signal graph sketched with white chalk on blackboard with eraser patterns

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signal graph sketched with white chalk on blackboard with eraser patterns

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Size: 4200px × 3106px
Photo credit: © Marek Uliasz / Alamy / Afripics
License: Royalty Free
Model Released: No

Keywords: black, blackboard, chalk, chalkboard, copy, drawing, frequency, graph, horizontal, pulse, signal, space, texture, white