That's what I was trying to say, Couldn't say it right..Thanks
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Antenna Builders! Copper?
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Am guessing the difference is negligible or the antenna calculator programs would ask for the type and size of material being used.
Nope; chances are that the first decent wind that comes along, it will fold over (vertical antenna). Due primarily to its soft/lack of rigidity and heavier weight. Otherwise, all antennas would be using copper. It's not just because of the cost or conductivity of copper, it is because it just doesn't handle wind load very well.
The difference in length due to the difference in materials is very negligible. Even going from 12 gauge wire to half inch pipe is minimal. Measurable yes but minimal. As with any antenna start a bit long and trim.
Way back when, some hams down this way built 2m turnstiles for 2m ssb out of copper. Didn't see any real difference. But hey, knock yourself out. Go full bling in Gold....
So copper wire will be a different length than copper clad wire??
Do you have any references to back up this statement??
why is a steel whip 102"
and a half wave dipole just also happens to be 102" each leg, does not matter if it is made out of copper or stainless steel 1/4 wl is a 1/4 wl.
http://www.kwarc.org/ant-calc.html
Here is an online calculator try it for yourself.
try 27.195 just for shits and giggles
DIAMETER of the conductor not TYPE of conductor will make the electrical length a little smaller in some applications.
The calculator you provided does not take into consideration the type of material being used. I've never found one that does. But if there was one, we might see a tiny difference. Because, as Captain Kilowatt stated above:
"The difference in length due to the difference in materials is very negligible. Even going from 12 gauge wire to half inch pipe is minimal. Measurable yes but minimal."
So, apparently, RPC is correct in saying the type of conductor does make a difference. It just isn't much of one.
The type of material will make a difference in efficiency but it is so tiny as to be ignored. The difference comes in IR losses due do the difference in resistance of the material. A steel wire antenna will be less efficient than a copper one but the difference in signal is negligible.
I said 12 ga. COPPER wire versus COPPER pipe ie. the size of the conductor. See my post above regarding different materials.
They will be the same, The Rf won't "see" the center material. that's the point of putting the copper material on the outside of the steel/ Aluminum.
Increasing the diameter of the conductor will lower the resistance, and as a side effect, will increase bandwidth.
BTW: The calculator you linked to is a generic formula, that doesn't take certain factors into consideration. but, it certainly gets real close.
Using 28.195 , a 1/4 wl is not 102 inches, it is 103.26 inches, thats' almost a 2% difference.
Actually, there are different formulas, with different "K" factors based on the material (and its conductivity,.. not "electrical wavelength". there is a technical difference.)
Without going into all the theory, that's why different formulas exist.
more elaborate computerized programs do take construction material into consideration,usually by inputting the radiators impedance into the calculations.
On a short 1/4 wl CB antennas, it may only make a small difference (however, the percentage is still the same) , but, on larger Amateur antenna, it becomes significant factor.