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615 points thunderbong | 2 comments | | HN request time: 0s | source
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skopje ◴[] No.45650998[source]
The triggering scheme is completely brilliant. One of those cases where not knowing too much made it possible, because someone who does analog debug would never do that (because they would have a 50k$ scope!.
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monster_truck ◴[] No.45651041[source]
Does anyone have a $50,000 scope they could just give to this dude? He seems like he would make great use of it.
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nerdsniper ◴[] No.45652435[source]
Honestly I think if we each wrote a nice personal letter to Keysight they’d probably gift him one in exchange for the YouTube publicity. Several other electrical engineers on YT get free $20-50k keysight scopes not just for themselves, but once a year or so to give away to their audience members.

And yes, this person could make use of it. His videos are among the highest quality science explainers - he’s like the 3B1B of first principles in physics. Truly a savant at creating experiments that demonstrate fundamental phenomena. Seriously check out any of his videos. He made one that weighs an airplane overhead. His videos on speed of electricity and speed of motion and ohms law are fantastic.

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generuso ◴[] No.45652938[source]
What this experiment does is very similar to how an ordinary LIDAR unit operates, except that during a LIDAR scan the laser and the receiver are always pointed in the same direction, while in this demonstration the detector is scanning the room while the laser is stationary and is firing across the room.

But in principle, a LIDAR could be reconfigured for the purposes of such demonstration.

If one wants to build the circuit from scratch, then specifically for such applications there exist very inexpensive time-to-digital converter chips. For example, Texas Instruments TDC7200 costs just a few dollars and has time uncertainty of some tens of picoseconds.

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1. jonah ◴[] No.45656032[source]
And "Flash LIDAR" captures every pixel all at once. (But the frame rate is limited by how quickly the buffer can be read out and the sensor readied for the next frame.)
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2. generuso ◴[] No.45658917[source]
Quite right. There are many different kinds of depth sensors in addition to the canonical old school rotating mirror LIDAR.

I think some of the short range depth cameras (Kinect v2 was one) use time-of-flight technique, and could in principle be reconfigured to perform a similar demonstration, though it would not be as "homemade" and cool as the system built for the Youtube video.