Rádio Sharp BX-338 (1962): da sucata ao pleno funcionamento

The rescue of this Sharp BX-338 radio, manufactured in 1962, turned into a true electronic investigation. The device arrived in a very critical state, with a damaged cabinet, signs of battery leakage, intense oxidation on various metal components, and evidence of past interventions. The restoration began with mechanical repair and a complete cleaning of the assembly. Following this, a series of measurements verified that the local oscillator was functional, directing the diagnosis to other stages of the circuit. From there, the project evolved through tests with a signal injector, signal tracer, and detailed analysis of the IF chain, detector, and audio stage. Throughout the process, several problems were identified, including a defective detector diode, the absence of a decoupling capacitor, a compromised encapsulated RC network—reconstructed from the analysis of the electrical schematic—and severely degraded electrolytic capacitors. After a complete recap, preserving the original appearance of the components, and an initial calibration of the intermediate frequencies, the radio fully recovered its performance. If you enjoy classic electronics, restoring vintage radios, and diagnostic techniques, subscribe to the channel and follow our upcoming projects. Every new radio is an opportunity to learn a little more about the engineering that marked the golden age of transistor radios.