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You do not want to add the beads into the 5 turns, it'll skew how it works, basically what frequency its tuned for, because it is an LC circuit. By adding beads you're altering the overall inductance and it'll affect the capacitance because you're also altering the spacing between the turns so therefore the capacitance between turns.

Think of a RF choke being similar to a tuned trap LC circuit for a multiband single element antenna. Alter either the capacitance or the inductance and you shift the frequency it works at because the frequency it works at is dictated by the formula

1/ 2pi√LC

What would be better is adding them to the feedline prior or after the air wound choke because they have no effect on the LC circuit. So assuming its correct as per the chart when you measure it, the choking of the two is combined so if you've 2k from the air wound choke at a certain frequency and a total of 1k from the beads ( the spec sheet should have a chart for impedance at specific frequencies for numbers of turns), you've a total of 3k at that frequency.

<blockquote data-quote="M0GVZ" data-source="post: 526452" data-attributes="member: 22312">You do not want to add the beads into the 5 turns, it&#039;ll skew how it works, basically what frequency its tuned for, because it is an LC circuit. By adding beads you&#039;re altering the overall inductance and it&#039;ll affect the capacitance because you&#039;re also altering the spacing between the turns so therefore the capacitance between turns.Think of a RF choke being similar to a tuned trap LC circuit for a multiband single element antenna. Alter either the capacitance or the inductance and you shift the frequency it works at because the frequency it works at is dictated by the formula1/ 2pi√LCWhat would be better is adding them to the feedline prior or after the air wound choke because they have no effect on the LC circuit. So assuming its correct as per the chart when you measure it, the choking of the two is combined so if you&#039;ve 2k from the air wound choke at a certain frequency and a total of 1k from the beads ( the spec sheet should have a chart for impedance at specific frequencies for numbers of turns), you&#039;ve a total of 3k at that frequency.</blockquote>

[QUOTE="M0GVZ, post: 526452, member: 22312"] You do not want to add the beads into the 5 turns, it'll skew how it works, basically what frequency its tuned for, because it is an LC circuit. By adding beads you're altering the overall inductance and it'll affect the capacitance because you're also altering the spacing between the turns so therefore the capacitance between turns. Think of a RF choke being similar to a tuned trap LC circuit for a multiband single element antenna. Alter either the capacitance or the inductance and you shift the frequency it works at because the frequency it works at is dictated by the formula 1/ 2pi√LC What would be better is adding them to the feedline prior or after the air wound choke because they have no effect on the LC circuit. So assuming its correct as per the chart when you measure it, the choking of the two is combined so if you've 2k from the air wound choke at a certain frequency and a total of 1k from the beads ( the spec sheet should have a chart for impedance at specific frequencies for numbers of turns), you've a total of 3k at that frequency. [/QUOTE]

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