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Author Topic: Half wave antennas.... Are they "really" frequency-specific???  (Read 493 times)

Mike Monte

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Maybe I should know this.........
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Scott Holtzman

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Maybe I should know this.........
Yes, absolutely just like a speaker is tuned for a driver an antenna is cut to frequency.

Any mismatch will cause power to be reflected back to the transmitter. 


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Scott AKA "Skyking" Holtzman

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Scott Helmke

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Re: Half wave antennas.... Are they "really" frequency-specific???
« Reply #2 on: April 24, 2024, 01:31:15 PM »

The Shure ones, and probably other decent quality center-fed dipole antennas, aren't really tuned to a specific single frequency but more of a range. So you do want to match the ranges as best you can.

Really skinny antennas do tend to be more narrow, though.
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Karl Winkler

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Re: Half wave antennas.... Are they "really" frequency-specific???
« Reply #3 on: May 14, 2024, 04:19:46 PM »

The Shure ones, and probably other decent quality center-fed dipole antennas, aren't really tuned to a specific single frequency but more of a range. So you do want to match the ranges as best you can.

Really skinny antennas do tend to be more narrow, though.

A center-fed "dipole" antenna has a center frequency, and then a bandwidth. The SNA600a from Lectrosonics, for instance, covers about +-50 MHz from the center, before there is more than 3dB of loss.
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Scott Holtzman

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Re: Half wave antennas.... Are they "really" frequency-specific???
« Reply #4 on: May 15, 2024, 12:58:56 AM »

A center-fed "dipole" antenna has a center frequency, and then a bandwidth. The SNA600a from Lectrosonics, for instance, covers about +-50 MHz from the center, before there is more than 3dB of loss.


That is correct, the farter you get from the resonant frequency the more RF energy is reflected back to the source.



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Scott AKA "Skyking" Holtzman

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John Roberts {JR}

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Re: Half wave antennas.... Are they "really" frequency-specific???
« Reply #5 on: May 15, 2024, 09:43:59 AM »

Half a wave(length) of what... The name  implies a frequency range.

JR
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Frank Koenig

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Re: Half wave antennas.... Are they "really" frequency-specific???
« Reply #6 on: May 15, 2024, 01:20:40 PM »

Really skinny antennas do tend to be more narrow, though.

This is consistent with my recollection. Thicker elements tend to broaden the useful frequency range of a dipole, or dipole derived, antenna. This is why you often see VHF and UHF antennas made of pipe rather than thin rod, aside from wind and ice resistance and power handling ability.

There are some "magic" antenna designs that have very broad bandwidth. The discone is probably the all-around winner, able to achieve a 3 octave range, while the log-periodic does quite well too. Each has other plusses and minuses. Antennas are a lot like speakers or microphones in that regard.

--Frank
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Brian Jojade

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Re: Half wave antennas.... Are they "really" frequency-specific???
« Reply #7 on: May 15, 2024, 03:00:53 PM »


That is correct, the farter you get from the resonant frequency the more RF energy is reflected back to the source.

Quoting this so Scott can't edit the history away. LOL
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Brian Jojade

Scott Holtzman

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Re: Half wave antennas.... Are they "really" frequency-specific???
« Reply #8 on: May 15, 2024, 03:24:47 PM »

Quoting this so Scott can't edit the history away. LOL


LOL, I go back and fix my typos no secret.


That should have been farther.  Farter I would be talking about myself.



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Scott AKA "Skyking" Holtzman

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ProSoundWeb Community

Re: Half wave antennas.... Are they "really" frequency-specific???
« Reply #8 on: May 15, 2024, 03:24:47 PM »


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