Hackaday Links: September 5, 2021

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Good news from Jezero crater as the Mars rover Perseverance manages to accomplish for the first time what it was sent to do: collect and cache core samples from rocks. Space buffs will no doubt recall that Perseverance’s first attempt at core sampling didn’t go as planned — the rock that planetary scientists selected ended up being too soft, and the percussive coring bit just turned the core sample into powder. The latest attempt went exactly as planned: the cylindrical coring bit made a perfect cut, the core slipped into the sample tube nested inside the coring bit, and the core broke off cleanly inside the sample tube when it was cammed off-axis. Operators were able to provide visible proof that the core sample was retained this time using the Mastcam-Z instrument, which clearly shows the core in the sample tube. What’s neat is that they then performed a “percuss to ingest” maneuver, where the coring bit and sample tube are vibrated briefly, so that the core sample and any dust grains left around the sealing rim slide down into the sample tube. The next step is to transfer the sample tube to the belly of the rover where it’ll be hermetically sealed after some basic analysis.

Did any Android users perhaps oversleep this week? If you did, you’re not alone — lots of users of the Google Clock app reported that their preset alarms didn’t go off. Whether it was an actual issue caused by an update or some kind of glitch is unclear, but it clearly didn’t affect everyone; my phone mercilessly reminded me when 6:00 AM came around every day last week. But it apparently tripped up some users, to the point where one reported losing his job because of being late for work. Not to be judgmental, but it seems to me that if your job is so sensitive to you being late, it might make sense to have a backup alarm clock of some sort. We all seem to be a little too trusting that our phones are going to “just work,” and when they don’t, we’re surprised and appalled.

There seem to be two kinds of people in the world — those who hate roller coasters, and those who love them. I’m firmly in the latter camp, and will gladly give any coaster, no matter how extreme, a try. There have been a few that I later regretted, of course, but by and large, the feeling of being right on the edge of bodily harm is pretty cool. Crossing over the edge, though, is far less enjoyable, as the owners of an extreme coaster in Japan are learning. The Dodon-pa coaster at the Fuji-Q Highland amusement park is capable of hitting 112 miles (180 km) per hour and has racked up a sizable collection of injuries over the last ten months, including cervical and thoracic spine fractures. The ride is currently closed for a safety overhaul; one has to wonder what they’re doing to assess what the problem areas of the ride are. Perhaps they’re sending crash test dummies on endless rides to gather data, a sight we’d like to see.

And finally, you may have thought that phone phreaking was a thing of the past; in a lot of ways, you’d be right. But there’s still a lot to be learned about how POTS networks were put together, and this phone switch identification guide should be a big help to any phone geeks out there. Be ready to roll old school here — nothing but a plain text file that describes how to probe the switch that a phone is connected just by listening to things like dial tones and ring sounds. What’s nice is that it describes why the switches sound the way they do, so you get a lot of juicy technical insights into how switches work.

7 thoughts on “Hackaday Links: September 5, 2021

    1. Thanks! Really glad you liked it. This is effectively an endless research project, and there’ll be revisions to the file; it’s a huge network, and there’s always more to explore or play with. I’m unsure of how to present new stuff, especially short-form things. I’ve thought about mp3s or something (or just mu-law with a wav header; it’s not like every media player in the world won’t support it) with narration and recordings of actual calls, though people seem lukewarm overall on just linking to a sound file.

      There’s a lot of us out there, though; if you’d like to talk, there’s an IRC channel for this sort of thing: irc.libera.chat #billingexcellence

  1. About the coaster:
    One should mention that it’s 180km/h in 1.56s
    Allegedly (didn’t checked the math) 3.75g while a carrier catapult is 4g
    By untrained people. Well…

  2. Interesting Timing of the article.. For one of my ‘Projects’,I am repairing a vintage Western Electric 10 Trunk -30 Extension Manual switch board that came from a local School years ago. I just spent all afternoon Locksmithing and making a Skeleton Key so I could get it open. Now I can chase the Mice out of it.. I guess it’s almost a de-bugging Job..

    Miniature Remote Cameras are your Friend.. And a Lathe and Mill..


  3. Lately, Android Authority website conducted a poll about the Google clock app. In the poll 62% users voted the app missed the alarm. This is huge. Just imagine what a nightmare the app might have caused for the people. If Google can make such buggy apps, I wonder about the other apps I have installed on my phone.

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