Abstract: A fluid treatment apparatus includes a ferrite assembly, a driver, and an oscillator circuit. The ferrite assembly is arranged in use to be capable of surrounding a conduit containing fluid to be acted on. The driver is arranged to generate a pulsed current to which the ferrite assembly is subjected whereby the driver is electromagnetically coupled to the ferrite assembly. The oscillator circuit is electromagnetically coupled to the ferrite assembly, and in response to the pulse generated by the driver, causes an oscillating signal to be generated which gives rise to an electromagnetic field which acts on the fluid in the conduit.

Abstract: An electrical circuit arrangement includes a conductive link through an insulating layer separating two conductive layers. This link is formed by placing an evaporable plug on a first conductive layer, forming the insulating layer around it and then vaporising the plug. The resulting gap is then infilled with conductive material and a second conductive layer formed on the insulating layer.