I have a small, low power (50 mw) wireless camera that
transmits on 1.2 Ghz. Current range with a stub antenna
is about 200 feet, line of sight.

I could spend about $100 buying a commrecial loop yagi
for 1.2 Ghz, but I'd rather make something myself.
Any cantenna type designs for 1.2 Ghz?
I don't see any on the web, and I'm not sure how to scale
the 2.4 Ghz design for 1.2 Ghz use.

Am generally be interested in amplifying antenna designs
(both omni and directional) that can be put together
inexpensively.

Thanks!

aw

On Sat, 08 Nov 2003 08:45:10 -0500, www.ttdown.com
wrote:
I don't see any on the web, and I'm not sure how to scale
the 2.4 Ghz design for 1.2 Ghz use.

Hi OM,

Scaling is simple. It means exactly what the descriptive term
implies. Multiply EVERY dimension of EVERY element by 2 (but only if
the frequencies are an order of 2, use other ratios as appropriate).
This does not include the connector which should be isolated from the
antenna through a BalUn or Choke (if not already evident, or if this
is a new topic, research that separately, the connector is NOT an
antenna element).

73's
Richard Clark, KB7QHC

Thanks for your reply.
I'd still appreciate links to specific designs, if you or anyone
else has these...
It would be nice to know, for example, if someone has found
a pringles type can that has twice the radius and length of
the 2.4 Ghz design. Perhaps a German sausage co. uses
such cans for schnitzel...

I'm also not wedded to a cantenna type design.

If specific 1.2 Ghz design sites don't exist, how about a
reference to a good book on antenna design that won't
ignore 23 cm.

Thanks!

aw

-----------------------------------------------------------------------------


On Sat, 08 Nov 2003 19:34:27 GMT, Richard Clark
wrote:

On Sat, 08 Nov 2003 08:45:10 -0500, www.ttdown.com
wrote:
I don't see any on the web, and I'm not sure how to scale
the 2.4 Ghz design for 1.2 Ghz use.

Hi OM,

Scaling is simple. It means exactly what the descriptive term
implies. Multiply EVERY dimension of EVERY element by 2 (but only if
the frequencies are an order of 2, use other ratios as appropriate).
This does not include the connector which should be isolated from the
antenna through a BalUn or Choke (if not already evident, or if this
is a new topic, research that separately, the connector is NOT an
antenna element).

73's
Richard Clark, KB7QHC

Take a look here.
http://f5ad.free.fr/ANT-QSP_Descriptions_1200.htm

Or look here
The bandwith is about 20 MHz.That is enough for a fm video signal

http://www.sadona.com/news/ant_coaxcol.html

Thanks for the links!


---------------





On Sun, 09 Nov 2003 12:12:46 GMT, "Atlas" wrote:

Take a look here.
http://f5ad.free.fr/ANT-QSP_Descriptions_1200.htm

Or look here
The bandwith is about 20 MHz.That is enough for a fm video signal

http://www.sadona.com/news/ant_coaxcol.html