The term **242-R** typically refers to a specific type of **SMD (Surface Mount Device) Resistor** or a specific high-frequency **Inductor/Transformer** depending on the manufacturer’s prefix. However, in the vast majority of electronic repair and assembly contexts, "242" is the standard marking for a resistor value. --- ## 1. The 242 Resistor Marking (SMD) In the 3-digit EIA marking system found on SMD resistors, the "242" code represents a specific resistance value. ### Decoding the Value | Digit | Meaning | Value | | :--- | :--- | :--- | | **First Digit (2)** | 1st Significant Figure | 2 | | **Second Digit (4)** | 2nd Significant Figure | 4 | | **Third Digit (2)** | Multiplier (Number of Zeros) | $10^2$ (100) | **Calculation:** $24 \times 100 = 2,400 \text{ Ohms}$ or **2.4 kΩ**. --- ## 2. Component Specifications If you are looking for a "242-R" part (often a Bourns or TE Connectivity part number), it generally falls into these categories: ### A. SMD Resistor (General) * **Resistance:** 2.4 kΩ. * **Tolerance:** Usually $\pm 5\%$ (for 3-digit codes). * **Common Sizes:** 0603, 0805, 1206. * **Application:** Current limiting, voltage dividers, and pull-up/down resistors. ### B. Inductors / Chokes (Specific Series) Some manufacturers use "242" as a series designation for **EMI suppression filters** or **Ferrite Beads**. * **Function:** Used to block high-frequency noise in DC lines. * **"R" Suffix:** Often denotes "RoHS Compliant" or "Tape & Reel" packaging. --- ## 3. How to Identify the Part on a PCB If you see "242" printed on a small black rectangular component: 1. **Check the Reference Designator:** * If the board says **R** (e.g., R102), it is a **2.4 kΩ Resistor**. * If the board says **L** or **FB**, it is an **Inductor or Ferrite Bead**. 2. **Measure with a Multimeter:** * Set the meter to the Ohms ($\Omega$) setting. * A healthy "242" resistor should read approximately $2.4\text{k}\Omega$. --- ## 4. Example Replacement Code If you are coding or searching for this part in a database: ```json { "part_type": "Resistor", "marking_code": "242", "resistance_ohms": 2400, "resistance_kiloohms": 2.4, "standard_tolerance": "5%" } ```