College of Liberal Arts & Sciences
5M10.53 - Burn or Blow a Diode
Safety Glasses are required for this demonstration!
Plug the Variac into the isolation transformer. Connect the diode directly to a Variac with an on/off switch. With the switch on the Variac in the off position, turn Variac to its maximum voltage setting. When the switch is turned on, the diode will either burn or blow dramatically.
The 1N459 diodes will blow or vaporize with a loud bang.
The 1N4001 and 1N4002 diodes are 100 volt diodes so they will slowly heat up, then glow, and then finally burn up.
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