A method of detecting usage of one or more electrical devices coupled to an electrical power line, an electrical power signal with a predetermined period is on the electrical power line, the one or more electrical devices place one or more noise signals on the electrical power line, the electrical power signal comprises the one or more noise signals, the method comprising: using a data acquisition device to acquire first data about the electrical power signal on the electrical power line such that the acquiring of the first data is synchronized with the predetermined period of the electrical power signal; processing the first data to create frequency domain data; and applying a feature extraction algorithm to the frequency domain data to determine a transition of an electrical state of at least a first one of the one or more electrical devices, wherein using the data acquisition device to acquire the first data comprises: determining a zero crossing and the predetermined period of the electrical power signal; and at least one of: (a) using the data acquisition device to sample the electrical power signal at a predetermined delay from the zero crossing to create two or more cyclostationary signals, wherein the first data comprise the two or more cyclostationary signals; or (b) determining a time, using a time of the data acquisition device, when to sample the electrical power signal such that the electrical power signal is sampled at a maximum and a minimum of an alternating current cycle of the electrical power signal; and sampling the electrical power signal during the maximum and the minimum of the alternating current cycle of the electrical power signal using the data acquisition device. using a data acquisition device to acquire first data about the electrical power signal on the electrical power line such that the acquiring of the first data is synchronized with the predetermined period of the electrical power signal; processing the first data to create frequency domain data; and applying a feature extraction algorithm to the frequency domain data to determine a transition of an electrical state of at least a first one of the one or more electrical devices, wherein using the data acquisition device to acquire the first data comprises: determining a zero crossing and the predetermined period of the electrical power signal; and at least one of: (a) using the data acquisition device to sample the electrical power signal at a predetermined delay from the zero crossing to create two or more cyclostationary signals, wherein the first data comprise the two or more cyclostationary signals; or (b) determining a time, using a time of the data acquisition device, when to sample the electrical power signal such that the electrical power signal is sampled at a maximum and a minimum of an alternating current cycle of the electrical power signal; and sampling the electrical power signal during the maximum and the minimum of the alternating current cycle of the electrical power signal using the data acquisition device. determining a zero crossing and the predetermined period of the electrical power signal; and at least one of: (a) using the data acquisition device to sample the electrical power signal at a predetermined delay from the zero crossing to create two or more cyclostationary signals, wherein the first data comprise the two or more cyclostationary signals; or (b) determining a time, using a time of the data acquisition device, when to sample the electrical power signal such that the electrical power signal is sampled at a maximum and a minimum of an alternating current cycle of the electrical power signal; and sampling the electrical power signal during the maximum and the minimum of the alternating current cycle of the electrical power signal using the data acquisition device. (a) using the data acquisition device to sample the electrical power signal at a predetermined delay from the zero crossing to create two or more cyclostationary signals, wherein the first data comprise the two or more cyclostationary signals; or (b) determining a time, using a time of the data acquisition device, when to sample the electrical power signal such that the electrical power signal is sampled at a maximum and a minimum of an alternating current cycle of the electrical power signal; and sampling the electrical power signal during the maximum and the minimum of the alternating current cycle of the electrical power signal using the data acquisition device. determining a time, using a time of the data acquisition device, when to sample the electrical power signal such that the electrical power signal is sampled at a maximum and a minimum of an alternating current cycle of the electrical power signal; and sampling the electrical power signal during the maximum and the minimum of the alternating current cycle of the electrical power signal using the data acquisition device.