In this article, we show the implementation of a computer-based digital storage oscilloscope (DSO) and function generator (FG) using the computer's soundcard for off-campus acoustic experiments. The microphone input is used for the DSO, and a speaker jack is used as the FG. In an effort to reduce the cost of implementing the experiment, we examine software available for free, online. A small number of applications were compared in terms of their interface and functionality, for both the DSO and the FG. The software was then used to investigate standing waves in pipes using the computer-based DSO. Standing wave theory taught in high school and in first year physics is based on a one-dimensional model. With the use of the DSO's fast Fourier transform function, the experimental uncertainly alone was not sufficient to account for the difference observed between the measure and the calculated frequencies. Hence the original experiment was expanded upon to include the end correction effect. The DSO was also used for other simple acoustics experiments, in areas such as the physics of music.

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Experiments in photonics tend to be reserved for postgraduate laboratories, where suitable equipment and resources are available. Simple optical fibre experiments may be included in some undergraduate programs, possibly utilising polymer optical fibres with LEDs and phototransistors, or with the use of bulk optical components and glass optical fibre elements. However, real optical fibre communication systems and optical fibre sensing systems utilise more complex devices, such as optical fibre Bragg gratings. With the availability of optical components in the 850nm wavelength range, a variety of practical systems can be realised using industry standard components. We show how to mitigate a large portion of the cost associated with the implementation of experiments utilising these 850nm components. The limiting factor associated with the implementation of 1550nm based systems is the cost associated with spectral measurements in this wavelength range. Given a bench top optical spectrum analyser costs $10,000s; this is not something that can be made available to students in undergraduate laboratories in bulk. The solution was to make use of the new low cost USB based spectrometers, available from a number of manufacturers. In combination with devices such as couplers, circulators, isolators, wavelength division multiplexing filters, and Bragg gratings, all operating in the 850nm, a number of different sensing and communications systems can be realised.