Explanation of basic antenna theory.
Formula for length of dipole antenna 468/ MHz= Length(feet) of antenna
Height-- more than 1/4 wavelength above ground
450ohm Ladder Wire = Each 16 gauge conductor is formed by 19 strands of 29 gauge copper-clad steel wire, making the line strong enough for long runs between supports, such as the DXE-LL-INS. Actual impedance is a nominal 400 Ohms with a nominal velocity factor of 91%. --more suitable for 2m.
300ohm LadderWire = Each conductor is 18 gauge consisting of 19 strands of copper clad steel wire, resulting in a Velocity Factor of 0.88. ---more suitable for 70cm.
LadderLine---wikipedia
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