Power supply circuit for antenna amplifier esp. in motor vehicle - provides for direct current feed through RF-by=passed diode as alternative to separate connection from battery

摘要

The amplifier (12), receiving RF signals (11) from the antenna (10), has a power supply connection (21) linked internally to the output terminal (13) where the signal is forwarded over a pref. coaxial cable (16) to the receiver (18). Current from the battery (24) of the vehicle may be supplied either over a separate line (22), or via the cable (16) with interposition of a diode (14) of appropriate polarity. To prevent rectification of the amplified RF signal the diode is by-passed by a DC-blocking capacitor (15). ADVANTAGE - Interference-free power supply provided either over a separate line or through the antenna feeder cable itself, at low cost without need to provide for functional disturbances in amplifier or receiver.