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Multipactor is a much studied resonant AC discharge that is harmful to microwave components and circuits. There is substantial current interest in this topic because of its threat to satellite communications. In this paper, an analytical transmission line model is presented to assess the effects of multipactor, should it happen, on the distortion of a signal. The model is applicable to any input signal (analog or digital) once the electron multipactor current it causes is specified. Examples using planar and coaxial transmission lines are given on a simple dynamical model of the multipactor current. Single and multitone signals are treated, with some results presented in the In-phase and Quadrature plots.

In this letter, we comment on the applicability of the derived characteristic equation (Eq. (7)) in a recently published article of Guoxin [Rev. Sci. Instrum. 86, 014704 (2015)]. To validate our comment, we first derive another characteristic function for determination of complex permittivity of dielectric materials for the configurations considered in the above article using calibration-independent uncorrected S-parameters for transmission-line measurements (coaxial-line, waveguide, free-space, etc). Unlike the characteristic equation in this article, the characteristic equation derived here for determination of the complex permittivity of liquid samples does not require any knowledge about the complex permittivity of plugs, used for holding liquid samples in place. We then performed 3-D full-wave simulations for the measurement configurations presented in Guoxin’s article for substantiation of the characteristic equation derived in this letter.

A two-channel source of Cherenkov superradiance pulses with the electron-wave systems of identical geometry which is capable of producing 2 × 0.3 GW pulses of duration 2 ns and center frequency 10 GHz has been developed and explored. The channels are powered by a high-voltage driver whose pulse is split into two pulses that are sent through parallel transmission lines. To shorten the voltage rise time in each channel, identical NiZn ferrite-loaded coaxial transmission lines with independently controlled axial bias fields are used.

An x‐ray source driven by a 10‐pps Nd–YAG laser is described which, because of its high peak power and automatic synchronization to the laser, is especially suited for the study of x‐ray optical interactions. The device is of very simple construction, is based upon a 1‐m‐long 3‐Ω coaxial transmission line charged to 40 kV, and delivers 20‐ns wide pulses at peak currents of ∼3 kA. A simple analysis which is in good agreement with experiment predicts that a 1‐Ω line charged to 60 kV should yield peak currents of ∼15 kA.

An established method for measuring complex rf magnetic permeability is based on the change in inductance and resistance of a coaxial transmission line upon insertion of a sample toroid. It is not necessary to wind coils on the toroid or correct for geometric demagnetization factors. The use of modern commercial impedance analyzers, as described in this paper, makes measurements from 1 kHz to 1 GHz particularly easy, fast, and accurate.

The complex dielectric constant of highly purified nitrobenzene in the region of anomalous dispersion has been determined by measuring the input impedance of a variable length of a coaxial transmission line filled with the liquid. The measurements were carried out at frequencies from 0.65 kmcps to 3.00 kmcps in the temperature range between 15°C and 50°C. Good agreement was observed with an expression suggested by Cole and Cole, and the critical frequencies in this temperature region were found to be between 3 and 6 kmcps.

A reflectionless termination design is described which, in principle, can be adapted to wave‐guide or coaxial transmission lines. Reflection coefficients of 0.001 were obtained experimentally with X‐band wave‐guide terminations. The termination comprises a section of transmission line into which is fitted a tunable sliding load. The sliding load is tuned to be reflectionless by means of the ``sliding load'' method of measuring reflection coefficients. The termination can be operated over a wide frequency range but must be retuned each time the frequency is changed.The wave‐guide circuit of the load is analyzed and design equations are derived.The reflectionless wave‐guide termination is primarily useful as a reference standard for microwave impedance bridges.

Microwave and photometric techniques are used to study the temporal and spatial behavior of a transient microwave‐generated air plasma sheath in a coaxial transmission line. In particular, breakdown times, stabilization times, and thickness of the ionized sheath are investigated at different pressures and generating signal amplitudes.

The azimuthally symmetric modal spectrum for the azimuthally magnetized ferrite‐loaded coaxial transmission line and the ferrite‐loaded wire are presented on normalized ω‐β diagrams. Practical considerations of magnetic biasing are discussed.

A method for subnanosecond pulse measurements of I‐V characteristics is described. The sample is mounted at the end of a transmission line and the incident and reflected pulse is observed. In this way the sample resistance is compared with the known impedance of the coaxial transmission line and no current measuring series resistance is needed. Short pulse risetimes (170 psec) are obtained and difficulties which arise from the current measuring resistor, like temperature dependence and nonlinearity at high currents, do not obscure the measurements.