IEEE 111-2000

This standard pertains to electronics wide-band transformers transmitting power within a wide band of frequencies covering typically at least one decade in the frequency spectrum. It is not intended to apply to transformers optimized to operate within a narrow band of frequencies. Transformers used in, or in conjunction with, wire line communication facilities serving power stations are excluded due to the special protection requirements involved. Provision is made for including data for use in the design of feedback amplifiers and control networks, or other circuits in which the knowledge of the transformer amplitude and phase frequency response is needed by the system designer. These transformers are required to transform voltage within specified tolerances of amplitude and phase when operating between specified impedances. Guides to application and test procedures are included. The annexes within this standard contain certain precautions and recommended practices. This standard also pertains to hybrid transformers, primarily used in the telecommunications industry. The hybrid transformer is a wide-band transformer used in a manner which makes it part of a capacitance, resistance, and/or inductance network, and it must have characteristics which permit it to match the network for proper overall performance.