This 1948 training manual from the National Radio Institute serves as a foundational guide for technicians learning to diagnose and repair electronic equipment. The primary focus is on the multimeter, with detailed instructions on how to interpret various scales and safely measure voltage, resistance, and current. To protect these sensitive instruments, the text emphasizes selecting the highest measurement ranges first and ensuring proper probe connections. Beyond basic testing, the booklet introduces more advanced tools like signal generators for circuit alignment and tube testers for verifying component integrity. Ultimately, the source outlines a progressive equipment strategy, advising beginners to master essential meters before investing in specialized devices like signal tracers and R-C testers.
