Power amplifiers are used in wireless transmitters, broadcast transmitters, and hi-fi audio equipment. The most frequently-used device for power amplification is the bipolar transistor. However, vacuum tubes, once considered obsolete, are becoming increasingly popular, especially among musicians.
Pulse oximetry is a procedure used to measure the oxygen level (or oxygen saturation) in the blood. It is considered to be a noninvasive, painless, general indicator of oxygen delivery to the peripheral tissues (such as the finger, earlobe, or nose).ulse oximetry technology utilizes the light absorptive characteristics of hemoglobin and the pulsating nature of blood flow in the arteries to aid in determining the oxygenation status in the body.
If you have COPD and are using supplemental oxygen, pulse oximetry is an oxygen measurement technique you should know about. Learn about the benefits and drawbacks of pulse oximetry, and how to properly use a pulse oximeter at home.