For sure, it's not my training as an electronic engineer... More likely, there must be some visual qualities that make them look interesting - at least to the photographer's eye. Often, the textures of weathered or rusty devices are the first to get my attention, or the colors and how they contrast with each other: device against background, one material against another. Many times it is the pure geometry of conducts, wires and shapes that does it for me.
Gear notes: see below images
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