This equipment standard, developed by the Law Enforcement Standards Laboratory of the National Bureau of Standards, established minimum performance requirements and test methods for evaluating continuous signal-controlled selective signaling. The principal terms used in the document are defined. The minimum performance requirements for each characteristic are assigned a value which meets or exceeds those published by the Federal Communications Commission. User information is supplied and test sequences are listed. The ability of the equipment to operate in environmental extremes must be determined by test methods described in this report. Environmental characteristics of temperature, humidity, vibration, and shock are defined for test purposes. Standards are fixed for modulation code frequencies, radio receiver/decoder characteristics, and radio transmitter/encoder characteristics. Test conditions include temperature, relative humidity, power-supply voltage, test frequency, and test modulations. The quality of test equipment, which is critical in making the measurements discussed, is established for the following equipment: FM signal generator, code generator, frequency counter, audio generator, code distorting unit, and test receiver. Standards tables, diagrams, and 11 references are provided.