Hello fellow shortwave listeners !

More info to make a T2FD yourself, like I did mine, please have a
look at:

http://members.home.nl/rita.kees/t2fdmake.html


I hope you can appreciate it and use it for your practice.


I will be glad to answer your questions.

73/cheers

Kees

Kees wrote:
Hello fellow shortwave listeners !

More info to make a T2FD yourself, like I did mine, please have a
look at:

http://members.home.nl/rita.kees/t2fdmake.html


I hope you can appreciate it and use it for your practice.


I will be glad to answer your questions.

73/cheers

Kees




http://members.home.nl/rita.kees/t2fd1.gif

I found that my garage is WAY to far away to use this setup.

Following the formula, I took an average frequency of 10 Megahertz. I
divided into 100, as per the formula. I got an antenna length of
(100ft/10,000,000) = 1 X 10^-5 feet, or 0.00012 inches.

I then thought that this just couldn't be right. I redid it using Meters
instead of feet and arrived at 0.00001 meters length. MUCH BETTER! The
problem now is that the store only sells full length rolls of wire.
Where can I mail order a smaller chunk? Can they just wrap the postage
stamp around it to save shipping costs?

Being ever on the watch for cheap alternatives, what is a cheap way of
relocating the far end antenna support?

I don't want to pay to have the garage moved.

Any insights appreciated.



mike












--
__ __ __ __ __ __ __ __
/ /\ / /\ / /\ / /\ / /\ / /\ / /\ / /
/ /\ \/ /\ \/ /\ \/ /
/_/ \/_/ \/_/ \/_/ \/_/ \/_/ \/_/ \/_/

..let the cat out to reply..

©Densa International
'Think tanks cleaned cheap'

"Kees" wrote in message
...
Hello fellow shortwave listeners !

More info to make a T2FD yourself, like I did mine, please have a
look at:

http://members.home.nl/rita.kees/t2fdmake.html

I hope you can appreciate it and use it for your practice.

I will be glad to answer your questions.

73/cheers

Kees


The Tilted Terminated Folded Dipole ("T2FD") is a broadband folded dipole
antenna design that provides a relatively
stable feed point impedance over about a five to one frequency range. The
antenna
length in meters is approximately 100 divided by the lowest desired
operating
frequency in megahertz. The upper element of the folded dipole is opened in
the
center and a non-inductive terminating resistor of around 350-400 ohms is
inserted.
The bottom element is fed in the center through a 6-to-1 balun for a good
match to
50 ohm feed line.

The antenna is not as efficient as a matched half wave dipole at any
specific
frequency, but it also does not require an antenna tuner for operation,
making it
easy to use. The loss of receiving efficiency is not generally noticeable
in the high frequency range (2-30 MHz), amounting to less than 6 db (one
standard
S-unit) during extensive on-the-air testing.

Here is additional information on the T2FD antenna.

Barker & Williamson actually applied for a US patent (US Patent #4423423)
for their specific T2FD antenna design.
http://www.fact-index.com/t/t2/t2fd_antenna.html

While this may be acceptable for SWL operation, the resistor does not have
sufficient wattage for
any station attempting to use this for a transmitting antenna.
http://www.tuberadio.com/tfd.html

http://www.universal-radio.com/catalog/sw_ant/0562.html


w9gb

m II wrote:
Kees wrote:

Hello fellow shortwave listeners !

More info to make a T2FD yourself, like I did mine, please have a
look at:

http://members.home.nl/rita.kees/t2fdmake.html


I hope you can appreciate it and use it for your practice.


I will be glad to answer your questions.

73/cheers

Kees




http://members.home.nl/rita.kees/t2fd1.gif

I found that my garage is WAY to far away to use this setup.

Following the formula, I took an average frequency of 10 Megahertz. I
divided into 100, as per the formula. I got an antenna length of
(100ft/10,000,000) = 1 X 10^-5 feet, or 0.00012 inches.

I then thought that this just couldn't be right. I redid it using Meters
instead of feet and arrived at 0.00001 meters length. MUCH BETTER! The
problem now is that the store only sells full length rolls of wire.
Where can I mail order a smaller chunk? Can they just wrap the postage
stamp around it to save shipping costs?

Being ever on the watch for cheap alternatives, what is a cheap way of
relocating the far end antenna support?

I don't want to pay to have the garage moved.

Any insights appreciated.



mike


In physics always use meters, kilograms, joules and not inches, pounds
or horsepower

Hans

Hans wrote:

In physics always use meters, kilograms, joules and not inches, pounds
or horsepower


Of course. Sorry about my retrograde calculations, however, the numbers
provided on the site need to be clarified, as they don't work either in
either method.

An example at the bottom of the page using the proper units would be in
order. The confusion is what caused me to post to begin with.

