Sf signaling system for radio frequency repeaters
CA 1051520 A · Owner: Hughes Aircraft Company · Inventors: Tustison, Galen F.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Single frequency signaling system which simulates the low level tone during the idle circuit condition even though the radio frequency carriers in the transmission link through a repeater have been turned off. Said system utilizes 2600 Hz detectors having long time constants to turn the transmitters on and off and to connect 2600 Hz oscillators to the receive lines to simulate the idle circuit condition.
Read the whole patent
Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Granted March 27, 1979. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended March 27, 1996.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.