A sensor used in an IED is based on an electronic device wired into a circuit board with a detonator attached. The electronic device senses a local change, through modification of, for example: temperature (up or down ), visible light intensity level (stronger or weaker), magnetic force, pressure, invisible light intensity level (infra-red or ultra-violet), x-ray beam intensity, proximity, sound intensity level, humidity change, smoke particles, etc. Typically the sensors that respond to the changes undergo an internal change in electrical resistance—that ability to allow a certain amount of electrical current to pass. The attached circuitry then acts on the change in resistance, sending an electrical impulse to a relay, transistor, silicon controlled rectifier, and ultimately to an electric detonator. Securesearch manufactures circuitry used in training aids that demonstrate how these sensors work in IEDs.