Graphic recording system

A graphic recorder system for use in recording sonar information and the like received over one or more information channels, said system comprising

• first memory means for storing in binary form information received over an information channel,
• means for recording on a recording medium a graphic representation of sequentially supplied information,
• means for reading binary data from said memory means and for applying the data sequentially to said recording means at selectable rates, and
• means for selectively inverting the binary data prior to application thereof to said recording means, to thereby produce either positive or negative graphic displays.

A graphic recorder system for use in recording sonar information and the like received over two or more information channels, said system comprising

• first memory means for storing information received over one of said information channels,
• second memory means for storing information received over the other of said information channels simultaneously with the receipt and storage of information by said first memory means,
• means for recording on a recording medium a graphic representation of sequentially supplied information, and
• means for reading information sequentially from selected memory means and for applying the information sequentially to the recording means.

A graphic recorder system for use with multiple channel underwater sonar apparatus which produces for each channel analog signals representing reflected sonar signals, said system comprising

• multiple digitizer means, each for converting analog signals received from a different channel to corresponding digital information,
• multiple memory means for storing digital information,
• means for applying digital information from each digitizer means to a corresponding memory means,
• digital-to-analog converter means for converting digital information from the memory means to corresponding analog signals,
• means for recording on a recording medium a graphic representation of signals sequentially supplied from said digital-to-analog converter means, said graphic representation displaying distances of underwater features encountered by the reflected sonar signals and having distance scale factors dependent upon the rate at which signals are supplied to the recording means, and
• means for reading information from said memory means and for supplying the information to said digital-to-analog converter means at selectable and variable rates.