Saturday, June 8, 2013

SUPER "C" A 21st Century Antenna


          For  the  past 80 or 90 years an antenna had to be 1/4 or 1/2 wave long to establish  resonant operation.  If a shortened version was required, an inductor was inserted to replace the "missing length."  Further, if an antenna's length has been significantly reduced, one must accept degraded performance i.e. less than 100% efficiency and in most instances much less than 100%.  NOTHING HAS CHANGED IN 90 YEARS.

          One can hear it now --- "Its been the sole solution for all these years, it must be the solution."  If there was a real alternative, we would have seen it years ago."  Well, GAP apologizes for being late but there is another real solution.  GAP has proved an antenna does not have to be 1/4 or 1/2 wave long to resonate.  You can forget the huge coil.  Not only does Super "C" confirm this, Super "C", in addition, establishes a number of truly unique and advantageous qualities.

          What is a Super "C"?  It is a radical change to H.F. antenna design.  It is the first fundamental change in over 50 years.  The typical, tall, vertical aluminum mast is gone, and replaced with a short, large diameter, aluminum mesh cylinder.  The cylinder has been "squared" forming a basket.  The basket is placed above a very short thin conductive mast.  The basket/mast assembly is, in turn, placed above a collector-grid of aluminum mesh.  The radius of the collector-grid approximates the height of the basket/mast assembly.  The collector-grid, for the moment, can be assumed to replace the typical radial configuration.  Its characteristics; however, are entirely different and it is dramatically smaller.  A 20 meter Super "C" version is shown in the figure.  It is 3 feet high!!!!  The collector-grid is very small,  six feet by six feet.  To put this in perspective, radial system for a 20 meter vertical, would be 35 feet in diameter.

          The well known antenna family of wire/rods are magnetic field dominated or MDR.  They have very little surface area and require a length such that electron current flow created by an RF source, such as a transmitter, will have sufficient length to continue to flow upward or outward on the wire until the RF source changes phase reversing the current flow.  The longer the "on" cycle (the lower the frequency) the longer the wire must be.

          The Super "C" design replaces this wire/rod with a large surface area mesh in the form of the basket.  The basket is positioned above a flat aluminum mesh surface, the collector-grid.  These two elements combine to form a huge capacitor which in turn creates a large electric field.  The large surface area provides space for the electrons to collect during each RF cycle.  This antenna is a E field Dominated Radiator or E.D.R.  From a resonance standpoint the capacitor dramatically reduces antenna capacitive reactance.  It is reduced until its, reactance matches the small inductive reactance of the short mast. When matched, you have a resonant antenna. 
     Maxwell and Poynting, pioneers in electromagnetic radiation, in the late 1800's developed the basic equation EXH=S.  The E field vector "crossing", or interacting with the magnetic field vector H, produces EM radiation S.  Both fields must be present.  If one antenna has a large magnetic field 10H and a small electric field 2E, radiation is 10H X 2E = 20S.  If instead, the antenna has a large electric field, 10E, and a small magnetic field, 2H, radiation is still 20S.  The output is the same, but the antennas are very different.  Somewhat like the tube and the transistor, both provide gain, but they sure are different.
           To understand the major difference between these antenna types, MDR and EDR, we go back to high school physics.  In high school, the instructor attached a loop of wire to a sensitive meter.  The instructor then pulled this wire across a horseshoe magnet.  The meter deflected!!  Electron current was caused to flow in the wire by the magnetic field - a galvanometer.  No one yet knows exactly how, but it does.  Now for an experiment that was not done.  We are going to charge two close spaced (1") copper plates with 50 volts and then drag the same wire between the charged plates in its E field.  What happens???  NOTHING!!!!  An electric field does not cause current to flow in a wire.  This very basic characteristic makes the two antenna types, EDR-MDR, vastly different.
          Of the many unique Super "C" characteristics three are of great significance;


