T2FD Antenna Experts Please Chime In

tom k in L.A.

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Mar 16, 2008, 3:01:14 PM3/16/08

to

So I'm moving from a house in LA to an apartment in NYC.

Right now I'm using a Sony AN-LP1 suction cupped to the window in NYC
and getting good reception.

If I place my RF Systems T2FD partially rolled up (too big to unroll
all the way) across the window sill, will I get even better
reception? I'm wondering if the T2FD will be better than the AN-LP1.
The T2FD is a total RFI killer and really opened up the shortwave band
to me at my house in LA. Wondering if it might do the same in NYC,
but it would be partially unrolled across the window sill. Thanks
all.

tk

dxAce

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Mar 16, 2008, 4:29:28 PM3/16/08

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I've made and used a couple of T2FD's and found them lacking. Having said that,
it seems the way you want to use it you'd essentialy be using a wad of wire. Try
it and see how it works.

dxAce
Michigan
USA

tom k in L.A.

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Mar 16, 2008, 5:49:48 PM3/16/08

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I had great luck with mounting it outdoors here in LA. Best antenna I
ever used for eliminating RFI in an urban environment. That's why the
US Consulate in Jerusalem uses it! See here: http://www.simonmason.karoo.net/page498.htm

Just wondering if it will work well in the window.

dxAce

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Mar 16, 2008, 5:53:28 PM3/16/08

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"tom k in L.A." wrote:

Well, like I said, try it and see how it works. That's the only way you'll find out.

Telamon

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Mar 16, 2008, 5:59:27 PM3/16/08

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In article
<54f91aa1-37a0-4191...@s13g2000prd.googlegroups.com>,

You just found out that a closed loop antenna will work better in a
locally noisy environment.

What did you use for a BALUN?

What are the dimensions of the antenna you built?

--
Telamon
Ventura, California

RHF

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Mar 16, 2008, 6:10:43 PM3/16/08

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On Mar 16, 2:53 pm, dxAce <dx...@milestones.com> wrote:
> "tom k in L.A." wrote:
>
> > I had great luck with mounting it outdoors here in LA. Best antenna I
> > ever used for eliminating RFI in an urban environment. That's why the
> > US Consulate in Jerusalem uses it! See here:http://www.simonmason.karoo.net/page498.htm
>
> > Just wondering if it will work well in the window.
>

- Well, like I said, try it and see how it works.
- That's the only way you'll find out.

Good Advise DX Ace,

The old expression goes : Seeing Is Believing.

-wrt- Radio : Hearing Is Believing.

And ultimately until you have tried it for yourself : You really
don't know what's best for you in your unique RF Environment.

~ RHF
.

tom k in L.A.

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Mar 16, 2008, 6:27:32 PM3/16/08

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Telamon I bought it from Universal Radio it's made by RF Systems and
has an integrated balun. Awesome antenna.

If this antenna is too unruly on the window sill, I will sell it on
ebay and you all can take a crack at it. Auction will include the
antenna plus a 100 foot coax run as well as a shorter 25 foot coax
run, both with terminations.

RHF

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Mar 16, 2008, 6:32:42 PM3/16/08

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On Mar 16, 2:59 pm, Telamon
<telamon_spamshi...@pacbell.net.is.invalid> wrote:
> In article
> <54f91aa1-37a0-4191-8bb4-4796d57ee...@s13g2000prd.googlegroups.com>,

> "tom k in L.A." <toma...@gmail.com> wrote:
>
> > I had great luck with mounting it outdoors here in LA. Best antenna I
> > ever used for eliminating RFI in an urban environment. That's why the
> > US Consulate in Jerusalem uses it! See here:
> >http://www.simonmason.karoo.net/page498.htm
>
> > Just wondering if it will work well in the window.
>

- You just found out that a closed loop antenna
- will work better in a locally noisy environment.

Telamon - A 'real' Winning Friends and
Influencing People Answer - NOT !

- What did you use for a BALUN?

Teli - A good 'tell-me-more' dialog opener. :o)

- What are the dimensions of the antenna you built?

Teli - Also good 'tell-me-more' dialog follow-up. :o)

-
- --
- Telamon
- Ventura, California
-

Telamon,

Please Note - The Original Poster that started this Message Thread
Tom-K-in-LA stated he was using an RF Systems T2FD Antenna
which is a ready-made Shortwave Listening (SWL) Antenna.

