How to measure variable capacitance with multimeter
The capacity of the variable capacitor is usually small, mainly to detect whether there is a short circuit between the capacitive moving piece and the fixed piece.
① Slowly rotate the shaft by hand, it should feel very smooth, and it should not be loose or tight or even stuck. When the rotating shaft is pushed forward, backward, up, down, left and right, the rotating shaft should not shake.
②Variable capacitors with poor contact between the shaft and the moving piece cannot be used any longer.
③ Put the multimeter in the R×10k gear, connect the two test leads to the leading end of the moving piece and the fixed piece of the variable capacitor with one hand, and slowly turn the rotating shaft back and forth with the other hand. The pointer of the multimeter should be at infinity Do not move. If the pointer sometimes points to zero, it means that there is a short circuit point between the variable capacitance moving piece and the fixed piece; There is a leakage phenomenon.
