Ok Ok... Been thinking about this for a bit...

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burningman_77

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Please excuse me because I am still a newb. Antennas... How do they fuction??? From what I can remember, and putting it to new use, is the idea of music... A tuning fork, when struck, will vibrate to make a certain tone... transmitter. When a certain note(s) on a bass/guitar is played, the snares (coiled wire on the bottom of a snare drum) will start to vibrate (like a reciever?)... Are these the basic ideas behind the antenna? Length, thickness, coils, all contribute to good reception/delivery? And a more complex antenna, the human eardrum...
 

burningman_77

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"By adding additional conducting rods or coils (called elements) and varying their length, spacing, and orientation (or changing the direction of the antenna beam), an antenna with specific desired properties can be created, such as a Yagi-Uda Antenna (often abbreviated to "Yagi")."<--- seems kinda like what I was talking about. And this right here, was what I really wanted to know --->"The "bandwidth" of an antenna is the range of frequencies over which it is effective, usually centered on the resonant frequency. The bandwidth of an antenna may be increased by several techniques, including using thicker wires, replacing wires with cages to simulate a thicker wire, tapering antenna components (like in a feed horn), and combining multiple antennas into a single assembly and allowing the natural impedance to select the correct antenna. Small antennas are usually preferred for convenience, but there is a fundamental limit relating bandwidth, size and efficiency." Photos are really nice too!!!

All text placed in quotes("") courtesy of wikipedia... Thanks Talon!
Still so much to learn...
 

n2mdk

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You can think of an antenna as one side of a transformer, when a radio signal, which is an electromagnetic wave passes through the antenna a current is created that then enters the receiver. Having the antenna the proper length for the frequency being received make the antenna more efficient. The lower the frequency the longer the antenna needs to be. Having a properly matched antenna is much more critical in transmitting than in receiving.
This is very simplified but it gives you an idea of what the antenna does in receiving.
 

n2mdk

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That very well may be correct just like the one on my avatar picture.
It's a little more complex because it does have the ground plane radials but it is a 1/4 wave.
 
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ridgescan

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HI Jerri!!!! You're fun to read! thanks for the stuff you put out there. So wadda ya think about my switchable base coil idea for a multiband whip?
 

n2mdk

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ridgescan said:
HI Jerri!!!! You're fun to read! thanks for the stuff you put out there. So wadda ya think about my switchable base coil idea for a multiband whip?
Thank you I try to be informative and somewhat entertaining
It would work fine, in fact it does http://www.universal-radio.com/CATALOG/hamantm/4289.html
There are more examples, I had a friend that had an Apt window HF antenna that had interchangable coils. They are a compromise but can work.
This is another variation the uses a tappable coil to change the loading. http://www.gigaparts.com/store.php?action=profile&sku=ZMF-1622
 
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burningman_77

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So...

Been reading up on basic electronics to get a better understanding... Is it safe to say that (in reference to my first example), that a tuning fork acts as a transmitting antenna over audible frequencies (20Hz-20kHz) and a snare on a drum (when resonating when a certain note is played) acts as a recieving antenna over these same frequencies? Then the electromagnetic waves that are transmitted/recieved in radio communications are (put simply), in the inaudiable range for the human ear (thank god)... (I figure another such "elementry" example is when a panel in your car will vibrate when your engine reaches certain RPM ranges (vibrations, waves interrelated)).
 
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