          Immunity is an integral characteristic of an E field antenna because its magnetic field is small.
         The MDR Antenna is its own magnetic generator inducing current in anything conductive near it.
           Super "C" or EDR, absent a large magnetic field, produced the following test results on 20m:
 1)   A 33' aluminum mast was placed within one foot of the Super "C" collector-grid.  Super
                   "C"  VSWR of 1.0:1 did not change.  There was no disturbance.
 2)   The Super "C" was relocated adjacent to a steel wall 18 feet high and 50 feet long.  At a
                    distance of three feet the VSWR 1.0:1 did not change.  At 2 feet the VSWR increased to
                    1.5:1.  Hard to believe!!!, but true.
 3)   The antenna was then placed inside a steel building.  The Building had no windows, steel
                     roof, sides, and doors.  All doors were closed and 100 watts was applied to the antenna.
                    The antenna remained resonant and VSWR at 1.0:1.
 4)   A second test antenna has been operating now for months in an attic over a residential
                    garage.  It is 2 feet from the attic light and positioned between the trusses, over the
                    house wires, the garage ceiling lights and the garage door opener.  The transmitted power
                    was 100 watts.  The sole interference detected, was on the portable (40 MHz) phone!!
                    Prior to attic operation, the Super "C" had been placed 5' from a GAP vertical.  Neither
                    antenna detuned the other.
 Earth Loss - The surface area of the collector-grid is much larger than the basket.  Actually about double. The capacitance equation clearly states "do not expect more capacitance than that from the smallest area", or in this case the basket.  Thus, the antenna does not look "beyond" the oversized collector-grid or the ground.  A second factor is the charge on capacitor plates is only on the sides that face each other, thus the under side of the collector-grid is "NEUTRAL".
           Rationales are interesting, but does the  real world confirm? A Super "C" antenna was mounted on a three foot insulated mast,  and matched to a 1.0:1 VSWR.  The antenna was then raised to 11 feet, and  the VSWR did not change.  If the Super "C" had picked up some Earth loss at three feet, it would have diminished at 11 feet and the resultant VSWR should have increased.  Since it did not the conclusion can be drawn that Earth loss would not be a factor. The antenna was then lowered directly to the ground and VSWR was measured once again and no change was indicated. 
           To verify that the underside of the collector-grid is neutral, take  a fluorescent bulb and while transmitting, touch the bulb to the top side of the collector-grid at the edge and it will light.  Now place the bulb on the under side of the grid and touch it to the edge and it will not light. The antenna resistance was measured and calculated at 2.8 Ohms.  Which leaves little room earth loss.
           Efficiency - The large capacitance inherent in a Super "C" drastically reduces the antenna’s capacitive reactance thus eliminating the need for a large coil.  A very small coil, four turns of two inch diameter is used on 20 meters.  This small air wound coil is virtually loss less.  This and the absence of earth loss results in an antenna efficiency that approaches 100% in spite of its low profile.
           The Super "C" was A/B tested against a full size 17 foot conventional vertical with three insulated full 1/4 wave radials.  At no time did the signals received on the conventional vertical exceed the Super "C"’s.  On numerous signals, the Super “C” was as much as two “s” units stronger.  If 60 1/4 wave radials (1020 feet) were deployed, it would have decreased earth loss from 35 Ohms to four Ohms increasing the conventional vertical's signal by half  an “s” unit, but still less than the Super "C".
          What you have just read is just a very small portion of the Super "C"’s characteristics.  As time passes, what we know today about EDR antenna will have been just the tip of the eventual iceberg.


A 21st Century Antenna

Background - For a century vertical antenna designs have adhered to the relationship that their 1/4 wave length or height is determined by dividing the desired frequency of operation in megahertz into 246.  This relationship stems from the speed of light and is, of course, still valid in establishing the length of linear antennas of the wire, rod, or tube configuration.  Antennas in which the diameter of the wire, rod, or tube is very small compared to its overall length - typically 1:500 or less.  To complete the antenna, with reasonable operating efficiency, requires that a significant number of radials be placed beneath this vertical.  Commercial station verticals most often contain as many as 100 to 120 wires extending a 1/4 wave distance from the vertical and surrounding the vertical, Figure A is typical.

