NCJ Number
94899
Date Published
1984
Length
23 pages
Annotation
This technical document establishes performance requirements and testing methods for the receiving/recording system used in surveillance work that typically includes frequency modulated (FM) receivers, cassette recorders, and their associated antennas and power sources.
Abstract
The system addressed in this standard uses a 5.76 cm/s (1-7/8 in/s) Philips-type cassette. The document defines the scope of the standard and technical terms used. A list of minimum performance standards is accompanied by explanations of individual requirements. This section first discusses information that manufacturers and distributors of receivers and recorders must provide, receiver SINAD sensitivity, receiver sensitivity characteristics of usable bandwidth, adjacent-channel selectivity and desensitization, spurious response attenuation, and intermodulation attenuation. It also considers receiver squelch characteristics of sensitivity, block, and receiver attack time and the receiver audio characteristics of output power, distortion, response, and hum and noise. Other areas addressed in the requirements section are receiver performance at temperature extremes, receiver memory retention, recorder performance, and receiver/recorder system performance. The document's final set of standards deals with test methods, initially explaining standard test conditions and equipment. Tests are described for the following: receiver SINAD sensitivity, receiver selectivity, receiver squelch, receiver audio, receiver environmental temperature, receiver memory retention, recorders and receiver/recorder systems. Block diagrams and 11 references are supplied.