1. Resistance characteristic
Can not be adjusted, we call fixed resistors or fixed resistors, and can be adjusted, we call it adjustable resistors. The common adjustable resistor is a sliding rheostat. For example, the radio volume adjustment device is a circular sliding rheostat. It is mainly used for voltage distribution. We call it a potentiometer.
2.By manufacturing material
Carbon film resistor, metal film resistor, wirewound resistor, non-inductive resistor, thin film resistor, etc. The film resistance is formed by evaporating a certain resistivity material on the surface of the insulating material by evaporation.
Mainly as follows:
Carbon Film Resistors Carbon Film Resistors
Carbon film resistor (carbon film resistor), commonly used symbol RT as a mark; for the earliest and most commonly used resistors, vacuum coating technology is used to spray a layer of carbon film on the porcelain rod, and then the outer layer of the carbon film is cut into a spiral The striate shape determines the resistance value according to the number of spiral patterns. The more the spiral pattern, the larger the resistance value. Finally, the outer layer is coated with epoxy resin to protect it.
Although the resistance error is higher than that of the metal film, it is cheap. Carbon film resistors are still widely used in various products, and are the most basic components of electronics, electrical appliances, equipment and information products.
Metal film resistor, metal film resistor, commonly used symbol RJ as a mark; it is also sprayed on the porcelain bar by vacuum spraying technology, but the carbon film is replaced by a metal film (such as nickel chrome), and in the metal film car The upper spiral has different resistance values ??and is plated with precious metals on both ends of the porcelain rod. Although it is more expensive than carbon film resistors, it has low noise, is stable, and is less affected by temperature. Its high precision has become its excellent metal film resistance potential. Therefore, it is widely used in advanced audio equipment, computers, instruments, defense and space equipment.