Why is copper better than steel for wire antenna?
Roy, W7EL wrote:
"Either you didn`t read the remainder of what I wrote, or I failed to
explain it clearly."
The fault was mine, not Roy`s. It is true that if you scale an antenna
for half the frequency by doubling its length without increasing
cross-section of the wire, its resistance increases. Resistance is
rho(l/a) where rho is the resistivity, l is the length of the wire, and
a is the area of the wire`s cross-section.
Roy noted that lowering frequency by half means a wire twice as long
which tends to double the wire`s resistance but skin effect increases
penetration of the wire at the lower frequency. This reduces resistance
by 1/sq.Rt.2. The same antenna using twice the length of the same wire
but at half the frequency thus will have 1.414 times the effective
resistance of the double frequency antenna.
Best regards, Richard Harrison, KB5WZI
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