Short Antennas

There are, however, many situations where the height dictated by the "246" equation cannot be accommodated, or is impractical, or is just plain undesirable.  A good "short" antenna has always been an objective.  The time-honored short antenna solution has been - "Remove that portion of the antenna that was not wanted."  In the minds of most, having eliminated a significant length of antenna, form the discarded length into a coil and insert this coil into the shortened antenna.  The amount of coil needed will vary some depending on where it is inserted (bottom or middle) but the technique is basic. see figure B.  If there was any doubt that this was the proper technique, that was confirmed by measuring the input impedance of the shortened antenna without its coil.  That measurement indicated that a large capacitive reactance, Xc, existed in the short antenna.  Thus it was logical to insert a large coil with its large inductive reactance, XL  , that could balance the large capacitive reactance, Xc   = XL   , thereby, establishing a resonant condition in the short antenna.  The added length introduced by the coil tends to make one believe that the "speed of light" length remains satisfied.

Reasons for change

Although used for decades, there are a number of well known, significant, shortcomings with this technique.  First - inserting the large inductor establishes a very large reactance in the antenna and in turn that results in inescapable, unwanted, narrow band performance.  As a user moves the operating frequency from resonance (where XL  = Xc ) the unbalanced reactance, X, becomes very large, very rapidly and quickly increases the Voltage Standing Wave Ratio(VSWR) beyond the 2.0 to 1 limit.  If the short antenna's bandwidth must be increased, the only way to accomplish this is to add a loss resistance to the antenna's basic radiation resistance Ra.  This added loss, however, reduces antenna efficiency and degrades signal performance.  Loss will come from a poor radial system i.e. few radials or using one's automobile body for radials, etc.  Loss also comes with poor coil design.  Coils wound with small diameters (an inch or so) with metal end caps (shorted turns) and with contiguous windings are well known factors that result in loss.    Second - The large inductive/capacitive reactances generate very high voltages, i,e, corona, which curtail reliable operation in adverse weather i.e. rain, snow, ice, etc.  The short antenna's low resistance and resulting high RF current often preclude maximum power operation. 

Over the years, countless articles have been written on "How to improve" the performance of the shortened vertical.  The thrust of the articles has been how to reduce antenna losses.  A careful look at what someday might be the "ultimate" zero loss antenna is an eye-opener.  Admittedly fictional, using superconductor wire, a wide diameter and adequate turn spacing produced a zero-loss coil.  An 80 meter, 8 foot, antenna with the loss free coil is now placed over a backyard of copper screening to maintain loss free operation.  An 8 foot 80 meter antenna has a radiation resistance of 1/2 Ohm.   The loss free coil with its many turns generates about 1900 Ohms inductive reactance, XL  , producing a quality factor, Q, of 1900/1/2 or 3800.  A Q of 3800, in turn, establishes a bandwidth on 80 meters of (3.5 megahertz divided by 3800) 900 Hertz.  900 Hertz will not even pass the 2300 Hertz audio from our SSB transceivers let alone accommodate any frequency shift without continuously retuning the antenna.  This "ultimate", truly efficient, short antenna is virtually useless.  No sensible user would want one.  Is there possibly a truly better solution?   Not one that accents loss and reduces efficiency dramatically.  This question has been asked for years and still is.  At long last, the answer is finallyyes-there is a different and vastly improved solution.  One without smoke and mirrors.

Restart with basics

Starting simple - a vertical antenna is in reality a simple series R-L-C resonant circuit.  The vertical wire, rod, or tube is the inductor, L.  The same vertical mast, in combination with the radials, forms the capacitor, C.  Completing the circuit is the antenna radiation resistance Ra.  Antenna radiation resistance varies with the length of the antenna.  It shrinks as antenna length shrinks.

