Are there large-range variable capacitors


I want to use a variable non-polarized capacitor which can vary between 10 pF to 1 μF, or at least up to 100 nF.

I can only find trimming caps which can only go up to 100 pF.

Am I looking for something that does not exist?

Best Answer

Are there large-range variable capacitors?

If I need to be able to adjust capacitance that is somewhat larger than normal trimmers, I use a hexadecimal switch and 4 fixed value capacitors. So, if you need to vary capacitance up to 100 nF I'd use a 47 nF for the "8" position on the switch, a 27 nF on the "4" position on the switch, a 15 nF on the "2" position and a 7n5 on the "1" position. Then if I wanted to go deeper and fill in the gaps (if there were any) I'd employ a secondary hexadecimal switch using a much smaller range of capacitors.

Keep getting lower and lower until you can add a trimmer.

Hexadecimal switch (plenty to choose from and not pricey either): -

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