RF Systems T2FD Receive Antenna : Covering 3 MHz ~ 35 MHz
http://www.rf-systems.nl/T2FD.html
http://www.universal-radio.com/catalog/sw_ant/0562.html
* Special Frequency-Compensating 11:1 Transformer
* 45 Feet (15 Meters) in Length {90+ Feet of Wire in the Air}

T2FD -- The Forgotten Antenna -by- Guy Atkins
http://www.hard-core-dx.com/nordicdx/antenna/wire/t2fd.html
T2FD -means- Terminated Tilted (T2) + Folded Dipole (FD)

Terminated Tilted Folded Dipole Shortwave Antenna (T2FD)
http://www.johncon.com/john/T2fd/
-by- John Conover

More T2FD Info - http://en.wikipedia.org/wiki/T2FD_Antenna

hope this helps - iane ~ RHF
.

Telamon

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Mar 16, 2008, 7:32:39 PM3/16/08

to

In article
<4540f877-95b9-486d...@s37g2000prg.googlegroups.com>,

That is a good antenna design for receive. It's OK for transmit but
depending on circumstances that resistor dissipates some power.

I'm not quite sure what you mean about the window sill as this is a big
antenna. As with all antennas the higher up you can get it the better it
will receive distant signals.

--
Telamon
Ventura, California

Telamon

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Mar 16, 2008, 7:38:12 PM3/16/08

to

In article
<8e7ed34d-f4eb-4d3b...@u10g2000prn.googlegroups.com>,
RHF <rhf-new...@pacbell.net> wrote:

> On Mar 16, 2:59 pm, Telamon
> <telamon_spamshi...@pacbell.net.is.invalid> wrote:
> > In article
> > <54f91aa1-37a0-4191-8bb4-4796d57ee...@s13g2000prd.googlegroups.com>,
> > "tom k in L.A." <toma...@gmail.com> wrote:
> >
> > > I had great luck with mounting it outdoors here in LA. Best antenna I
> > > ever used for eliminating RFI in an urban environment. That's why the
> > > US Consulate in Jerusalem uses it! See here:
> > >http://www.simonmason.karoo.net/page498.htm
> >
> > > Just wondering if it will work well in the window.
> >
> - You just found out that a closed loop antenna
> - will work better in a locally noisy environment.
>
> Telamon - A 'real' Winning Friends and
> Influencing People Answer - NOT !

Get lost Trolling idiot. Nobody asked you.

--
Telamon
Ventura, California

Telamon

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Mar 16, 2008, 7:38:22 PM3/16/08

to

In article
<9ef51956-b590-46f3...@i29g2000prf.googlegroups.com>,

The moron responds thusly RHF <rhf-new...@pacbell.net> wrote:

> On Mar 16, 2:53 pm, dxAce <dx...@milestones.com> wrote:
> > "tom k in L.A." wrote:
> >
> > > I had great luck with mounting it outdoors here in LA. Best antenna I
> > > ever used for eliminating RFI in an urban environment. That's why the
> > > US Consulate in Jerusalem uses it! See
> > > here:http://www.simonmason.karoo.net/page498.htm
> >
> > > Just wondering if it will work well in the window.
> >
> - Well, like I said, try it and see how it works.
> - That's the only way you'll find out.
>
> Good Advise DX Ace,
>
> The old expression goes : Seeing Is Believing.

I see a retard post.

> -wrt- Radio : Hearing Is Believing.

The voice of a retard.

> And ultimately until you have tried it for yourself : You really
> don't know what's best for you in your unique RF Environment.

Makes no difference to you. You could be hit hit over the head with 2X4
clue stick and it would not register.

--
Telamon
Ventura, California

RHF

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Mar 17, 2008, 5:12:18 AM3/17/08

to

Tom-K-in-LA,

First lets take a look at the two Shortwave Listener Antennas :
{ Lets Reason Things Out form a Practical Point of View. }

Situation : Sony AN-LP1 Active Loop Shortwave Antenna
-versus- RF Systems T2FD {Passive} Shortwave Antenna
that is rolled-up and placed on the same Window as the
Sony had been located in an Apartment.

