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-   -   Curtain Quad - Real gain or antenna snake oil? (https://www.radiobanter.com/antenna/168101-curtain-quad-real-gain-antenna-snake-oil.html)

Jeff Liebermann[_2_] July 17th 11 05:14 AM

Curtain Quad - Real gain or antenna snake oil?
 
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

Jeff Liebermann[_2_] July 18th 11 09:47 PM

Curtain Quad - Real gain or antenna snake oil?
 
On Mon, 18 Jul 2011 14:12:43 -0500, John S
wrote:

Sorry Jeff, I need to try again,
Either I'm doing a very poor job of explaining my lack of understanding
or maybe we are looking at two different pages.
If you look here;
http://home.comcast.net/~ross_anders...MHzAntenna.htm
you will see the FENCE is used as the ANTENNA ELEMENTS and aluminum foil
used as the reflector.
But the fence loops seem to me to be the same size for both 1296Mhz
and 2.4Ghz antenna.
Mikek


I concur with your observation, Mikek. It may be that Jeff has looked
only at the first listed reflector which was identical to the antenna
itself.

Both the 1296 and 2.4gHz antennas use the same fencing material.
John - KD5YI


Nope, my mistake. Brain damage and assumption on my part.

http://home.comcast.net/~ross_anderson/CurtainQuadFigure11.htm
http://home.comcast.net/~ross_anderson/2400MHzAntenna.htm

I didn't use the recommended fencing material. Instead, I made mine
from some #16 awg solid copper wire, soldering the junctions together.
When I built the 2.4GHz version, I scaled it from the 1.2GHz
dimension, resulting in NOT using the 2x3" fencing material. I then
built it without looking at the original article again. I'll dig
deeper and see if I can find the 2.4GHz antenna and design data.

That brings me back to the original question, which is how can both
antennas be made from the same 2x3" fencing material. I'm not sure
what's happening because the drawings are not fully dimensioned. I
also just noticed that the grid paper shown do not match the
dimensions listed in the NEC deck. Logic (and guesswork) would
suggest that if the 2x3" mesh was used for 2.4GHz, then every other
wire could be used on 1.2GHz, forming a 2x6" mesh. However, I can't
tell from the dimensioning. I'll try to transplant the dimensions to
a common drawing, and see if it can be decoded.

Gone to do some chain sawing. More if I survive.

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


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