The inconsistency of power supply in Nigeria has been a major stumbling block to the advancement of her economy and as such it is an issue that requires immediate attention. Uninterrupted power supply is critical in so many applications especially in cases like hospital operations or financial transactions. This work was born out of the need to provide a cost effective and locally available way to automate the switching between various power sources. This issue can be addressed by implementing an Automatic transfer switch which automatically switches on a backup generator in the absence of the utility supply and transfers the load to the generator. The automatic transfer switch also switches off the backup generator and connects back to the utility supply when the power comes back. The circuitry consists of time delay integrated circuits and switching relays. The present effort is a prototype design to create an automatic transfer switch that can be used in an average Nigerian household because of its affordability and simplicity of operation.

: Etching is a subtractive method that is used for the production of printed circuit boards (PCBs), where acid is been used to remove unwanted copper from a prefabricated laminate [1]. The manual method of doing this can only be used for a small number of boards and is likely to be messy [2]. Besides this, exposure to some certain kinds of etchants may have adverse effects on one’s health. On the other hand, the machines available to do this provide a cleaner and faster means and can etch many boards at a time but they are very expensive. This usually discourages their purchase among small scale Printed Circuit Board (PCB) manufacturers. But the automated etching system presented here aims at providing a method of carrying out the etching process for a PCB board in a simple, clean, safe and cost effective way. The printed circuit board is mechanically designed to support and electrically to connect electronic components using conductive tracks, pads and features etched from copper sheets laminated onto a non-conductive substrate.

The rectenna as a device, is critical for achieving long-distance wireless power transfer. The centrality of this study is focused on adding to the collective knowledge of the subject matter, by providing a new perspective in terms of an alternative design for the antenna component of the rectenna. Essentially, this study features a novel "3-point star" design which was simulated in comparison with the conventional square microstrip patch antenna design. Both designs (i.e., operating at the Wi-Fi band 2.4 GHz), were assessed in terms of simulated performance parameters: gain, directivity, return loss, radiation pattern, and efficiency. From the simulation results, the proposed "3-point star" design, though slightly less efficient exhibited improved performance over the conventional square patch alternative, in terms of gain, directivity, and return loss. For the rectifying component, a greinacher voltage-doubler (with two HSMS2820 diodes), was designed separately and simulated over a range of input power levels (10dBm-34dBm), for 220-Ω, 380-Ω and 810-Ω load resistances, respectively. A maximum conversion efficiency of 88.02% was achieved at 28dBm for an 810 Ω load resistance. All design simulations were executed using Advanced Design System (ADS) software.

Epileptic power supply, scarcity of fuel, and the ever increasing demand for power supply have given rise to the development of several off-grid and on-grid power alternatives. A single phase to three phase rotary phase converter is a machine that can generate three phase power supply from an existing single phase source. This is a cheap means of generating three phase power especially in some residential environments where access to three phase power is limited. Some home equipment such as air conditioners and refrigerators run on three phase power also workshop owners and technicians have need to operate three phase machinery which may include table saw, drilling machine, lathe machine, and any machinery that runs on three phase power.

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