Varactor Diode Detection Method

Varactor Diode Testing Methods

1. Determining the Anode and Cathode
Some varactor diodes have one end marked with black, which indicates the cathode, while the other end is the anode. Some varactor diodes have yellow and red rings at both ends of the case, with the red ring end as the anode and the yellow ring end as the cathode.  diode
It is also possible to use the diode test function on a digital multimeter to determine the anode and cathode by measuring the forward and reverse voltage drops. For a normal varactor diode, when measuring the forward voltage drop, the reading is 0.58~0.65V; when measuring the reverse voltage drop, the meter shows an overrange symbol "1." When measuring the forward voltage drop, the red probe is connected to the anode of the varactor diode, and the black probe is connected to the cathode.diode
2. Judging Performance
Use an analog multimeter on the R×10k range to measure the forward and reverse resistance of the varactor diode. For a normal varactor diode, both forward and reverse resistance values are ∞ (infinite). If the measured varactor diode shows a certain resistance value in both directions or zero in both directions, it indicates the diode has leakage or has broken down and is damaged.