4 ms·
I had a VCR back in the day that refused to function if you opened its case. It turned out that instead of using physical switches inside it used pairs of ligh
by 13of40 3y ago
I had a VCR back in the day that refused to function if you opened its case. It turned out that instead of using physical switches inside it used pairs of lights and detectors that would give false positive results when ambient light shined on them.
- aksss 3y agoas in an optocoupler? Those are the coolest, especially for dealing with different voltages.
- alexdbird 3y agoNo, there's not any call for high voltages in a VCR, outside the feedback loop of a SMPS if it's fancy. The most common thing to use light sensors is just detecting the difference between tape and clear leader at the ends of the tape (or broken tape).