November 14th 09, 06:57 PM
posted to rec.radio.amateur.antenna,alt.internet.wireless,sci.electronics.design
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First recorded activity by RadioBanter: Jul 2006
Posts: 349
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Folded Dipole Calculator Help
"Tony Hwang" wrote in message
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amdx wrote:
Hi All,
I'm having a disagreement about the use of this folded dipole
calculator
impedance calculator.
http://www.k7mem.150m.com/Electronic...ed_dipole.html
We are using it to calculate the impedance of folded dipoles to drive a
yagi.
When entering data it asks for "Simple dipole feed impedance (ohms)"
Default is 72 ohms. This assumes a 1/2 wave dipole.
The fellow I'm disagreeing with say's,
"the reason that the variable in the calculator for the "dipole feed
impedance"
could be if you want to transform the z to something else, such as 50
ohms."
I don't even understand what he means.
I can only think of one reason to alter the 72 ohms, that would be if you
use a a different length folded dipole.
I'll readily admit the other fellow knows more about this than me, but
I need more convincing :-)
Can anyone explain this to me.
Thanks, Mike
Hi,
The eq. seems right. Folded dipole is basically a loop.
Usually we use 300 Ohm feeder.
Tony
VE6CGX
In what case would I alter the 72 ohms?
Mike
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