Circuit ideas and projects are intended for technically trained individuals who are qualified to evaluate their appropriateness and safety. Home-made devices are not reliable and unforeseen consequences may result from their use. Check all local, state, and federal laws regarding the use of home-made devices that transmit or connect to any utility. Do not construct and use illegal wiretaps or recording devices. Do not build bomb triggers or other illegal weapon components.
Many circuits use or generate dangerous voltages even when powered by low voltage batteries.
Many of the materials used to assemble electronic devices contain dangerous chemicals such as lead. Although the information provided is believed to be original or in the public domain, the devices and suggested uses may violate existing patents. Although practical jokes and gags can be entertaining, the involved parties may feel that they were damaged or that their civil rights were violated. Law enforcement organizations may consider electronic and electro-mechanical components to be paraphernalia for building illegal devices. Electromagnetic energy may cause disease.