When an antenna height or length is shortened, its inductance is reduced.  When antenna height or length is shortened its capacitance is also reduced.  Sounds simple.  What this means is that respective reactances XL and Xc   (inductive and capacitive) diverge.  Why?  When the antenna height is shortened inductive reactance, XL  , becomes smaller because inductive reactance XL  , is equal to 2pFL

where p = 3.14, F = frequency in Hertz and
            L = inductance in Henrys
As L decreases obviously XL decreases.


Capacitive reactance, Xc , on the other hand, becomes larger because capacitive reactance Xc  , equals   1 / 2pFC         where p = 3.14 F = frequency in Hertz 

C = capacitance in Farads.

As C decreases, Xc , increases.  Why is that significant?  When the input reactance of the shortened antenna was measured, it was heavily capacitive, but that same short antenna still possessed some inductive reactance.   Reactance generated by the remaining shortened mast!   Reactance covered up by the large capacitive reactance created by the very small capacitance of the shortened mast.  Many published curves of input reactance are erroneously labeled capacitive when they should be labeled as the "difference" reactance, Xc  - XL

Super "C" Antenna Approach -

The Super "C" patented antenna design uniquely solves the short antenna problem. It achieves resonance, not by adding a coil but by dramatically increasing antenna capacitance until its magnitude develops a capacitive reactance small enough that it matches the small inductive reactance of the short antenna.

How can antenna capacitance be increased?

There are two candidate approaches.  The most obvious was to add a capacitive hat.  The well-known capacitive hat was not selected because the current that flows on its surface does not produce RF radiation.  RF current flow on the hat is from the center outward radically in all directions, (Figure C), and on the reverse cycle from its outer edge back to the center.  Figure D.  In both cases, there are always equal and opposite currents.  That is, current flowing North is balanced by that flowing South.  The same is true of the other spatial directions - east vs. west etc.  Hence, it does not radiate.

Because the cap hat does not radiate RF, its size is unable to contribute to the short antenna's radiating length.  Antenna radiation resistance in shortened antennas is quite small and the cap hats inability to increase antenna length and thus its resistance is a significant negative factor and it was discarded.

The Super "C" antenna uniquely (Patent#  5,796,369) employs a very large diameter vertical cylinder.  The diameter of this cylinder is 30 to 100 times larger than the diameter of the antenna mast.  See figure E.  The total current on the surface of this vertical cylinder is in one direction - vertical.  Up and down in sync with RF current flow on the mast.  Since there is no counteracting current, cylinder current adds to the overall antenna radiation.  This is important because the cylinders height can now be added to the mast height increasing total antenna height and in-turn antenna radiation resistance, which is crucial.  The cylinder and mast are shown in Figure E.

The total capacitor

Placing a large vertical cylinder on a short mast does not in its self create a capacitor.  A capacitor obviously requires a minimum of two surfaces. The cylinder is one surface.  To compliment the cylinder and form a low profile capacitor, a flat conductive plate is placed beneath the cylinder and its support mast see Figure F.  The plate has been designated collector-grid.  Collector because it collects or completes the E field with the cylinder grid because it is not a solid plate but a grid structure whose pattern is approximately 65% air.  The collector-grid has a nominal radius, centered at the base of the mast, extending out a distance equal to the height of the antenna.  It is obviously very much smaller than using conventional 1/4 l radials - approximately 900% smaller!!!

A specific Super "C"

The Super "C" antenna in Figure G operates on the amateur bands from 20 meters to 10 meters.  It is 3' in height and its collector-grid is 6 feet by 6 feet.  It uses a "squared-up" cylinder 27" on a side because that profile is simpler to fabricate and assemble and survive in wind conditions.

