A tuned circuit is provided for connection to a transmitter of a power line communication system. The tuned circuit comprises components selected to provide a low impedance path to ground for a power line communication signal of a preselected frequency. When the transmitter is not in the process of transmitting...http://www.google.ca/patents/US4766414?utm_source=gb-gplus-sharePatent US4766414 - Power line communication interference preventing circuit
