On Tue, 28 Jun 2011 11:00:44 -0700 (PDT), Michael
wrote:

I was researching multi-element driven array antennas when I stumbled
across the web page below. It talks about a curtain quad antenna. Is
this proven antenna design or antenna snake oil?

http://home.comcast.net/~ross_anderson/CurtainQuad.htm

Very real. I built the 2.4Ghz version. It works, but is rather
large. Unless you have plenty of real estate and tall towers, this is
not an HF antenna.

His curtain quad calculations and NEC2 deck are at:
http://home.comcast.net/~ross_anderson/CurtainQuadFigure11.htm

There's also the Sterba Curtain
http://imageevent.com/holl_ands/notfortv/sterba;jsessionid=ldhsj5x2v1.penguin_s
Gray-Hoverman
http://imageevent.com/holl_ands/grayhoverman/hovermantype1
and other antennas
http://imageevent.com/holl_ands/chireix/chireixmesnyrefl
resembling a collection of quads. As long as you get the phasing
correct, almost any geometry will radiate and have gain.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

On 6/28/2011 1:38 PM, Jeff Liebermann wrote:
On Tue, 28 Jun 2011 11:00:44 -0700 (PDT), Michael
wrote:

I was researching multi-element driven array antennas when I stumbled
across the web page below. It talks about a curtain quad antenna. Is
this proven antenna design or antenna snake oil?

http://home.comcast.net/~ross_anderson/CurtainQuad.htm

Very real. I built the 2.4Ghz version. It works, but is rather
large. Unless you have plenty of real estate and tall towers, this is
not an HF antenna.


Hi Jeff,
Why didn't the loop sizes shrink, when the author went from 1296Mhz
to 2400Mhz. First thing I thought about was etching it on a PCB.
But then saw he built the higher freq antenna with the same loop
lengths.
Mikek



His curtain quad calculations and NEC2 deck are at:
http://home.comcast.net/~ross_anderson/CurtainQuadFigure11.htm

There's also the Sterba Curtain
http://imageevent.com/holl_ands/notfortv/sterba;jsessionid=ldhsj5x2v1.penguin_s
Gray-Hoverman
http://imageevent.com/holl_ands/grayhoverman/hovermantype1
and other antennas
http://imageevent.com/holl_ands/chireix/chireixmesnyrefl
resembling a collection of quads. As long as you get the phasing
correct, almost any geometry will radiate and have gain.

On Sat, 16 Jul 2011 12:43:16 -0500, amdx wrote:


Hi Jeff,
Why didn't the loop sizes shrink, when the author went from 1296Mhz
to 2400Mhz. First thing I thought about was etching it on a PCB.
But then saw he built the higher freq antenna with the same loop
lengths.
Mikek

I'm not quite sure what you mean. However, I have a guess(tm).

His curtain quad calculations and NEC2 deck are at:
http://home.comcast.net/~ross_anderson/CurtainQuadFigure11.htm

If you scroll down to the bottom of the NEC deck, you'll find the
line:
FR 0 1 0 0 1332 0 'simulation is at 1332 MHz
That's the operating frequency. Change it to 2442 MHz and you have a
2.4GHz antenna.

The element dimensions in the NEC deck are in wavelengths. This makes
it very easy to use a design on different frequency. In order to
obtain construction lengths, simply multiply each element length by
the free space wavelegth. For 2.4GHz, that's about 12.5cm.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

On 7/16/2011 5:50 PM, Jeff Liebermann wrote:
On Sat, 16 Jul 2011 12:43:16 -0500, wrote:


Hi Jeff,
Why didn't the loop sizes shrink, when the author went from 1296Mhz
to 2400Mhz. First thing I thought about was etching it on a PCB.
But then saw he built the higher freq antenna with the same loop
lengths.
Mikek

I'm not quite sure what you mean. However, I have a guess(tm).

His curtain quad calculations and NEC2 deck are at:
http://home.comcast.net/~ross_anderson/CurtainQuadFigure11.htm

If you scroll down to the bottom of the NEC deck, you'll find the
line:
FR 0 1 0 0 1332 0 'simulation is at 1332 MHz
That's the operating frequency. Change it to 2442 MHz and you have a
2.4GHz antenna.

The element dimensions in the NEC deck are in wavelengths. This makes
it very easy to use a design on different frequency. In order to
obtain construction lengths, simply multiply each element length by
the free space wavelegth. For 2.4GHz, that's about 12.5cm.

Ah.. I'm still confused, For the 1296 antenna he used 2" x 3" fence
material and then the same 2" x 3" for the 2.4Ghz antenna except for
wire diameter.
Mikek

On Sat, 16 Jul 2011 20:59:34 -0500, amdx wrote:

His curtain quad calculations and NEC2 deck are at:
http://home.comcast.net/~ross_anderson/CurtainQuadFigure11.htm

Ah.. I'm still confused, For the 1296 antenna he used 2" x 3" fence
material and then the same 2" x 3" for the 2.4Ghz antenna except for
wire diameter.
Mikek

That's just the reflector material. Quoting from the above URL:
"The antenna is constructed from 3 inch by 2 inch galvanized
welded wire fence. Wire radius is 0.039 inch."
The reflector is not sensitive to the wire spacing as long as it's
sufficiently small. You could use chicken wire, wire mesh, metal
window bug screening, a barbeque grill, etc for the reflector. I used
some gastly 1/4" galvanized wire mesh, covered with aluminum foil.
For 1.2Ghz, his relfector is 28x21 inches. For 2.4Ghz:
http://home.comcast.net/~ross_anderson/2400MHzAntenna.htm
he didn't mention the size of the reflector, but it would half the
size of the 1.2GHz reflector.





--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558