This paper introduces a differential ECG amplifier -with three operating amplifier and high input impedance, and a QRS complex detector that is composed of pacer reject circuit, QRS complex filter, all--wave rectifier, peak holding circuit, automatic gair controller, clamp circuit, monostable trigger, and lead-fail detector.

The development and application of a two-channel amplifier for bio-signals;

Constant gain amplifier using negative-resistance technology;

Measuring the noise parameter by means of locked amplifier;

For improving the performance of dense wavelength-division multiplexing(DWDM) transmission system,the optimized design of the DWDM system devices is implemented,including that a novel configuration scheme of the optical amplifier and the forward error correction(FEC) technology in optical transponder unit(OTU).

By introducing high power optical amplifiers and suppressing the optical carrier with optical filtering,.

This paper reviews three optical amplifiers principle and application status,analyzes the properties and research status of four main types of materials of optical waveguide amplifiers,and indicates that non-oxygen glass and silicon-based materials have good potential of making optical waveguide amplifiers.

A Design of ATX Power Supply Based on Magnetic Amplifiers

Three magnetic amplifiers, such as adjustable-damper controlling, speed-limited protection in deceleration segment, and automatic braking largely used in alternated-elevator system in nation's coal and metallurgy exhibit quickness and firmness.

A design of contactless charging circuit based on magnetic amplifier is presented.