Instructional Resources and Lecture Demonstrations

Electromagnetic Pickup, Amplifier, Speaker, Variac with switch, and light bulb

Code Number: 3C50.60

Demo Title: 60 Cycle Hum - Electromagnetic Pickup

Condition: Excellent

Principle: Line Noise

Area of Study: Oscillations & Acoustics

Equipment:

Electromagnetic Pickup, Amplifier, Speaker, Variac with switch, and light bulb.

Procedure:

LOOK IN THE 3B70.30 BOX for the electromagnetic pickups.

Plug the electromagnetic pickup into the Auxiliary jack of the amplifier. You will have to turn the volume on the amplifier almost all the way up. When you switch on the Variac to turn on the light bulb the 60 cycle line hum will be distinctly heard.

Disclaimer

These demonstrations are provided only for illustrative use by persons affiliated with The University of Iowa and only under the direction of a trained instructor or physicist. The University of Iowa is not responsible for demonstrations performed by those using their own equipment or who choose to use this reference material for their own purpose. The demonstrations included here are within the public domain and can be found in materials contained in libraries, bookstores, and through electronic sources. Performing all or any portion of any of these demonstrations, with or without revisions not depicted here entails inherent risks. These risks include, without limitation, bodily injury (and possibly death), including risks to health that may be temporary or permanent and that may exacerbate a pre-existing medical condition; and property loss or damage. Anyone performing any part of these demonstrations, even with revisions, knowingly and voluntarily assumes all risks associated with them.

3C50.60 - 60 Cycle Hum - Electromagnetic Pickup