Difference between revisions of "Ham Radio Antenna Design Notes"

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Precision in element length becomes more significant at higher frequency
 
Precision in element length becomes more significant at higher frequency
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Understand how capacity hats impact resonance
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== Impedance Dipole vs Inverted V ==
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A dipole in free space should have about 72 ohms of input impedance.  As you move the poles down to form and inverted V the impedance lowers.

Revision as of 21:53, 29 July 2017

Considerations in Design

resonance / swr

Q

Impedance

Common Mode Current

Velocity Factor

Math

492 / Freq in MHz

1005 / MHz

Talking Points of Experience

Loading coil to simulate length, but inefficient and generates heat, doesn't handle high power well.

DC grounded antennas are ideal: prevents static build up on antenna

Precision in element length becomes more significant at higher frequency

Understand how capacity hats impact resonance

Impedance Dipole vs Inverted V

A dipole in free space should have about 72 ohms of input impedance. As you move the poles down to form and inverted V the impedance lowers.