Military, MIL-PRF-39007, RWR78S Series, Through Hole Resistors

Through-hole resistors are electronic components that impede the flow of electric current. They are constructed with two wire terminals that are specifically designed to be inserted into holes on a printed circuit board (PCB) or used in a breadboard, and then soldered in place. These resistors are widely used in electronic circuits for their reliable performance and ease of installation. Through-hole resistors possess various characteristics that define their functionality. The first characteristic is resistance, which represents the opposition to current flow and can range from 0 ohms to 500 G ohms. The resistance value determines how effectively the resistor restricts the flow of current in a circuit. Tolerance is another important characteristic of through-hole resistors, indicating the permissible deviation from the specified resistance value. Tolerance values can vary from being virtually zero (jumper) to a range such as ±0.001% to ±5%. The tolerance specification ensures that the resistor's resistance remains within an acceptable range. Power rating is a crucial consideration when selecting through-hole resistors. It represents the maximum amount of power the resistor can safely dissipate without getting damaged. Power ratings are typically measured in watts and depend on the resistor's physical size, construction, and materials used. Through-hole resistors come in various compositions, each offering different performance characteristics. Common compositions include carbon composition, carbon film, ceramic, metal element, metal film, metal foil, metal oxide film, thick film, thin film, and wirewound. Each composition has its own advantages, such as stability, precision, durability, or suitability for high-power applications. In summary, through-hole resistors are electronic devices used to impede the flow of electric current. They have two wire terminals for insertion and soldering onto a PCB or breadboard. These resistors exhibit different characteristics, including resistance, tolerance, power rating, and composition, which determine their suitability for specific applications. By selecting the appropriate through-hole resistor, engineers can ensure reliable and efficient operation of electronic circuits.