Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
GB41155/58A
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
STC PLC
Original Assignee
Standard Telephone and Cables PLC
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Standard Telephone and Cables PLCfiledCriticalStandard Telephone and Cables PLC
Publication of GB853932ApublicationCriticalpatent/GB853932A/en
H04N5/44—Receiver circuitry for the reception of television signals according to analogue transmission standards
H04N5/50—Tuning indicators; Automatic tuning control
Landscapes
Engineering & Computer Science
(AREA)
Multimedia
(AREA)
Signal Processing
(AREA)
Television Receiver Circuits
(AREA)
Abstract
853,932. Tuning indicating. STANDARD TELEPHONES & CABLES Ltd. Dec. 19, 1958 [Dec. 24, 1957], No. 41155/58. Class 40(5). In a television receiver a voltage for tuning indication is derived from a sharply-tuned circuit L, C, coupled to a video or sound I.F. stage which feeds a gridcontrolled rectifier RO1. The cathode of the valve RO1 is biased back by a source B of positive potential, its anode supply comprising positive-going flyback pulses which are supplied over condenser C1. The anode of the valve acquires a negative potential proportional to the amplitude of the IF signal, and this is smoothed by network Rl, 2, C2 before application to a tuning indicator (not shown).