IEC 60151-5:1964 pdf download

IEC 60151-5:1964 pdf download,Measurements of the electrical properties of electronic tubes and valves – Part 5: Methods of measuring hiss and hum.

IEC 60151-5:1964 establishes methods for measuring hiss and hum in electronic tubes and valves. These unwanted noise components can limit the sensitivity, clarity, and signal-to-noise performance of radio receivers, audio amplifiers, communication equipment, and other circuits using vacuum tubes.

“Hiss” generally refers to broadband, random noise produced by the tube or its associated circuit, while “hum” refers mainly to periodic interference related to the power-supply frequency and its harmonics. The document provides a common basis for separating, detecting, measuring, and reporting these two types of noise under defined operating conditions.

It addresses the required test arrangement, tube connections, heater or filament supply, electrode voltages, load impedance, frequency response, measurement bandwidth, shielding, grounding, filtering, and measuring instruments. The procedures are intended to minimize external interference and distinguish noise generated by the tube from noise introduced by the test circuit, power supply, wiring, or surrounding electromagnetic fields.

The standard also supports consistent reporting of results, including tube type, circuit configuration, operating point, test frequency or frequency range, measurement bandwidth, noise weighting or filtering, supply conditions, and relevant corrections. Because hiss and hum depend strongly on operating conditions and equipment sensitivity, controlled stabilization and low-noise test arrangements are essential.

Overall, IEC 60151-5:1964 supports type testing, production inspection, research, quality control, equipment design, and comparison of electronic valves by providing reproducible methods for evaluating their audible and electrical noise performance.