended questions are great for the pollster, but need to be written carefully or the results are meaningless.
And by the way, neither of my tuners is called "Ralph" -- that name is reserved for the operator.
Posted by
K0RFD on 2005-03-23
Antenna Tuner Lesson ?
I am relatively new back into ham radio after being away
for almost 40 years. So, why do some hams have such an
issue with calling an Antenna Tuner, an "Antenna Tuner".
Do I think that I am tuning the antenna when I use my
antenna tuner? No, I am I only doing one thing. I am
inserting a box between my final and my antenna. The
purpose of this box is to reflect the signals back to the
antenna that the antenna reflects back down to me.
So, why do I do this little thing. It is because the antenna
says to my signal "I am only taking 70 percent of your
signal but I am sending the other 30 percent back to you
and you can try again if you want". So, I have this nifty
box that will send that 30 percent back to my antenna to
transmit again. The antenna says "I am only taking 70
percent of the 30 percent signal that you are sending back
up to me and sending you 30 percent back of that 30
percent reflected signal. And, so my nifty little box does
its reflection thing and I keep doing this until --- well,
until I run out of signal.
Of course, there are losses that prevent this perfect
arrangement. If there were no losses at all, then all 99.9
(or some delta less than 100)
percent of my signal will get transmitted (in phase) just
fine.
So, that is the purpose of this little box. But, what do we
call it. Well, let's examine what it does. First, it sits
between my final (amp or transmitter) and my antenna.
Somehow I want to include that fact in the name. Second,
is that using this box does involve creating a match
between the output and my transmission line. The act of
creating this match is called "tuning". Everyone agrees to
this. So, I could call it my transmitter tuner, amplifier
tuner, final tuner, or antenna tuner.
Somehow, I think that antenna tuner makes the most
sense so I will use that term.
Posted by
K7PEH on 2005-03-23
Tuner? Bah!
I am old school - can't afford an antenna "tuner", so I don't use one!
Posted by
KA9INV on 2005-03-23
Semantics
I don't use an "antenna tuner" at all. No need to at this point. My antenna 'must' have been perfectly resonant to the extent that my internal tuner would churn and click for upwards of 20 seconds before the power on the radio for some 'unknown' reason just cut off. Determined to use it as I paid extra so as to avoid an external one, I continued to attempt to tune the resonant antenna with the same incessant clicking just prior to the rig shutting off. I did smell a funky kind of burning odor but assumed it was simply the soldering iron I left plugged in some 30 minutes earlier downstairs on my wooden kitchen table. Thus, I ignored it as any reasonable fool would. Frustrated, I decided to go outside to double check my randomly cut longwire antenna that I cleverly attached to a sturdy transformer some 30 feet up a nearby telephone pole for safety-grounding measures. After ensuring the longwire resonant installation was still in tact, I opted to walk around to the front of my home as some blaring fire engine sirens had piqued my curiosity. To make a long story painfully short, I no longer use my longwire configuration nor the radio with the internal tuner as both were rendered useless.
What was the topic of primary focus again?
Posted by
AI4IT on 2005-03-23
Needs more choices!
We need these choices also:
Yes - internal to Radio AND and and outboard type
Yes - a self tuning antenna (screwdriver/StepIRR)
Yes - internal to Radio AND a self tuning antenna (screwdriver/StepIRR)
Yes - an outboard type AND a self tuning antenna (screwdriver/StepIRR)
Yes - all three types
---------
In my case, I have to enter all three types
Dennis / KG4RUL
Posted by
KG4RUL on 2005-03-22
No Such Animal
There's no such thing as an antenna tuner; they
are antenna matchers or antenna couplers. Darn
these idiots, in and out of the industry, who can't
use the correct terminology!
Yes, I have an internal matcher in my rig as well
as an external unit.
Lon
Posted by
N3ZKP on 2005-03-22
No Such Animal
If the world knows it as "antenna tuner," it's an "antenna tuner." It's a defined term. If a coupler were known as "Ralph," then it would be a "Ralph."
Paul AB0SI
Posted by
AB0SI on 2005-03-22
Ralph
I use Ralph also. You can tun-a fish, but you can't tune an antenna.
73
UG
Posted by
URBANGORILLA on 2005-03-22
Tools
Sure I do, sometimes. Just another tool, like a wrench or diagonal cutters: And now that I think about it, I also use those to tune my antennas.
WB2WIK/6
Posted by
WB2WIK on 2005-03-22
I use both internal and sometimes an external tuner...depends on the antenna I am using. The survey did not allow me to make this clear. Sam W8VVE
Posted by
W8VVE on 2005-03-22
Jeeeshh!
Technical, technical, technical. It's the button that pick's up where the antenna design leaves off.
Dan.
