5M10.60 - Diode PN Junction - Edison Effect

Code Number:
Demo Title:
Diode PN Junction - Edison Effect
PN Junction Diode
Area of Study:
Electricity and Magnetism
0 to 20 VDC Power Supply, 0 to 150 VDC Power Supply, Diode PN Junction Circuit Board.

Plug the 20VDC and 150 VDC power supplies into the circuit board as indicated.  Run the filament light at 12 VDC.  You may cover the bulb with a mask or other cover so that you may easily see the LED when it turns on.  Carefully turn up the voltage on the 150 VDC power supply.  When you reach a forward bias of about 60 VDC, current will start to flow turning on the LED.

  • ZhiQi Lin, Wei Zhang, and HuiJie Li, "Using Car Taillights as an Experimental Device to Demonstrate the Edison Effect", TPT, Vol. 56, #6, Sept. 2018, p. 410.

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