The Super "C" does use a very small inductor on 20 meters.  Four turns of a 2" diameter coil.  This is significantly less than the time honored approach.  For example, an 8 foot, 20 meter antenna, 250 percent larger than the Super "C", requires a coil that is 300 percent larger e.g. 10 turns.  The Super "C" - 20 antenna operating on 12 meters requires no inductor - just a straight connection.  Actually the antenna is naturally resonant on 19 mHz even though it is 400% shorter.  The Super "C" operating on 10 meters with its 3 foot height is too large and requires a discrete series capacitor instead of an inductor to reduce the capacity established by the cylinder to achieve 10 meter resonance.

Super "C" Antenna Characteristics

As unique as the tiny antenna may appear visually, its performance characteristics are even more unique.

To validate these characteristics one needs to return to high school physics.  A simple experiment was performed by the physics instructor.  He was to connect a loop of wire to a sensitive dc meter, then drag the wire across a horseshoe magnet and observe the meter deflected indicating a current flow in the wire caused by the magnetic field of the magnet.  The linear wire, rod, tube antennas we have known for years are magnetic field dominated antennas they generate a magnetic field with current flow and generate a current when exposed to a magnetic field.

Maxwell and Poynting in the late 1800's developed equations for electromagnetic radiation.  Most important was the equation that E X H = S - that is an electric field vector, E, "crossing" a magnetic field vector, H, produces radiation S.  Further, that a large "H" crossing a small "E" produces the same output that a small "H" crossing a large "E" produces.  The large "H", small "E" antenna is the magnetic field dominated antenna i.e. MDR..

The latter is an "EDR" - Electric field dominated antenna.  The Super "C" is an EDR type antenna.  The experiment not performed in that physics class was to take 2 copper plates (typically 12" X 12").  Separate them by one inch and charge them with 100 vdc.  Slide the same wire between them (Wire is insulated!!) and drag it.  Did the electric field also generate a current???  No, it did not.  Magnetic fields couple - electric do not!!!!

Signal Sensitivity/Efficiency

Antenna efficiency directly establishes signal sensitivity and antenna loss in turn directly controls efficiency.  Loss is the key.  There are two potential sources of loss in the conventional and Super "C" verticals.  Coil loss and earth loss.

Coil Loss

It is obvious that the Super "C" with its minimal 3 turns on 20 meters, 2 turn on 17 meters and no coil on 15, 12, and 10 meters has virtually no coil loss.  Conversely, the coil loss of  large multi-turn coils  required in conventional short antennas can be significant.
Earth Loss
Earth loss occurs in the vicinity of the ground plane with conventional linear antennas.  It is significant unless large numbers of radials are employed and elevated.  This requirement in most areas is impractical.  In locations with adequate space, implementation efforts are significant and usually deter the user.  In the case of the Super "C", earth loss if present must occur in the vicinity of the 6' X 6' collector-grid.  It is firmly believed, however, that earth loss is not a factor in the Super "C" because:

            a)         The surface area of the collector-grid although very small is twice that needed by the cylinder.  As such, the E field created has no need to seek any thing beyond the collector-grid physical limits.  The very close spacing between cylinder and grid of 1 foot compacts the E field.

            b)         The collector-grid was elevated 2 to 3 feet above ground on an electrically isolated support mast.  Distancing the grid from ground.

            c)         To confirm zero earth loss, the following test data was collected.
The Super "C" 3 feet above ground was tuned to 20 meters and adjusted to a 1.0 to 1 VSWR.  Antenna resistance was 2.8 Ohms - calculated and measured.  (At 2.8 Ohm its not possible to contain very much earth loss).  A shunt capacitor was used to transform the 2.8 Ohms to 50 Ohms.  The antenna was then elevated from 3 feet to 12 feet and the VSWR recorded again.  The VSWR did not change.  It remained at 1.0 - 1.  Had there been any earth loss at a 3 foot height, raising the antenna would have reduced that loss and changed the recorded VSWR.  It did not - hence no earth loss was present when operating the Super "C" at the 3 foot level.  Keeping in mind that since a 10:1 transform was used, even a 1 Ohm change multiplied by 10 would have been readily noticed.  In summary, the losses in the Super "C" are negligible and as a result its efficiency approaches 100%.

