Based on your query, the part number **40468** (often referenced as **RCA 40468** or **Motorola 40468**) refers to a classic NPN Silicon Transistor. This component was widely used in consumer electronics, particularly in television horizontal-output circuits and audio amplifiers during the late 20th century. --- ### 1. Technical Specifications The 40468 is a high-voltage power transistor designed for switching and linear applications. Below are the typical characteristics: | Parameter | Value | | :--- | :--- | | **Material** | Silicon (Si) | | **Polarity** | NPN | | **Case Style** | TO-66 (Metal Can) | | **Max Collector-Emitter Voltage ($V_{CEO}$)** | ~300V | | **Max Collector Current ($I_C$)** | ~0.5A to 1A | | **Power Dissipation ($P_D$)** | ~5W to 10W (with heat sink) | | **Transition Frequency ($f_T$)** | Low Frequency / Audio Range | --- ### 2. Key Features and Usage Historically, this part was engineered for stability in high-voltage environments. * **Audio Power Stages:** Used in the output or driver stages of vintage hi-fi amplifiers. * **TV Circuitry:** Specifically utilized in horizontal deflection circuits and high-voltage power supply regulators. * **TO-66 Package:** Unlike the larger TO-3, the TO-66 is a medium-sized "diamond" shaped metal package, allowing for decent heat dissipation in a smaller footprint. --- ### 3. Modern Substitutes As the 40468 is largely obsolete (End of Life), hobbyists and repair technicians often look for modern equivalents. When replacing, ensure the **TO-66 footprint** matches, or use a **TO-220** with insulation if space allows. | Replacement Part | Notes | | :--- | :--- | | **2N3440** | High voltage, lower current, but common in TO-39. | | **MJE340** | Good high-voltage NPN alternative (TO-126 package). | | **NTE161** | The universal NTE replacement specifically designated for 40468. | --- ### 4. Identification Tip If you are looking at a component marked **40468**, check for the manufacturer's logo (such as the RCA "meatball" or Motorola "M"). This helps confirm the datasheet parameters, as "40468" was a house number for specific industrial runs.