Glossary of Terms

Buried conductor. See "Stripline". p17.

Catt Anomaly. (Now 2014 called The Catt Question ) First described in Wireless World, aug81. When a voltage step travels down a two wire transmission line, more and more negative charge must appear on the lower line to terminate the electric flux. This has to travel from the left at the speed of light, but in that case the electrons have infinite mass. p31. [My 1996 book The Catt Anomaly pub. Westfields, is on my website www.electromagnetism.demon.co.uk/ ]

The Catt Question

Characteristic impedance. If the front end of a long coaxial cable behaves like a 50Ω resistor, then we say that the line has a characteristic impedance of 50Ω. It would be more accurate if we called it "Characteristic resistance", but we don't. p24.

Crosstalk. When a signal travels down one line with ground as return path, it causes unwanted electrical noise on an adjacent signal line. Originally (1960) thought to be due to stray capacitance between the signal lines in the high voltage and low current signals used in valve circuits, the advent of lower voltages and heavier electric currents in transistor circuits moved some of the attention towards stray mutual inductance, creating a hybrid theory. Although these false rationalisations have some use when only a crude feel for the problem is needed, they must now give way to the concept of the two propagation modes, EM and OM.

DX. Differential Crosstalk. Name devised in my 1967 paper (ref.15). Differential crosstalk arises in surface lines because the Even Mode and the Odd Mode signals have different propagation velocities. The faster, negative OM arrives at the far end of the passive line before the (partly cancelling) EM signal. DX reaches a maximum of about 50% of the original signal, but only in very long lines. Fig. 49, p18 gives the velocity difference which causes DX. Fig. 50, p19.

EM. Even Mode. p16 One of the two types of signal which can travel along a symmetrical four wire system.

Energy current. p14, p28 The counterpoint to electric current. A phrase used only twice by Heaviside late last century as the foundation of his Theory H, in which the cause is energy current, or the Poynting Vector, guided along between the conductors at the speed of light, and causing the electric current and charge in the conductors, which he called "obstructors". Energy current was never mentioned again until Catt discovered it. Previous Heaviside savants Josephs, Gossick, Mercer, all of whom I have met, overlooked it. The Poynting Vector is an early version of it, and it later became the TEM Wave. (Caveat. Early writings by Heaviside used the phrase in a casual way.)

FX. Fast Crosstalk. Name devised in my 1967 paper (ref.15). A flat topped pules, the difference between the Even Mode and the Odd Mode signal which is seen on the passive line. Fig.50, p19.

Microstrip. See "Surface conductor". p18.

OM. Odd Mode. p16 One of the two types of signal which can travel along a symmetrical four wire system.

Surface conductor. Microstrip. A printed wire on the outside surface of a printed circuit board. p18.

Stripline. A printed wire sandwiched between two voltage planes in a printed circuit board. p17.

SX Slow Crosstalk. Name devised in my 1967 paper (ref.15). The degenerate case of FX, when propagation time down the passive line and back is less than the signal rise time. SX has the triangular (noise spike) shape that we are all familiar with in slower logic.

TEM Wave. Transverse Electromagnetic Wave. Fig5, p2 This neglected concept 1 is the central feature of Catt's theory of electromagnetism. Conventionally, the TEM wave has a B component in the x direction, an E component in the y direction, and travels forward in the z direction at the speed of light, 300,000 km/s (in vacuo).

Under Theory C, the TEM wave is the only physically possible expression of electric field and of magnetic field. The two fields are indissolubly linked in the ratio 377Ω (in vacuo). Further, such a field cannot be stationary. It can only travel at the speed of light. Stationary electric and magnetic fields do not exist. Fields travelling at other than the speed of light do not exist.

Theory C. First disclosed In Wireless World, dec80. The third in the sequence (p29) of fundamental theories of electromagnetism. C stands for Catt. Catt realised that when Theory H reversed the causality between electric current and field, it led to the disappearance of the need for current and charge. This excision resolves the Catt Anomaly (p31). p12

Theory H. The second in the series of theories. H stands for Heaviside. "We reverse this; the current in the wire is set up by the energy transmitted through the medium around it ..."

Theory N. The conventional theory of electromagnetism which has ruled for a century since the suppression of Oliver Heaviside and his supporters. A battery yearns to send electric current down wires. If it succeeds, this results in electric field, or flux, between the wires, and magnetic field, or flux, surrounding the current in the wires.

Transverse Electromagnetic Wave. See TEM Wave.