Posted by
N1GXC on 2005-03-22
At least I know that an 'antenna tuner' really does tune my antenna, making it resonant on all frequencies at all times AND since the VSWR is 1:1, the radiation pattern is greatly improved and of course the gain is at least doubled (15 dB, right?). PLUS, I can feed any antenna with cheap coax at any power output because the antenna tuner will transform the cheapness into goodness (I think this is called 'Q'?).
I have a special design tuner that reduces the VSWR to 0.9:1, giving not only a huge power gain but reducing the noise figure of my receiver by at least 15dB (one-half the noise is 15dB).
Couple a very small-scale antenna to a receiver with this antenna tuner and you get NOISELESS reception. It even tunes-out the atmospheric noise by something called 'phasing'.
Every ham knows this.
Posted by
N4SL on 2005-03-22
ANTENNA COUPLER/MATCH
IF YOU BELIEVE THERE IS SUCH A THING AS A ANTENNA TUNER, THEN I HAVE A DEAL FOR YOU. ITS A BRIDGE IN NEW YORK, I'LL SELL IT CHEAP.
Posted by
K7NNG on 2005-03-22
Spit out that hook, boy.
Posted by
N4SL on 2005-03-22
Bridge
NY7Q, the Brooklyn Bridge has been sold many times over. By now there are so many owners that the Bridge is practically worthless, despite its age. Why not put the Verrazano-Narrows Bridge up for sale? You'll get a lot more for that one. Or, how about the Golden Gate? Tell 'em that its real 14 Karat. Tell 'em you'll even throw in an antenna tuner! :)
73
UG
Posted by
URBANGORILLA on 2005-03-22
As Per Kurt Sterba
YUP they actually tune the Antenna System, as Mr Sterba, World Radio..
Posted by
N6AJR on 2005-03-22
Let's not knock bridges
I recall reading about a group of amateur operators who roam the country side looking for bridges to load up as antennas.
Dennis / KG4RUL
Posted by
KG4RUL on 2005-03-22
antenna tuner
you guys slay me some times. dont you know some poor guywho dont have all his herz mightcome by and read this. lol
Posted by
WB4TGT on 2005-03-22
Let's not knock bridges
"I recall reading about a group of amateur operators who roam the country side looking for bridges to load up as antennas."
How about railroad tracks? Great longwire antenna!
73
UG
Posted by
URBANGORILLA on 2005-03-22
My choices!!!!
I have both, an internal to radio AND an external one...I only use the HI-POWER EXTERNAL one, never the internal...The EXTERNAL serves all purposes (my radio doesn't go above 100-watts)
Posted by
KC8Y on 2005-03-22
Tuners
All that a tuner does is fake your finals into thinking that they are happy. No magic whatsoever. And it also does not mean in this case that resonance equals efficiency. Personally, I prefer no muss, no fuss, full size resonant antennas. It gives you one less thing to worry about especially if the tuner is an MFJ.
Posted by
K1OU on 2005-03-22
Antenna Tuner
My Icom AT-180 Automatic Antenna Tuner is amazing with the Icom IC-706 MK II G. However, since I'm just old fashioned, I'd rather use my MFJ 949-C tuners (2) with my boat anchors: Swan 400, Hallicrafters HT-40, Swan/Cygnet 260. A quarter of a century ago, I didn't even have a tuner. I would cut the dipole exactly to center frequency and carefully load the Swan 400. As long as it was "loaded" correctly, it really didn't need a tuner. Nevertheless, I use one all the time now to save wear and tear on those (expensive) tubes! And, I am very amazed at what this Icom AT-180 Automatic Antenna Tuner is capable of with the 706. It quickly tunes just about any band - close to 40 meters - using my inverted vee dipole with W2AU Balun...apex is only 20'. I have a preference for the inverted Vee...I've had quite a bit of success with it. My last DX QSO was EA6UN Balearic Islands - Spain.
73 Yisrael KA5PNE
Posted by
KA4PNE on 2005-03-22
Tuner? Yes
Sure do use one. A link coupled tuner made from junk parts build in an old rack box. I have a 40ft wire in the attic and the radiator system in the house as the couterpoise. There is no feedline of any type between the tuner and the wire ant. I only receive on this setup.
Posted by
KE1MB on 2005-03-22
Well, here come the tuner "lessons" . . .
Most of us know that a tuner only fools your transmitter into thinking a good match has been achieved. Not everyone has the ability to erect an antenna for every single band we operate on. Therefore, tuners are a way to utilize a single (in some cases) antenna for multiple bands. We all know it isn't the most efficient way to operate but it does work. Maybe not as good as "your" setup, but it does work.
I just hope we're all saved the tuner lesson though. Of course, if someone asks what a tuner does then that's different . . .
Posted by
YEPSURE on 2005-03-22