Coupling of carrier signal from power line
Patent 4675579 Issued on June 23, 1987. Estimated Expiration Date: 
March 18, 2005. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
March 18, 2005. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References 2212721 2300940 2924769 3924223 Remote control of dimmable electronic gas discharge lamp ballasts Patent #: 4523128 InventorsApplicationNo. 06/713218 filed on 03/18/1985US Classes:315/318, Group control systems340/310.15, Impedance matching (e.g., Y-match or delta match)340/310.17With inductive coupling (e.g., transformer or torroid)ExaminersPrimary: Scott, SamuelAssistant: Kamen, Noah P. Attorney, Agent or FirmInternational ClassesH05B 41/39 (20060101)H05B 41/391 (20060101) AbstractThe AC power line to a street luminaire carries a 200 KHz carrier signal for operating a switching relay that connects a dimming reactor in series with the discharge lamp. A pick-off transformer has a primary winding connected in series with the ballasting means for the lamp, and a secondary winding connected to a carrier signal detector operating the switching relay. A capacitor connected across the primary has a value resonating the primary magnetizing reactance of the transformer at the carrier frequency. A resistor substantially higher in value than the characteristic impedance of the line but not several orders of magnitude higher, is preferably connected across the primary winding to serve as a terminating impedance. | |
