The antenna with VC sections C1 and C2 in parallel is tunable between 4.030MHz and 9.860MHz as is expected from the following tables.
Measured capacitance of each section of the VC
min center max
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c1 148.4pF 62.6pF 22.0pF
c2 150.3pF 65.9pF 23.5pF
c3 40.7pF 27.8pF 19.9pF
c4 40.4pF 26.9pF 19.8pF
with L=5.1uH, the capacitance should be: 3.5MHz 7MHz 10MHz 14MHz 18MHz 21MHz 25MHz 28MHz ------------------------------------------------------- 405pF 101pF 50pF 25pF 15pF 11pF 8pF 6pF