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This article makes sense. However, it's an inaccurate leap to assume it to mean that the loaded antenna offers more gain then the straight 1/4 wave whip. It says "the coil “forces” much more current into the top section than would flow in the equivalent section of a full 90º long antenna." I was not able to find any reference that this increases gain or field strength over the unloaded 1/4 wave.

Think about this, if it could improve performance over the unloaded antenna, wouldn't we be seeing more loading take place in antennas that are designed with gain in mind? For example, why not take this theory and apply it to all Yagi beams? Surly if this change in current distribution provided an advantage in gain someone should hurry up and apply it to 11 meter 8 element beams.

I'll give you this, if your antenna is mounted in a poor location on your vehicle that blocks much of the base of the antenna, you might see an improvement with the center loaded antenna. Therefore it's the location that gives the antenna it's advantage over the unloaded one and not that the loaded antenna has any more gain. Roof mount the full length antenna for parking and talking and no loaded antenna is going to beat it.

I also see flaws in the picture used to illustrate the current distribution on the full length 1/4 wave. Look at the shaded area representing the current in the top section of the unloaded antenna. Assuming the current distribution is highest at the base and continues a similar rate of reduction as we reach the tip, that shaded area does not line up with the base current of 1 amp as shown with the loaded antenna. In fact if you follow the same angle down to the base it shows little more then half the current of that being applied to the loaded antenna. Not sure what to make of that.

<blockquote data-quote="Shockwave" data-source="post: 265460" data-attributes="member: 10882">This article makes sense. However, it&#039;s an inaccurate leap to assume it to mean that the loaded antenna offers more gain then the straight 1/4 wave whip. It says &quot;the coil “forces” much more current into the top section than would flow in the equivalent section of a full 90º long antenna.&quot; I was not able to find any reference that this increases gain or field strength over the unloaded 1/4 wave.Think about this, if it could improve performance over the unloaded antenna, wouldn&#039;t we be seeing more loading take place in antennas that are designed with gain in mind? For example, why not take this theory and apply it to all Yagi beams? Surly if this change in current distribution provided an advantage in gain someone should hurry up and apply it to 11 meter 8 element beams.I&#039;ll give you this, if your antenna is mounted in a poor location on your vehicle that blocks much of the base of the antenna, you might see an improvement with the center loaded antenna. Therefore it&#039;s the location that gives the antenna it&#039;s advantage over the unloaded one and not that the loaded antenna has any more gain. Roof mount the full length antenna for parking and talking and no loaded antenna is going to beat it.I also see flaws in the picture used to illustrate the current distribution on the full length 1/4 wave. Look at the shaded area representing the current in the top section of the unloaded antenna. Assuming the current distribution is highest at the base and continues a similar rate of reduction as we reach the tip, that shaded area does not line up with the base current of 1 amp as shown with the loaded antenna. In fact if you follow the same angle down to the base it shows little more then half the current of that being applied to the loaded antenna. Not sure what to make of that.</blockquote>

[QUOTE="Shockwave, post: 265460, member: 10882"] This article makes sense. However, it's an inaccurate leap to assume it to mean that the loaded antenna offers more gain then the straight 1/4 wave whip. It says "the coil “forces” much more current into the top section than would flow in the equivalent section of a full 90º long antenna." I was not able to find any reference that this increases gain or field strength over the unloaded 1/4 wave. Think about this, if it could improve performance over the unloaded antenna, wouldn't we be seeing more loading take place in antennas that are designed with gain in mind? For example, why not take this theory and apply it to all Yagi beams? Surly if this change in current distribution provided an advantage in gain someone should hurry up and apply it to 11 meter 8 element beams. I'll give you this, if your antenna is mounted in a poor location on your vehicle that blocks much of the base of the antenna, you might see an improvement with the center loaded antenna. Therefore it's the location that gives the antenna it's advantage over the unloaded one and not that the loaded antenna has any more gain. Roof mount the full length antenna for parking and talking and no loaded antenna is going to beat it. I also see flaws in the picture used to illustrate the current distribution on the full length 1/4 wave. Look at the shaded area representing the current in the top section of the unloaded antenna. Assuming the current distribution is highest at the base and continues a similar rate of reduction as we reach the tip, that shaded area does not line up with the base current of 1 amp as shown with the loaded antenna. In fact if you follow the same angle down to the base it shows little more then half the current of that being applied to the loaded antenna. Not sure what to make of that. [/QUOTE]

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