The Super "C" was then lowered to ground level.  The VSWR was again measured.  It remained at 1.0 to 1 indicating no Earth loss had "crept" into the antenna with collector-grid right on the ground.  Can this be explained??  There are two factors that support earth loss immunity.

1)         Earth loss on conventional radials has been depicted as a di-electric loss in coupling (capacitive) from the vertical mast to its slender radials.  Instead, it is believed that the loss occurs when current flows on the radial, the lower half of the magnetic field created is caused to operate in the lossey dirt.  If this is correct, it would explain why elevating the radials a foot for, example, does not eliminate the loss.  That is because the magnetic field extends outward in all directions from the radials.  The collector grid virtually eliminates an earth borne magnetic field because its basic structure and current flow does not produce a magnetic field no more so than a magnetic field is produced on the surface of a variable capacitor.

2)         The surface of the collector grid charges and discharges in sync with the input RF source.  It is basically one side or plate of a capacitor.  The charge exists between this grid and the mesh basket.  Current flows on the surface of these two sides.  Current does not flow on the under side of the grid (i.e. ground side) nor does it flow on the inside of the basket.  Thus, since the collector grid does not use the under side of the grid, it does not introduce earth loss into the antenna.

On Air Tests

The very high efficiency is borne out with "on air" signal comparison measurements.  Although initially expected to out perform shortened linear antennas, early on, it was realized that small size is really not a negativefactor and that a 3' Super "C" will perform on a par with any  full size vertical antenna.  Tests were therefore conducted relative to full size vertical center fed dipoles.  Center fed vertical dipoles were used to avoid extensive radials and  losses associated with less than the optimum numbers of radials.  An efficient vertical was necessary to obtain a true evaluation.  "On air" tests show no discernible difference between Super "C" and the vertical dipole.  At some times and some distances the dipole was a few db stronger.  At others, the Super "C" was stronger.  Considering that texts show a vertical dipole should be about 2db stronger than the vertical itself,  the performance of the Super "C" exceeded all expectations.  The Super "C" theory and performance has established that small size is not a consideration.  Kraus in his book did show that a 1/2 size dipole antenna might expect reduced received signals of a few percent which would not be discernible on on-air tests.  Although difficult to adjust to, "bigger is better" is no longer a factor.   At last one can finally dismiss that old comment "A vertical is a device that radiates equally poor in all directions."  A test was also run against an 8' commercial mobile antenna mounted and matched to an automobile.  On some 20 meter signals the mobile antenna did get within a few db's of the Super-C; however, the majority of signals were down 12 - 18 db.  The mobile antenna was not competitive.  The mobile antenna was a well known commercial unit.

Near-Far Fields

One might consider this factor to be of minor importance.  With the Super "C", it is extremely important.   The beam developed from an antenna begins to form at the far field boundary.  Inside that boundary a collapsing magnetic field exists.  Its presence is confirmed by observing the mutual coupling between conductive objects in this field and the powered antenna.  On the positive side, it is mutual coupling that allows a driven element (dipole) coupling to a director and a reflector that creates antenna gain and front to back attenuation.  The result is the well-known 3 element beam (i.e. a Yagi).  On the negative side is the unwanted couplingbetween items like downspouts, aluminum posts on screen porches and pools and of course aluminum sided housing, etc. that corrupt the tuning and matching of verticals placed near-by.

How do the far-field limits compare between the standard 1/4 l vertical and the Super "C".  
The far field equation is :      

2(L) 2

20 Meter Vertical Dipole:  
2 (36')2 /68 = 2 (1296) / 68 = 2592/68 = 36 Feet
20 Meter Super “C” 2 (3')2 / 68 = 18 / 64 = 4 Inches!!

