For One and All,

Thank You "JP" for bring the IsoTron Antenna
website to my attention.

The IsoTron Antenna represents an interesting Antenna design
and build techniques for an compact Transmitting (and Receiving)
Antenna to be used in small Spaces and locations where there are
physical limits to work within. ~ RHF
http://groups.yahoo.com/group/Shortw...a/message/9031

IsoTron Antennas -by- Ralph Bilal (Bilal Co)
http://www.isotronantennas.com/index.htm
HF Antennas designed and built for {small} Spaces
Designed and Built-by Ralph Bilal (Bilal Co)

How Do ? - The IsoTrons Antennas Work So Well?
http://www.isotronantennas.com/isohow.htm
The IsoTron Antennas are Electrically Resonant
by using only two components - the Large Coil
in Series with the Capacitive Plates that are
the center {main components} of the Antennas.

IsoTron Antennas - Photos
http://www.isotronantennas.com/photos1.htm

IsoTron "AM Broadcast Band" Antenna
http://www.isotronantennas.com/ambroad1.htm

Reference Message -by- "Jack Painter" *t
http://groups.yahoo.com/group/Shortw...a/message/9019

"RHF" wrote in message
oups.com...
Carter [k8VT], - You probably tell kids
that there is "NO" Santa Claus ;-( ~ RHF
.
.
. .
.
The consensus is that the coax is the actual radiator; the "antenna" is the
matching network. The longer the coax, the better it works.
The original analysis may still be available on the AntennEX forum if you
are a member..

Dale W4OP

Carter-K8VT wrote:
RHF wrote:

For One and All,

Thank You "JP" for bring the IsoTron Antenna
website to my attention.

The IsoTron Antenna represents an interesting Antenna design


Interesting maybe, but a IMHO just a little bogus. Just some funky
shaped sheet metal.

Read the 'Aerials' column by Kurt N. Sterba in World Radio magazine and
see how many countries he has actually worked using either a lawn chair
or a shopping cart as an antenna, the point being that *any* chunk of
metal will work...(maybe not *efficiently*, but it will work).

No always so inefficiently; My radio club while teaching elementary
school multiplied the range manyfold of our 100 milliwatt AM station on
1200 khz, when one of the kids hooked the antenna to the steel doorjam
of the classroom...thereby effectively gamma matching the steel cage of
the school building. We could be heard many times the legal distance of
2x lambda x freq.

How Do ? - The IsoTrons Antennas Work So Well?


So well? The same way a shopping cart can work "so well".

In article . com,
"RHF" wrote:

For One and All,

Thank You "JP" for bring the IsoTron Antenna
website to my attention.

The IsoTron Antenna represents an interesting Antenna design
and build techniques for an compact Transmitting (and Receiving)
Antenna to be used in small Spaces and locations where there are
physical limits to work within. ~ RHF
http://groups.yahoo.com/group/Shortw...a/message/9031

IsoTron Antennas -by- Ralph Bilal (Bilal Co)
http://www.isotronantennas.com/index.htm
HF Antennas designed and built for {small} Spaces
Designed and Built-by Ralph Bilal (Bilal Co)

How Do ? - The IsoTrons Antennas Work So Well?
http://www.isotronantennas.com/isohow.htm
The IsoTron Antennas are Electrically Resonant
by using only two components - the Large Coil
in Series with the Capacitive Plates that are
the center {main components} of the Antennas.

