- 1). Attach the positive side of the 9 V battery to one side of the resistor. If you are using a battery holder, this is the side with the red lead.
- 2). Connect the other end of the resistor to the cathode side of the zener diode, so that it will be reverse-biased. This is the side indicated by a mark.
- 3). Wire the remaining diode terminal to the negative side of the battery. If you are using a battery holder, this is the side with the black lead.
- 4). Place the multimeter on a DC voltage setting. Measure the voltage across the diode by placing a multimeter lead on each terminal. It should read approximately 3.3 volts. Note that the voltage between the battery and ground remains at 9 V.
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