art wrote:
Gentlemen
In constructing "slow wave" antennas for top band I am finding that a
wavelength in equilibrium is a bit longer than expected.
As I am using large diameter formers for circular radiation I suspect
the reduction in number of turns is the reason.
Does anybody know of a turns versus length graph has been made for
this phenomina and where I could find it?
At present I start with scaling up a Tesla coil as a starting point
but that is becomming somewhat laborious after winding a few antennas.
( I will be placing a photo of my antenna on my page in a few days)
Here you go, Art. Equation 32 and Fig. 1 should be within
10% of what you need assuming your device meets the test
equation boundaries given between Equation 31 and Equation 32.
http://www.ttr.com/TELSIKS2001-MASTER-1.pdf
--
73, Cecil
http://www.w5dxp.com