The Sony AN-LP1 Active Loop Shortwave Antenna is an
http://www.universal-radio.com/catalog/sw_ant/3676.html
"E" Probe type of Antenna using a relatively small size
Antenna Element* and an Impedance Matching Amplifier
Circuit to 'connect' the Antenna Element with the surrounding
RF Environment and Amplify and Match that RF Signal from
the Antenna Element to the Coax Cable feed-in-line going
to the Radio / Receiver.
* Note that the Sony AN-LP1 Active Loop Shortwave Antenna
has a very small Loop Antenna Element which is about 19"
Diameter when open. This means the Loop Antenna Element
has a very small Signal Capture Area which creates very small
levels of RF Signals; and these tiny RF Signals must be
Amplified for use with a Shortwave Radio /Receiver.
+ Antenna Element : 19" x 3.14 = 60 Inches ~ Five Feet
+ Signal Capture Area : (19"/2)^2 x 3.14 = 283.4 Square
Inches ~ Two Square Feet

The RF Systems T2FD is a Passive (Non-Amplified)
http://www.rf-systems.nl/pdf/t2fd.pdf
Shortwave Antenna that measures about 45 Feet Long
Tip-to-Tip and about 18 Inches (1.5 Feet) Wide Top-Wire
to Bottom-Wire; and has about 93 Feet of Wire up in the
Air with a Signal Capture Area of 45 x 1.5 = 67.5 Sq. Ft.
The T2FD Antenna is relatively large and it's Signal Capture
Area is relatively Big -with-respect-to- the Sony AN-LP1;
the T2FD Antenna produces a relatively strong level of
RF Signals; and the T2FD Antenna does not require an
Amplifier to provide good RF Signal Levels to a Radio /
Receiver. -P R O V I D E D- That the T2FD Antenna is
Stretched-Out-Fully and Up-in-the-Air.

Tom-K - Your situation has the T2FD Antenna Rolled-Up*
placed in a Window; with may be a Signal Capture Area
of about 3-Feet-by-3-Feet = 9 Square Feet. The Wires
of the T2FD Antenna are not stretched-out froming a Loop
-but- Rolled-Up froming four Coils.
* THIS AIN'T A T2FD - It is a HodgePodge of Crossed Wires
-aka- MishMash of Wires with crossed RF Signal Paths.
.
- - - - Original Message Posted with Comments - - - -
.
On Mar 16, 12:01 pm, "tom k in L.A." <toma...@gmail.com> wrote:
-
- So I'm moving from a house in LA to an apartment in NYC.
-
- Right now I'm using a Sony AN-LP1 suction cupped
- to the window in NYC and getting good reception.

Take the time to 'find' the best Window in your Apartment
that the Sony AN-LP1 Active Loop Shortwave Antenna
works in : Best Signals and Lowest Noise.

- If I place my RF Systems T2FD partially rolled up
- (too big to unroll all the way) across the window sill,
- will I get even better reception?

IMHO - Maybe -but- Most likely NO.

Question ? Is your Window Sill and Window Frame Metal ?
or Painted / Plastic / Wood Covered Metal ? :
1 - Then keep the Sony AN-LP1 Active Loop Shortwave
Antenna centered in the Window and away from the Metal.
2 - Then keep the Wires of the RF Systems T2FD Antenna
at least 3~6 Inches away from the Metal.

- I'm wondering if the T2FD will be better than the AN-LP1.

IMHO - Maybe -but- Most likely NO.

- The T2FD is a total RFI killer and really opened up
- the shortwave band to me at my house in LA.

Good that is what it is supposed to do : When it is
Fully Stretched-Out-and Up-in-the-Air and Tilted at
30 Degrees. {It Worked A-OK :o}

- Wondering if it might do the same in NYC,
- but it would be partially unrolled across the window sill.

IMHO - Sorry to say : Most likely NO.

First - Nine (9) Square Feet of Signal Capture Area is a
Fraction (1/7th) of 68 Square Feet and you should
Not Expect the same RF Signal Levels.

Second - The Wire Antenna Element is no-longer a
physically shaped balanced Loop (O) -but- a jumble
of Crossed Wires and Signal Paths.

Third - The Wire Antenna Element is no-longer Out
In-the-Air and away from the Homes Envelope of
Man Made Noise : The Wire Antenna Element is
Inside the Appartment and within the Buildings
Envelope of Man Made Noise.

Result : Lower RF Signal Levels plus Higher RF Noise Levels.