IsoTron Antennas - Photos
http://www.isotronantennas.com/photos1.htm

IsoTron "AM Broadcast Band" Antenna
http://www.isotronantennas.com/ambroad1.htm

Reference Message -by- "Jack Painter" *t
http://groups.yahoo.com/group/Shortw...a/message/9019
.
.
and now you know - iane ~ RHF
.
All are WELCOME and "Invited to Join" the
Shortwave Listener (SWL) Antenna eGroup on YAHOO !
http://groups.yahoo.com/group/Shortwave-SWL-Antenna/
SWL ANTENNAS GROUP = http://tinyurl.com/an6tw
.
Some Say: On A Clear Day You Can See Forever.
I Believe : On A Clear Night You Can Hear Forever
. . . and Beyond , , , The BEYOND ! ! !
With a Shortwave Listening Antenna of your own making.
"If You Build It {SWL Antenna} You Will Hear Them !"
http://groups.yahoo.com/group/Shortwave-SWL-Antenna/
SHORTWAVE ANTENNA FORUM = http://tinyurl.com/an6tw

This is not a new idea to use reactive components as part of the
antenna to resonate it at an physical size much smaller than what would
ordinarily be needed. This concept is used in many designs usually to
normalize the antenna impedance to around 50 ohms so it accepts the
transmit energy.

There has been research in the area of reduced physical size antennas
on other designs that have shown similar radiation characteristics to
full size antennas so on the transmit side it looks like a promising
concept.

The antenna designs on this page are extremely reduced and I don't
believe the performance claims. The research I have seen that is
believable is a physical reduction of about one third on transmit.

However, on receive physical size relates to capture area and smaller
antennas, even resonant ones, will not pick up as much energy as a full
size antenna. Here small physical size is generally made up for with
amplification.

One of the characteristics of an efficient antenna is its ability to
couple to the environment around it. Here on the surface of the earth
the dielectric is air and since electromagnetic radiation travels at a
certain speed in air that means there is a specific relationship
between physical size of electrical elements and electrical length
where the electrical length determines where the antenna will resonate.

Using reactive components as part of the antenna to cause a "break" in
this physical length to electrical length relationship results in the
antenna not being as well coupled to the space around it and so it is
less efficient.

--
Telamon
Ventura, California

"RHF" wrote in message
oups.com...
Dale [W4OP],
"The consensus is that the coax is the actual radiator;
the "antenna" is the matching network.
The longer the coax, the better it works. "

So the IsoTron Antenna :
Efffectively puts the Antenna Tuner at the Far-End of the
Coax Cable and makes the Coax Cable the Antenna
Element {Radiator} between the Transmitter and the
IsoTron {Resonant Load = Terminator} Antenna.

interesting idea - iane ~ RHF
.
.
.It would be if the designer had intended that. The problem is that you
now have a radiator inside the shack and an antenna whose characteristics
are a function of how the "feedline" is deployed.

Dale .
.

I could probally do better than an IsoTron by wrapping some wire around
my aluminum ladder.
cuhulin

In article .com,
"RHF" wrote:

Dale [W4OP], "The consensus is that the coax is the actual radiator;
the "antenna" is the matching network. The longer the coax, the
better it works. "

So the IsoTron Antenna : Efffectively puts the Antenna Tuner at the
Far-End of the Coax Cable and makes the Coax Cable the Antenna
Element {Radiator} between the Transmitter and the IsoTron {Resonant
Load = Terminator} Antenna.

interesting idea - iane ~ RHF

It is more than an interesting idea, it is what is happening.
Additionally the tower is a radiator along with the coax. The tower
probably radiates more than the coax. The "antenna" is really a matching
network to the tower.

--
Telamon
Ventura, California

What is ''happenin'' is just now when I went to my bathroom ''library''
and I thumbed through the last half of my snail mail delivery May issue
of Popular Mechanics magazine.
cuhulin

Dale [W4OP],

Routing of the Coax Cable should always be a
consideration in Planning and Laying-Out any
Antenna System - Especially when the Coax
is the Prime Radiator ;-} ~ RHF

Cuhulin,

Better yet, take your 24 Foot Extension Ladder
and separate the two pieces.

Lay the two sections of the Ladder on the ground
in a straight-line with the inner-ends about a foot
apart and use a Plastic Tote Box (4) at the end of
each piece to prop them up off the ground.

Connect a piece of Ladder Line for the feed-in-line
to the inner-ends.

You have a Ladder-Ladder Dipole Antenna that is
just above the ground.

Should work pretty good around 9.75 MHz.

iane ~ RHF