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The purpose of this paper is to design, build and test a low power high frequency (HF) transmitter that can be received by the Super Dual Auroral Radar Network (SuperDARN) radar installed at SANAE IV, the 4th South African National Antarctic Expedition Station. It is proposed that it may be possible to do propagation studies using the radar and the fixed frequency, ground-based HF transmitter beacon. Interpretation of the measurements can be used to study the ionosphere, especially Travelling Ionospheric Disturbances, which are signatures of atmospheric gravity waves.

In the absence of the actual deployment of the HF transmitter beacon in Antarctica, extensive simulations have been done to evaluate the expected performance of the transmitter in relation to the SuperDARN. A field trial has been executed between Hermanus (34.4241° S, 19.2247° E) and Pretoria (34.0558° S, 18.4589° E) in South Africa. In future, the beacon will be placed at the South Pole with its antenna radiating towards SANAE IV.

The HF transmitter conforms to the power and frequency stability requirements both during propagation tests conducted between Hermanus and Pretoria, as well as when the device was exposed to temperatures that ranged from +40°C to −45°C in a thermal chamber. Propagation in Antarctica is expected to differ from the field tests conducted due to the differences in density and dynamics of the polar ionosphere, compared to the mid-latitude ionosphere.

Space weather research, including forecasting atmospheric gravity waves and determining the expected electron density profile of the ionosphere, is of great scientific interest. The data received from the HF beacon can be used to study and characterize the ionosphere of the region between the South Pole and SANAE IV. Parameters of the ionosphere, such as electron density, geomagnetic storm effects, ionospheric motions and sky wave propagation paths will be better understood from analysing the signal received from this transmitter after it has been reflected and refracted by the ionosphere.

The rapid evolution of the social alarm network in the UK during the 1980s is one of the greatest success stories of the local authority housing departments which championed their growth. Yet, during the past decade, when ‘care in the community’ became a reality and the number of older people living alone in society increased significantly, the number of connections has often grown slowly and investment in new technology has been relatively low. This article describes the features of new generations of ‘telecare’ using systems with increasing potential.

Sediment measurement is usually accessible on a periodic or distinct basis. The measurement of sediment (suspended and bedload), especially in the field, is vital in keeping essential data of sediment transport and deposition. Various techniques for measuring sediment have been used over time each with its merits and demerits. The techniques discussed in this paper for suspended sediment include bottle, acoustic, pump, laser diffraction, nuclear and optical. Other techniques for bedload measurement are; River bedload trap (RBT), CSU/FU bedload trap, Helley–Smith, Polish Hydrological Services (PIHM) device, pit and trough, vortex tube, radioactive traces and bedload–surrogate technologies. However, the choice of technique depends on multiple factors ranging from budget constraint, availability of equipment, manpower and data requirement. The purpose of this paper is to present valuable information on selected techniques used in sediment measurement, to aid researchers/practitioners in the choice of sediment measurement technique.

This paper presents a general review of selected field techniques used in sediment measurement (suspended and bedload). Each techniques mode of operation, merits and demerits are discussed.

This paper highlights that each technique has its peculiar merits and demerits. However, two techniques are generally preferred over others; the bottle sampling and the Helley–Smith sampler for measuring suspended and bedload sediment. This is because the applicability of these techniques is quite widespread and time-tested.

This review paper provides an in-depth description and comparison of selected existing field sediment measurement techniques. The objective is to ease decision-making about the choice of technique, as well as to identify the suitability and applicability of the chosen technique.

The nature of radiated radio frequency fields and the ways in which they may cause either beneficial or deleterious effects are reviewed. The uniqueness of this phenomenon in relation to the drafting of safety guides, and hence ultimately in relation to law, is pointed out. The existing strategy for the drafting of safety guides depends on the determination of “reasonable worst‐case” parameters for each of the mechanisms involved in the coupling process from source to potential hazard. The decisions on what constitutes a reasonable worse case are taken by an expert committee, but comparison of the resulting safety guides with the scant evidence of proven hazards suggests that the worst‐case view leads to a substantial overestimate of the actual hazards. It is suggested that this situation would be likely to be found to be extremely unsatisfactory if ever a hazard situation (whether proven, contended or hypothetical) were to be the result of litigation between belligerent parties. It is further suggested that substantial amelioration of this situation could result if a probabilistic view of the problem were taken. In this case the expert committee would decide on realistic probability density functions, rather than realistic worst‐case factors.

An overview of radio telemetry, concentrating on low power, short‐range systems which can be operated without equipment licences. Describes transmission mechanisms, aerials and the two main types of analogue modulation: amplitude modulation [AM] and frequency modulation [FM].Outlines the developments in radio data links and modulation schemes, the benefits of networks and the various methods of encoding data. Concludes that one of the biggest problems in radio telemetry is the different regulations across Europe making it virtually impossible to design a transmitter that is acceptable in more than one country. However, in Europe the situation is slowly changing, with new common standards for defining, evaluating and testing equipment coming into effect.

The purpose of this paper is to investigate the possibility to replace radio equipment compliance requirements based on equipment parameters with a set of simple metrics that accurately reflects spectrum utilization and spectrum-sharing efficiency.

The approach taken is to go back to the basic factors that determine radio system behavior in a shared spectrum environment: radio frequency power, duty cycle and frequency occupation. By normalizing these parameters, device specificity is avoided and a statistical perspective on spectrum utilization and sharing becomes possible.

The analysis shows that two technology-neutral metrics would be adequate to govern spectrum utilization and sharing: a spectrum utilization metric and a spectrum-sharing efficiency metric. These metrics form the core of regulatory requirements for shared frequency bands. Each shared frequency band could be assigned criteria based on these metrics that take into account the types of applications for which that band will be used.

This work is a first step that identifies the main factors that affect shared spectrum usage from a statistical point of view. More work is needed on the relationship between real-world interference and its abstraction in the spectrum-sharing rules.

The metrics proposed could be considered as the basis for a new approach to the regulation of the license-exempt spectrum, and, by extension, as the basis for generic compliance criteria. Their use would facilitate the compliance assessment of software-defined radio technology.

This work has no direct social implications.

This paper combines new work on spectrum utilization criteria with extensions of previous work on spectrum-sharing efficiency into a comprehensive proposal for a new approach to the regulation of the license-exempt spectrum.

Describes the basic principles of radio remote control, dealing specifically with safety aspects, transmitters, receivers, transmitted telegrams, the Hamming code to indicate the origination of errors, and emergency stop circuits. Concludes with the specification for DTI approval in the UK and a list of typical applications for remote control systems including cranes, ship unloaders, conveyors and ventilation fans.

Briefly reviews previous literature by the author before presenting an original 12 step system integration protocol designed to ensure the success of companies or countries in their efforts to develop and market new products. Looks at the issues from different strategic levels such as corporate, international, military and economic. Presents 31 case studies, including the success of Japan in microchips to the failure of Xerox to sell its invention of the Alto personal computer 3 years before Apple: from the success in DNA and Superconductor research to the success of Sunbeam in inventing and marketing food processors: and from the daring invention and production of atomic energy for survival to the successes of sewing machine inventor Howe in co‐operating on patents to compete in markets. Includes 306 questions and answers in order to qualify concepts introduced.