100 anything divided by millions of other units is bound to cause very
small numbers and in this case very small numbers give birds no place to
perch.



mike

= = = "G.Beat" wrote in message
= = = news:UdtBc.152030$Ly.30888@attbi_s01...
"Kees" wrote in message
...
Hello fellow shortwave listeners !

More info to make a T2FD yourself, like I did mine, please have a
look at:

http://members.home.nl/rita.kees/t2fdmake.html

I hope you can appreciate it and use it for your practice.

I will be glad to answer your questions.

73/cheers

Kees


The Tilted Terminated Folded Dipole ("T2FD") is a broadband folded dipole
antenna design that provides a relatively
stable feed point impedance over about a five to one frequency range. The
antenna
length in meters is approximately 100 divided by the lowest desired
operating
frequency in megahertz. The upper element of the folded dipole is opened in
the
center and a non-inductive terminating resistor of around 350-400 ohms is
inserted.
The bottom element is fed in the center through a 6-to-1 balun for a good
match to
50 ohm feed line.

The antenna is not as efficient as a matched half wave dipole at any
specific
frequency, but it also does not require an antenna tuner for operation,
making it
easy to use. The loss of receiving efficiency is not generally noticeable
in the high frequency range (2-30 MHz), amounting to less than 6 db (one
standard
S-unit) during extensive on-the-air testing.

Here is additional information on the T2FD antenna.

Barker & Williamson actually applied for a US patent (US Patent #4423423)
for their specific T2FD antenna design.
http://www.fact-index.com/t/t2/t2fd_antenna.html

W9GB,

B&W makes two general statements about the T2FD:

* For example, an {T2FD} Antenna for the lower portion of
Shortwave (3 - 18 MHz) will be roughly 33m (110 feet) long,
with conductors spaced 1m (3.3 feet).
[With a Top End mounted about 60 Feet High at 30 Degrees.]

* In order to cover the higher portion of Shortwave (5 - 30 MHz),
this {T2FD} Antenna will be roughly 20m (66 feet) long,
with a spacing of 60 cm (24 inches).
[With a Top End mounted about 40 Feet High at 30 Degrees.]

Build one size or the other = No Formula Required.

Read: T2FD Antenna - WOW ! ! ! {One SWL's Experiance}
http://groups.yahoo.com/group/Shortw...na/message/293

iane ~ RHF
..
..

While this may be acceptable for SWL operation, the resistor does not have
sufficient wattage for
any station attempting to use this for a transmitting antenna.
http://www.tuberadio.com/tfd.html

http://www.universal-radio.com/catalog/sw_ant/0562.html


w9gb
..

The fact that we get widely varying reports about the performance of the
T2FD antenna suggests that an equally-long dipole would give good results
across the frequency spectrum if used with an antenna tuner. What the
T2FD really buys you is the ability to avoid an antenna tuner.

There is an amateur antenna out there consisting of an 80-meter dipole
(I mean one that is a half wave at 80 meters, not one physically 80 meters
long) fed with about 100 feet of 450 ohm ladder line. It turns out that
100 feet of line is within about 10% of the idea length to match the
antenna to 50 ohms on all amateur bands. One design of this antenna uses
a tuner to correct for the mismatch, while another uses various lengths
of 450 ohm line added to the feedline to achieve a match.
--

jhhaynes at earthlink dot net

"Kees" wrote in message
...
Hello fellow shortwave listeners !

More info to make a T2FD yourself, like I did mine, please have a
look at:

http://members.home.nl/rita.kees/t2fdmake.html


I hope you can appreciate it and use it for your practice.


I will be glad to answer your questions.

73/cheers

Kees


I have no idea how well the antenna works, but the method of connecting the
reisistor is very complicated. May I suggest:

Connect the two wires to a normal dog-bone insulator, and solder the
resistor across the insulator to the two wires. Insulate if you wish. For
receive only, a 1/2 W resistor is as good, or better.

Tam/WB2TT

I have no idea how well the antenna works, but the method of connecting the
reisistor is very complicated. May I suggest:

Hi Tam, For receive only, a doublet antenna, as high as possible, with 50
ohm,or 75, or 300 ohm feedline will work well. I have no idea why people want
to complicate receive antennas with resistors. Do you?
73 Gary N4AST

"JGBOYLES" wrote in message
...
I have no idea how well the antenna works, but the method of connecting
the
reisistor is very complicated. May I suggest:

Hi Tam, For receive only, a doublet antenna, as high as possible, with 50
ohm,or 75, or 300 ohm feedline will work well. I have no idea why people
want
to complicate receive antennas with resistors. Do you?
73 Gary N4AST

Hi Gary,
I use my 75 m antenna, which tops out at 70 feet for SWL listening. For 99%
of SWL listeners the limiting things are the poor IF filtering and overload
prone front ends. Also, I dont think you see a noise blanker in a sub $300
radio.

Tam