Memory tuning system with dual speed programming
AssigneeZenith Radio Corporation
InventorAkio Tanaka
Life of this patent
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Abstract
An all-channel two mode television tuning system includes a counter for generating channel numbers to adjust tuning. An 82 .times. 1 bit read/write memory is addressed in a program mode by the generated channel numbers to provide locations for storage of signals for tuning to preselected channels. Counting speed selection means control the counter to provide both fast and slow speeds in the program mode permitting convenient generation of any channel numbers. In the operate mode channel numbers are again generated, logic circuitry accesses the memory locations to determine if generated channel numbers correspond to preselected channel numbers, and channel number generation is automatically stopped when correspondence with a preselected channel number is determined.
Claims4
A programmable television tuning system including:
- counting means sequentially generating channel numbers for tuning all channels;
- means communicating to the viewer the tens and units digits of channel numbers generated by said counting means;
- read/write memory means coupled to said counting means having a plurality of addressable locations for storage and recall of signals related to selected channel numbers;
- mode selection means for establishing a program mode for storage of said signals and an operate mode for recall from said memory means of said signals to cause tuning to selected channels;
- clock means selectively coupled to said counting means and producing timing pulses at regular intervals;
- and
- counting speed control means, coupled between said clock means and said counting means and operating in said program mode for changing the counting speed of said counting means to reduce the time required to sequentially generate any channel number, said counting speed control means including (1) a plurality of flip/flops interconnected for continuous binary counting, responsive to said clock means and producing at least two distinct predetermined rates of counting pulses, and (2) a selector switch for selecting between said two distinct rates of counting pulses, said distinct rates being predetermined to permit a viewer to perceive counting by tens for the faster rate and counting by units for the slower rate.
Dependencies are inferred from the claim text.