09-11-2012, 02:20 PM
magnetic amplifier
Introduction
The magnetic amplifier is an electromagnetic device for amplifying electrical signals. The magnetic amplifier was invented early in the 20th century, and was used as an alternative to vacuum tube amplifiers where robustness and high current capacity were required. The magnetic amplifier has now been largely superseded by the transistor-based amplifier, except in a few safety critical, high reliability or extremely demanding applications. Combinations of transistor and mag-amp techniques are still used.
Applications
Magnetic amplifiers were important as modulation and control amplifiers in the early development of voice transmission by radio.
Useful in stage lightening
Magnetic amplifiers can be used for measuring high DC-voltages without direct connection to the high voltage.