Display Status:

This object is not on display at the National Air and Space Museum. It is either on loan or in storage.

Collection Item Summary:

This is the amplifier oscillator that was part of the a vibrating string accelerometer. This device is based on the fact that the frequency of a vibrating string is proportional to the suspended mass. A current passed through a wire in the presence of the magnetic field causes the wire to vibrate at its resonant frequency like a violin string. Special circuitry measures the change in vibrating frequency, due to a change in weight, and thus acceleration.

This is a miniaturized version of the instrument originally developed for use in ICBM's. It served as the prototype for an accelerometer used by Apollo 17 astronauts to measure the Moon's gravity. Dr. Alexander Voutas, its inventor, donated it to the Museum.

Collection Item Long Description:

Data Source

National Air and Space Museum

Restrictions & Rights

Do not reproduce without permission from the Smithsonian Institution, National Air and Space Museum


Credit Line

Gift of Alexander Voutsas.


  • Ceramic
  • Aluminum
  • Copper Alloy
  • Plastic
  • Synthetic


3-D: 4.4 × 4.1 × 2.5cm (1 3/4 × 1 5/8 × 1 in.)

Country of Origin

United States of America



Inventory Number


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