[Link: sim.okawa-denshi.jp]

One thing I learned from other sites as far as the math goes, R1 always equals R2. C1, C2 and C3 are usually the same value, usually in pF to attenuate the MHz spectrum and to keep the attenuatd segment of the spectrum as small as possible R3 = 1/4 of R1. The use of potentiometers is important to be as precise as possible because the tollerances on a standard resistor can be from 2% to 10%. Also, the results are in Hz, so when you get the results, make sure you count 9 digits before the ".".

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