GB688063A - Improvements relating to antenna arrangements for radio-receiving apparatus - Google Patents

Abstract

688,063. Aerials. ELECTRIC & MUSICAL INDUSTRIES, Ltd. Sept. 24, 1951 [Sept. 23, 1950], No. 23353/50. Class 40 (vii). A travelling wave aerial comprises a further conductor adjacent to and extending along the mains leads of a radio or television receiver, one end of the conductor is connected through a terminating impedance to effective earthing means and energy from the other end of the conductor is fed to the receiver input. The aerial conductor 1 consists of one wire of a threecore cable, the other two conductors 1<SP>1</SP> of which supply power from the supply mains to the receiver. The leads 1<SP>1</SP> are provided with R.F. chokes 4 at the end attached to the receiver. The aerial 1 is terminated by a resistor 10 serving as a terminating impedance and connected to a coil 11 wound round the cable and constituting a " coiled earthing bar " of an effective length equivalent to a quarter of the operating wavelength. Connection of the aerial to the receiver is through a matching arrangement consisting of a series inductance 6 and capacitance 9. The junction of the capacitance 9 and the outer conductor of feeder 7 is effectively earthed by a second " coiled earthing bar " 8. In place of the network 6, 9, direct connection may be made from the elements 1 and 8 to the inner and outer of the coaxial feeder respectively and matching performed by the use of a short-circuited stub positioned suitably on the feeder.