5M10.57 - Tunnel Diodes

Code Number:
Demo Title:
Tunnel Diodes
Characteristics of a Diode
Area of Study:
Electricity & Magnetism
1730a Power Supply from 5th floor electronics lab, Current and Volt Meters, Tunnel Diode, 1000 Ohm Resistor.

Place the power supply, current meter, 1000 Ohm resistor, and tunnel diode in series.  Place a volt meter across the tunnel diode.  Turn up the voltage on the power supply very slowly.  As you turn up the voltage you should see the current rise also up to a threshold value of 1.69 ma.  Above 1.69 ma the current will fall dramatically and the voltage will jump to over 1 volt.  

You can also monitor the action of this circuit with an oscilloscope.

  • James Lincoln, "Quantum Tunneling Experiments with Tunnel Diodes", TPT, Vol. 59, #1, Jan. 2021, p. 76.
  • 'TD-II' Tunnel Diodes instructions, RCA, 1968.

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