5/8 home brew question

[cjruger]

Should the wire that runs from the match ring to vertical base be calulated in the radiater length? It seems like it should be, it is not vertical though
Its at least a foot long and kinda runs horizontal maybe angled down a little to bottom of radiator.
Also while im at it, i only have 3 103" radials now with a 1:3 swr. Will adding the 4th help swr? And should it be longer? What is the formula? My radials are wire and are not perfect, they are tied off to tree braches and prob not all at the same angle. Im working in a tree

 

[Marconi]

Should the wire that runs from the match ring to vertical base be calculated in the radiater length? It seems like it should be, it is not vertical though
Its at least a foot long and kinda runs horizontal maybe angled down a little to bottom of radiator.
Also while im at it, i only have 3 103" radials now with a 1:3 swr. Will adding the 4th help swr? And should it be longer? What is the formula? My radials are wire and are not perfect, they are tied off to tree braches and prob not all at the same angle. Im working in a tree

CJ, radiation starts as soon as the confines of the coax shield and center conductor are broken, so that wire is probably radiating some, and the longer it is the more effect it has. IMO it likely figures into the overall length of the radiating elements.

If you're just building an antenna from scratch...the best way to do the dimensions is to tune it, as best you can. Then do you measurements and record them to help you duplicate the setup in the future.

An antenna length calculator is only going to get you close. If your wire is a foot long then it surely has some effect on the length and the match. The length of the coil is probably more important than the wire length however.

I don't know about a radial calculators, but radials are typically 1/4 wave at the frequency of choice. I can't tell much difference when I use 3 radials vs. 7 radials that I've tried on my antennas with 1/4 wave radiators. I know there is a difference, but I can't measure it, so I don't think it is worth the effort.

With your radials tied off in a tree, what do you do when the wind blows the limbs really hard, pray?

I don't find trees and antennas always compatible in many ways. The height should help, but again I just didn't see a big difference, and going in a tree can be a lot of trouble.

 

[W5LZ]

That wire you're talking about does radiate some but not appreciably. It's part of the impedance matching device so isn't used in calculating the resonant length of the antenna at all.
- 'Doc

 

[cjruger]

That wire you're talking about does radiate some but not appreciably. It's part of the impedance matching device so isn't used in calculating the resonant length of the antenna at all.
- 'Doc

thanks guys,
ya the tree is not ideal but its realy my only option and seems to be working quite well. yes the radials probably move in the wind but they are secured with paracord and are flexable so they always go back to being taught. i plan to move the antenna much higher when i get the time. this will complicat the radial system as now i am able to use my 12 ft step ladder to tie off the ends.