Antenna with multiple radiators

An antenna capable of radiating at a short wavelength and capable of radiating at a long wavelength that is longer than said short wavelength, comprising:

• an antenna whip with upper and lower conductor portions, said upper conductor portion forming a radiator capable of radiating at both said long wavelength and said short wavelength to form an upper longwave radiator and an upper shortwave radiator;
• said lower conductor portion includes a coil constructed to produce a 180° phase shift at said longer wavelength, said lower conductor portion also including a lower phase reversal device which produces 180° phase shift at said shorter wavelength but which does not produce a phase shift at said longer wavelength, said phase reversal device lying below said coil;
• said lower phase reversal device having a predetermined length and having a phase reversal point at its upper end, and the distance between said phase reversal point and a lower end of said coil being less than the length of said phase reversal device.

An antenna which transmits at a given short wavelength comprising:

• an antenna whip with a conductor having an upper portion forming two radiators that each radiates at said short wavelength, said conductor upper portion including a PRD (phase reversal device) with a shorted PRD end, and with an opposite open, or non-shorted end;
• said PRD includes a center conductor portion of said upper conductor and a conductive sleeve that surrounds said center conductor portion, said sleeve having opposite ends with an upper one of said sleeve ends directly engaged with said PRD conductor portion to form said shorted PRD end, and with a lower one of said sleeve ends being non-shorted to said conductor portion, the length of said sleeve being ¼ wavelength of said short wavelength to produce a 180° phase shift to keep said two radiators in phase.

In an antenna that is capable of radiating at a short wavelength and that is capable of radiating at a long wavelength that is longer than said short wavelength and that is nonresonant to said short wave, wherein said antenna includes an antenna conductor with a first portion that forms a radiator at said long wavelength and that forms two short radiators at said short wavelength that extend in opposite directions from a point that lies between said two short radiators, the improvement comprising:

• a phase reversal device that includes a conductive sleeve having a length of about one-quarter wave at said short wavelength and surrounding said antenna conductor with a space between them, said sleeve having a shorted end where said sleeve is connected to said antenna conductor, said sleeve having an opposite non-shorted end and said sleeve being free of connection to said antenna conductor except at said shorted end;
• said non-shorted end of said sleeve lying at said point that lies between said two short radiators.

An antenna that is capable of radiating at a short wavelength and that is capable of radiating at a long wavelength that is longer than and nonresonant to said short wavelength, comprising:

• an antenna whip which includes an antenna conductor having upper and lower portions;
• a phase reversal device lying along said whip and comprising a conductive sleeve that surrounds said antenna conductor lower portion, said sleeve having a lower end that is shorted to said antenna conductor;
• a machined metal mount member that has an axis and an upper portion forming said conductive sleeve of said phase reversal device, said mount member having a hole lying on said axis and extending below said sleeve, with said antenna conductor projecting into said hole and fixed in place thereat.