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5/8 Wavelength Antenna Top Loading


New Member
When I was younger, I had a CB radio with a 5/8 wave base station antenna. The antenna had a capacitance hat on the top and a tapped coil on the bottom. I Know what the tapped coil is for, impedance matching. I'm not so sure about the capacitance hat. I've been reading up on top loading with capacitance hats with antennas that are less than a 1/4 wavelength and depending on the frequency and height may not even require a loading coil to achieve resonance. I learned that top loading with a capacitance hat, with respect to an antenna less than a 1/4 wavelength anyway, electrically lengthens the antenna like a loading coil would.

So does top loading a 5/8 wave antenna with a capacitance hat work the same way?

Can a capacitance hat electrically lengthen a physical 5/8 wave antenna to an electrical 3/4 wavelength to resonate it, then use a tapped coil to impedance match the remaining pure resistance at the feed point on the bottom?

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