The TENMA 72‑8142 is a compact bench power supply that delivers a fixed 13.8 V DC output at up to 10 A, designed for industrial and hobby applications such as mobile phone chargers, automotive audio, and radio equipment. Common failure points in this model include the input rectifier/bridge, the main voltage‑regulation IC (often a linear regulator or switching controller), and the heat sink fan or thermal protection circuitry if present; overheating can also cause the internal fuse to blow. Start troubleshooting by verifying that the unit receives proper 110–120 VAC input, checking the output with a multimeter for correct voltage under load, inspecting the power‑input capacitor and rectifier diodes for bulging or leakage, and reviewing any error LEDs or indicator lights for fault codes.[oss-gpt-20b]