Equations are informative - Test data, however, can be more meaningful.  Two significant tests were run on the Super "C".

Test (1) - The Super "C" antenna was tuned and matched to a VSWR of 1.0 - 1 on 20 meters.  A 32 foot vertical aluminum tube was then placed next to the antenna.  At a distance of 3' from the collector-grid, the VSWR did not change indicating no mutual coupling was occurring with the 32 foot tube.  Next, the tube was moved to 1 foot away.  Still no change in VSWR.  At 6" the VSWR increased to 1.8 - 1. Indicating some coupling.

Test (2) - Encouraged by the immunity shown in test (1), the antenna was tuned to a VSWR of 1.0 -1 in an "open" area.  The antenna was then moved to within 5 feet of an 18 foot high 50 foot long steel-sided building.  A worse situation is difficult to imagine considering the Super "C" height of  3 feet.  At a distance of 5 feet, the VSWR on the antenna remained unchanged at 1.0 - 1.  The same at 4 feet.  At 3 feet the VSWR increased to 1.5 - 1.  Still usable - but indicating some mutual coupling was occurring at 3 feet!  Clearly, the very short near field is providing the antenna with extraordinary immunity to its surroundings.  It is a critical feature to users with extremely limited space in which to locate an antenna.  The installation possibilities are now endless!


As noted earlier, bandwidth is a function of the reactances of the antenna.  Large reactance leads to narrow bandwidths.  The Super "C" with its very small reactance established by the short mast and cylinder and its reasonable antenna resistance of 2.8 Ohms on 20 meters produces a broadband antenna.  This differs from the inductive loaded (coil) short antenna whose broad bandwidth occurs only with excessive losses.

The following are typical Super "C" 2.0 -1 bandwidths:

            mtrs - bw                                 mtrs - bw
            20        300 khz                        12        1.0 megahertz
            17        400 khz                        10        1.4 megahertz
            15        700 khz                        
Based on the above data, the Super "C" does not require tuning on any band of operation which makes the antenna far more user-friendly than existing 8' antenna units.


DX-operation is a compound word that denotes the ability of an antenna to transmit and receive low elevation angle RF energy to and from the ionosphere when the antenna is located close to or on the earth's surface.  A fundamental vertical has the inherent ability to operate at zero degrees elevation angle but only when the area surrounding the antenna is or has a conducting surface like saltwater or copper screening.

Sir David Brewster in the 1800's stated that the phase of low elevation angle signals striking a reflecting surface is corrupted if that surface is lossey  e.g. typical ground.  Neither the conventional nor Super "C" antennas avoid this effect.  The Super "C", with its 3 foot height, does have an advantage.  If a user elects to increase low angle performance by placing conductive screening around the antenna, how far out from the antenna must the ground be covered for 5 degree operation?  The Super "C" with its short 3 foot height requires 30 feet frontal coverage.  A 17 foot quarter wave vertical on 20 meters because of its height requires frontal coverage out to 150 feet.  Convincing a neighbor that copper would look good in his yard may be difficult!!  Is placing conductive material worth the effort?  Signal increases approaching 10 db maybe realized with conductive screening on low angles DX signals.  It's worth it!!!


The Super "C" design concept is fundamentally simple.  It will probably result in a new set of equations which specify antenna design independent of length.  It is expected that experts in the H.F. field will develop and quantify theories to explain some of its unique characteristics i.e. antenna resistance, mutual coupling, design elements capacitance and inductance and phasing etc.  One rudimentary antenna characteristic, however, still remains - "Any conductor, regardless of shape, size etc. if it is not connected to nor does it contain any loss elements must radiate all the energy supplied to it".  Why?  Because that conductor has no other way to rid itself of the input power to it.  Size does not degrade radiation-loss does.  The Super "C" confirms size by itself is not a limit to efficient transmission and reception of RF energy.

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