If I have a 200uh coil and I want to tune 1-5 MHz what value should the tuning cap be?
1MHz 2MHz 3MHz 4MHz 5Mhz
126pfd 31pfd 14pfd 8pfd 5pfd
Now if I mark my dial the scale does not match my Vcap values. Why?
Notice the only place it is close is with the hi value cap. The lower the cap the more the strays effect the circuit.
When the dial does not match we can measure the cap and calculate the inductor value.
1MHz 2MHz 3MHz 4Mhz 5MHz
129pfd 34pfd 17pfd 11pfd 8pfd
196uh 186uh 165uh 144uh 127uh
If we do not account for the strays it appears the inductor is changing value.
Maybe another series of scans with the adjusted values is in order?
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