Muting circuit for a television receiver
First Claim
1. Apparatus for muting signals transmitted over a relatively low frequency transmission path in a television receiver of the type having channel selector means for producing a channel select signal to select a corresponding one of a plurality of presettable channels and tuning means responsive to said channel select signal to tune said television receiver to said corresponding channel, said apparatus comprising means for providing a predetermined channel select signal when a predetermined channel is selected;
- detecting means for producing an output signal when the presence of a video signal at said television receiver is detected irrespective of the particular channel to which said television receiver is tuned;
muting signal generating means conditioned when said predetermined channel select signal is provided so as to respond to the absence of said output signal to produce a muting signal; and
a muting circuit coupled to said relatively low frequency transmission path and operative in response to said muting signal to attenuate the signals transmitted thereover.
0 Assignments
0 Petitions
Accused Products
Abstract
A muting circuit for a television receiver of the type having a tuner which is operative to select a desired channel in accordance with a channel selection operation to produce a channel select signal representing the selected channel, a detector circuit for detecting whether a video signal is present or not, a muting signal generator circuit supplied with an output from the detector circuit and the channel select signal representing the selection of a predetermined channel to produce a muting signal when the predetermined channel is selected but no output is produced by the detector circuit, and a muting circuit coupled to a low frequency signal transmission path in response to the muting signal from the muting signal generator circuit to cut off or attenuate the transmission of a low frequency signal.
-
Citations
4 Claims
-
1. Apparatus for muting signals transmitted over a relatively low frequency transmission path in a television receiver of the type having channel selector means for producing a channel select signal to select a corresponding one of a plurality of presettable channels and tuning means responsive to said channel select signal to tune said television receiver to said corresponding channel, said apparatus comprising means for providing a predetermined channel select signal when a predetermined channel is selected;
- detecting means for producing an output signal when the presence of a video signal at said television receiver is detected irrespective of the particular channel to which said television receiver is tuned;
muting signal generating means conditioned when said predetermined channel select signal is provided so as to respond to the absence of said output signal to produce a muting signal; and
a muting circuit coupled to said relatively low frequency transmission path and operative in response to said muting signal to attenuate the signals transmitted thereover. - View Dependent Claims (2, 3, 4)
- detecting means for producing an output signal when the presence of a video signal at said television receiver is detected irrespective of the particular channel to which said television receiver is tuned;
Specification