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This chapter discusses pitfalls encountered in bringing detector systems into operation. Common interference mechanisms — e.g., power supply noise, light leaks, RF pickup, and microphonics — are described together with diagnostic and mitigation techniques. Conventional shielding and low-mass shielding techniques are presented, e.g., field line pinning and ‘self-shielding’ sensors and cables. A detailed discussion of shared current paths (‘ground loops’) illustrates that controlling current paths is much more important than ‘grounding’, which often introduces additional noise. Techniques to control current paths at the system level, in PC board layout, at the circuit level, and through connections to integrated circuits are described. Proper placement of bypass capacitors, series resonance effects, and the choice of appropriate capacitor types and ceramic dielectrics are discussed. External noise can also be suppressed by the choice of pulse shaper, e.g., to attenuate low-frequency interference. In closing, the importance of local referencing is illustrated.

This chapter examines the war prerogative in practice from 1620 - 2012. It focuses on how the House of Commons and the executive have interacted in the exercise and scrutiny of the war prerogative. It will show that the House of Commons has played an active and influential role in the exercise of the war prerogative, despite the common assumption of an exclusive executive power. Part II describes an extraordinary period in English constitutional history, during which the Commons assumed responsibility for the war and foreign policy powers and experimented with different constitutional arrangements for their exercise. Part III, the main focus of this chapter, identifies the ways that the Commons and the executive have interacted in the exercise and scrutiny of the war prerogative. Those interactions are grouped into five types: freedom of speech and debate; the power of supply; retrospective scrutiny; parliamentary consultation before going to war; legislation.

This chapter gives pointers to the experimentalist on how to avoid artifact in the practical implementation of Pulsed Gradient Spin Echo NMR, and explores the role of the instrumental diffusion baseline. Topics covered include real-time diagnostics, sample vibration, convection, eddy currents, pulse mismatch, mains hum, power supply limitations, fringe field diffusometry, and pulse sequence compensation methods. The use of full q-space sampling is discussed. Finally, the need for operator vigilance is explained; the mere appearance of the echo signal as a Gaussian echo decay being no guarantee of a well-functioning diffusion experiment.

Infrastructures connect activism, sound, and citizenship. This chapter listens to the ways that infrastructures are generative: how they emerge from, produce, and permit different forms of political subjectivity. In Athens, citizenship is claimed and contested at street level. The author tells three stories from Athens, understood as a sonopolis, a center of political action, where citizenships are performed and protested in sound. The first story picks up from this introduction, focusing on amplification, belonging, and asking who sings the city. The second story tells of solidarity networks, and the infrastructural interventions of a community wi-fi network providing internet access to refugee housing projects. The third story is a collection of small events, listening to the everyday sonic practices of people navigating borders in the city, and their uses of mobile phones as tools of broadcast and transmission. The characters in these stories are various and multifarious: activists and hacktivists from various places, the state and municipality, the UN’s refugee agency, grassroots solidarity organizations, service providers, power supplies and the struggles over them, as well as the tools and technologies that are used to sound out claims of social citizenship. Combined, the stories show how infrastructures and citizenships are never fixed or finished. They are instead projects of competing imaginaries. In the sonopolis, migrant activisms disarticulate borders between citizens and noncitizens. In the sonopolis, infrastructures and belongings are bound together, made audible, contested and rerouted, produced and productive, emergent, iterative, adaptive, activist, creative, and fragile.