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If the telephone line is subsequently reused to support applications that require higher frequencies, such as in analog or digital carrier systems or digital subscriber line (DSL), loading coils must be removed or replaced. American early and middle 20th century telephone cables had load coils at intervals of a mile (1.61 km), usually in coil cases holding many. This increases the flux linkages, without which the number of turns on the coil would need to be increased. Above the cutoff frequency, attenuation increases rapidly. The cutoff effect is an artifact of using lumped inductors. The term is also used for inductors in radio antennas, or between the antenna and its feedline, to make an electrically short antenna resonant at its operating frequency. The term originated in the 19th century for inductors used to prevent signal distortion in long-distance telegraph transmission cables. Finally, Heaviside made the proposal (1893) to use discrete inductors at intervals along the line. The loading coil is often placed at the base of the antenna, between it and the transmission line (base loading), but for more efficient radiation, it is sometimes inserted near the midpoint of the antenna element (center loading).

Another type of loading coil is used in radio antennas. The more commonly used is shown below in bold type. A more engineer friendly rule of thumb is that the approximate requirement for spacing loading coils is ten coils per wavelength of the maximum frequency being transmitted. Also, two years later the FCC was still making rules and had, in fact, made more rules than many of the other governmental Departments combined. This was a two-needle system using two signal wires but displayed in a uniquely different way to other needle telegraphs. The appearance of a Macintosh with a direct Ethernet connection also magnified the Ethernet and LocalTalk compatibility problem: Networks with new and old Macs needed some way to communicate with each other. Increasing G is highly undesirable; while it would reduce distortion, what is control cable it would at the same time increase the signal loss. A loading coil or load coil is an inductor that is inserted into an electronic circuit to increase its inductance. Series compensation can be thought of as an inductor connected to the circuit in series if it is supplying inductance to the circuit. To reduce losses due to high capacitance on long-distance bulk power transmission lines, inductance can be introduced to the circuit with a flexible AC transmission system (FACTS), a static VAR compensator, or a static synchronous series compensator.

Previous telegraph lines were overland or shorter and hence had less delay, and the need for extra inductance was not as great. With loading methods using continuous distributed inductance there is no cutoff. Cutoff is avoided by the use of continuous loading since it arises from the lumped nature of the loading coils. The phenomenon of cutoff whereby frequencies above the cutoff frequency are not transmitted is an undesirable side effect of loading coils (although it proved highly useful in the development of filters). The capacitively loaded antennas used at low frequencies have extremely narrow bandwidths, and therefore if the frequency is changed the loading coil must be adjustable to tune the antenna to resonance with the new transmitter frequency. The origin of the loading coil can be found in the work of Oliver Heaviside on the theory of transmission lines. His was an independent discovery: Campbell was aware of Heaviside's work in discovering the Heaviside condition, but unaware of Heaviside's suggestion of using loading coils to enable a line to meet it. The NEC is not any jurisdiction's electrical code per se; rather, it is an influential work of standards that local legislators (e.g., city council members, state legislators, etc. as appropriate) tend to use as a guide when enacting local electrical codes.

Heaviside was aware that this condition was not met in the practical telegraph cables in use in his day. The mathematical condition for distortion-free transmission is known as the Heaviside condition. Monopole and dipole radio antennas are designed to act as resonators for radio waves; the power from the transmitter, applied to the antenna through the antenna's transmission line, excites standing waves of voltage and current in the antenna element. By this point, reception had been automated, but the speed and accuracy of the transmission were still limited to the skill of the human operator. The USMT, while the main source of telegraphers and cable, was still a civilian agency. Classical CAN, which includes CAN 2.0A (Standard CAN) and CAN 2.0B (Extended CAN), primarily differs in identifier field lengths: CAN 2.0A uses an 11-bit identifier, while CAN 2.0B employs a 29-bit identifier. Auto brake wiping: Input is taken from the rain sensor (used primarily for the automatic windscreen wipers) via the CAN bus to the ABS module to initiate an imperceptible application of the brakes while driving to clear moisture from the brake rotors.