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Table 2 – Parallel Capacitance Values

Desired Value Parallel Values

BAND C1, C2 C1A C1B C2A C2B

(meters) (pf) (pf) (pf) (pf) (pf)

160 1653 1500 150 1500 150

80 847 820 27 820 27

40 470 470 -- 470 --

20 240 240 -- 240 --

15 161 110 51 110 51

10 117 100 18 100 18

Construction Hints

The effective inductance of a toroid coil depends in part on the distributed

capacitance between the coil turns and between the ends of the winding. The

distributed capacitance should be kept as low as possible. The pictorial

illustration in Figure 2 show the inductor turns distributed uniformly around the

toroid core, but a gap of approximately 30 degrees is maintained between the

ends of the winding. This method is recommended to reduce the distributed

capacitance of the winding. The closer the ends of the winding are to one

another, the greater the unwanted capacitance. Also, in order to achieve the

desired toroid inductance, the winding should be spread over the core as shown

in Figure 2.

Figure 2 – Toroid Winding Pictorial

1 2 3 4 5 6

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