I've posted a picture on alt.binaires.schematics.electronic
to an effort to help me get a better understanding of an antenna.
It is a 2.4Ghz antenna about 18" long
The driven element is a copper ribbon 0.2" wide by 0.032" thick.
The copper ribbon forms a loop about 2" wide by 0.625" tall.
The gap in the ribbon would be 0.020", but note; in the pictures
a moon shaped piece has been cut from both ends. I think this
moon cut effectively make the gap look larger.
The total coax length is 2.350", the shield a bit shorter at 2.08".
There are 4 toroids on the coax. These are under a piece of heat
shrink, so I have no idea what material they would be.
All element spacings are all equal and element lengths are within
..030" of each other. I think they were designed to be the same but
manufacturing tolerances made the differences. The reflector is longer.
So now what can the group tell me about;
Driven element impedance
the gap
coax length impedance transformation
the 4 toroids
Thanks for the help, if you need any other details let me know.
Mike