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Developing countries seeking relevance in the international community have to adopt programmes in order to achieve cost-effective economic growth. Telecommunications is one area where emphasis must be laid because of its impact on development. Since the power supply forms an essential part of any communication system it is important to chose the power supply option that has the lowest life-cycle cost. The life-cycle costs of several power supply alternatives to some telecommunication systems in Nigeria have been evaluated. A hybrid (Solar=Gen. Set) power supply option is shown to be cost-effective when compared with diesel generating systems powering telecommunication equipment and airconditioning loads. The cost of PV power supply option used for a celluphone system is about 10% of the cost of the alternative of daily battery replacement and haulage. The low teledensity in the country creates a need for bold initiatives to incorporate solar power in telecommunications network, particularly in the remote rural communities where conventional electricity is not only unavailable, but is unreliable and very costly to maintain.

The mechanism behind the formation of alloyed ohmic contacts to p-type InP doped in the 10l6 cm-3 range has been investigated. Techniques used for characterising the contacts include the scanning electron microscope (SEM), specific contact resistance measurements, x-ray diffractometry (XRD), energy dispersive x-ray analysis (EDAX) and Auger electron spectroscopy (AES). Both temperature and time of annealing were varied during the study. The results obtained using our annealing procedures indicate that the optimum contact resistance is associated with the formation of an Au-In phase. The atomic percentage of indium increases with increasing annealing temperature whilst that of gold drops. Zinc phases appear only at the higher annealing temperatures used.