- Thanks all.
- tk
-

tom-k - hope that his answer helps - iane ~ RHF {pomkia}
.
Shortwave Listener (SWL) Antennas Group => http://tinyurl.com/ogvcf
GoTo => http://groups.yahoo.com/group/Shortwave-SWL-Antenna/
.
RHF's Standard "Shortwave Listener (SWL) Antennas Group"
For a Reduced Message Signature Line Reference Message
http://groups.google.com/group/rec.radio.shortwave/msg/411dac3b4a1798e0
.

joe

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Mar 17, 2008, 8:36:09 AM3/17/08

to

RHF wrote:

> Tom-K-in-LA,
>
> First lets take a look at the two Shortwave Listener Antennas :
> { Lets Reason Things Out form a Practical Point of View. }
>
> Situation : Sony AN-LP1 Active Loop Shortwave Antenna
> -versus- RF Systems T2FD {Passive} Shortwave Antenna
> that is rolled-up and placed on the same Window as the
> Sony had been located in an Apartment.
>
> The Sony AN-LP1 Active Loop Shortwave Antenna is an
> http://www.universal-radio.com/catalog/sw_ant/3676.html
> "E" Probe type of Antenna using a relatively small size
> Antenna Element* and an Impedance Matching Amplifier

A loop antenna is NOT an e-probe.

Rest of nonsense deleted.

RHF

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Mar 17, 2008, 4:07:16 PM3/17/08

to

On Mar 17, 5:36 am, joe <x...@not.here> wrote:
- - RHF -wrote-
- - Tom-K-in-LA,
- -
- - First lets take a look at the two Shortwave Listener Antennas :
- - { Lets Reason Things Out form a Practical Point of View. }
- -
- - Situation : Sony AN-LP1 Active Loop Shortwave Antenna
- - -versus- RF Systems T2FD {Passive} Shortwave Antenna
- - that is rolled-up and placed on the same Window as the
- - Sony had been located in an Apartment.
- -
- - The Sony AN-LP1 Active Loop Shortwave Antenna is an
- - http://www.universal-radio.com/catalog/sw_ant/3676.html
- - "E" Probe type of Antenna using a relatively small size
- - Antenna Element* and an Impedance Matching Amplifier
- -

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
-
So under this 'screen-name' of "Joe" you have a total of
Five (5) posts here since March 4 2008. Which leads
me to believe that you are a Sock-Puppet for some one
else who frequents the RRS Newsgroup.
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

=WRT= T2FD Antenna Experts Please Chime In
http://groups.google.com/group/rec.radio.shortwave/msg/a0e82457c7f6094c

Joe -wrote- "A loop antenna is NOT an e-probe."

Joe,

The Electric-Field "E" Probe View-Point
"It can be rigged as a VERY directional E probe"
http://www.radiocom.net/

The Magnetic-Field "H" Probe View-Point
"The Broadband Loop is balanced antenna and responds
primarily to the magnetic-field, this ensures high rejection
of nearby electric-fields. The intensity of the electric-field
is usually higher than the magnetic-field when an antenna
is close to interference sources"
http://brneurosci.org/radio-misc.html

"The Loop antenna responds primarily to the Magnetic-Field
and rejects locally radiated Electric-Field noise providing far
lower noise reception than active whip/dipole antennas."
http://brneurosci.org/radio-misc.html

1 - Either way the Single Turn Loop Antenna Element
that is a small Fraction of a Wave-Length Long is a
"Probe" type of Antenna.

2 - When that Loop Antenna Element is 'connected' to
an Amplifier {Active} placed directly at the Element; and
that Amplifier is 'connected' to a Coax Cable feed-in-line :
The Resulting Antenna is an Impedance Matched and
Amplified "Probe" type of Antenna.

3 - Sony AN-LP1 Portable Active Antenna could be
called a Narrow-Banded {Un-Tuned} Loop Antenna.
http://cgi.ebay.com/_W0QQitemZ140214066985
The Control Box is equipped with a Frequency Band
{Narrow Range} Selection Knob : ~4 MHz, ~5 MHz,
~6 MHz, ~7 MHz, ~10 MHz, ~12 MHz, ~14 MHz,
~16 MHz, and ~20 MHz This Knob {Switch} allows
the Selection of any of these Bands which cover the
major Shortwave Radio Broadcast Bands. It generally
the Sony AN-LP1 Amplifies "All" the Frequencies
within these Narrow Bands and Attenuates the
Frequencies that are out of the specific Band.
Note - There is NO Fine-Tuning within the Bands.
http://www.universal-radio.com/catalog/sw_ant/3676pre.jpg

That-Something-Extra -Read- Joe Carr's Radio Tech-Notes
"Small Loop Antennas" -by- Joseph J. Carr
http://www.dxing.com/tnotes/tnote08.pdf

=WRT= T2FD Antenna Experts Please Chime In
http://groups.google.com/group/rec.radio.shortwave/msg/a0e82457c7f6094c

Joe -wrote- "Rest of nonsense deleted." - Nonsense* ?