FT240-31, FT240-43, FT240-61 and FT240-77
Used material: FT240-31
Start version Tuned version for best SWR
(move the coils for best SWR)
Used material: FT240-43
Start version Tuned version for best SWR
(move the coils for best SWR)
Used material: FT240-61
Start version Tuned version for best SWR
(move the coils for best SWR)
Used material: FT240-77
Start version Tuned version for best SWR
(move the coils for best SWR)
Schematic:
Primary (left):
1 coil with 9 turns = 9 turns.
Secundary (right):
3 coils with 9 turns and = 27 turns.
Impedance primary (50 Ohms) is 9 x 9 = 81
Impedance secundary 27 x 27 = 729
Calculated impedance secundary =
(50 Ohms/81) x 729 = 450 Ohms.
FT240-31 FT240-43
FT240-61 FT240-77
FT240-31 FT240-43
FT240-61 FT240-77
This SWR / return loss result is due to tuning of the coils as shown in the picture above.
FT240-31
FT240-43
FT240-61
FT240-77
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