The Smell of Molten Projects in the Morning

Ed Nisley's Blog: Shop notes, electronics, firmware, machinery, 3D printing, laser cuttery, and curiosities. Contents: 100% human thinking, 0% AI slop.

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  • A Mystery Block of Electronics

    Back in the day, this surely represented an achievement in high-density electronics packaging:

    Electronics Block - 1
    Electronics Block – 1

    A view from the other corner suggests the layout wasn’t quite right:

    Electronics Block - 2
    Electronics Block – 2

    It has no identification, the transistors have house numbers, and the PCB looks like a prototype. As nearly as I can tell from the capacitor date codes, it dates back to the mid-1960s.

    Two pairs of electrically isolated and thermally bonded transistors suggest an analog Class-AB driver + amplifier or a pair of digital flipflops, but there’s no way to tell.

    Judging from the ugly solder and dislodged via rings, somebody had to apply extensive modifications after initial assembly; it trailed half a dozen red wires soldered to vias and components.

    One hopes it eventually worked…