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What in that article did you read that made you believe that placing a cap hat directly on top of a coil is a good idea?

A coil adds inductive reactance. A capacitance hat adds capacitive reactance. What happens when inductive reactance and capacitive reactance are the same? They cancel each other out. When you place the capacitance hat directly on top of the coil, what capacitance that was introduced is going to directly interact with that coil, shunting the inductor. There is no way around it, and whatever you're trying to accomplishing is going to get screwed up. Maybe someone else can explain it better or more accurately than I am able to.

On that Immortal, if he's trying to make a very short antenna that performs better than others with the same overall height, he should just get rid of the coil at the top, leave the hat. He would probably have to adjust the length between the coil and hat or change the number of turns in the loading coil.

<blockquote data-quote="Moleculo" data-source="post: 265900" data-attributes="member: 1">What in that article did you read that made you believe that placing a cap hat directly on top of a coil is a good idea?A coil adds inductive reactance.&nbsp; A capacitance hat adds capacitive reactance.&nbsp; What happens when inductive reactance and capacitive reactance are the same?&nbsp; They cancel each other out.&nbsp; When you place the capacitance hat directly on top of the coil, what capacitance that was introduced is going to directly interact with that coil, shunting the inductor.&nbsp; There is no way around it, and whatever you&#039;re trying to accomplishing is going to get screwed up.&nbsp; Maybe someone else can explain it better or more accurately than I am able to.On that Immortal, if he&#039;s trying to make a very short antenna that performs better than others with the same overall height, he should just get rid of the coil at the top, leave the hat.&nbsp; He would probably have to adjust the length between the coil and hat or change the number of turns in the loading coil.</blockquote>

[QUOTE="Moleculo, post: 265900, member: 1"] What in that article did you read that made you believe that placing a cap hat directly on top of a coil is a good idea? A coil adds inductive reactance. A capacitance hat adds capacitive reactance. What happens when inductive reactance and capacitive reactance are the same? They cancel each other out. When you place the capacitance hat directly on top of the coil, what capacitance that was introduced is going to directly interact with that coil, shunting the inductor. There is no way around it, and whatever you're trying to accomplishing is going to get screwed up. Maybe someone else can explain it better or more accurately than I am able to. On that Immortal, if he's trying to make a very short antenna that performs better than others with the same overall height, he should just get rid of the coil at the top, leave the hat. He would probably have to adjust the length between the coil and hat or change the number of turns in the loading coil. [/QUOTE]

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