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Comment by simonjgreen | Hacker News Reader

That's sounds horrific. It makes me wonder what proportion of time you'd spend massaging and debugging your lab equipment vs. actually using it?

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For an experimental physicist you basically debug until you get the data for your paper or until you find your sample is bad. So you’re debugging 99% of the time.

In many fields it’s rare to build new instrumentation. You fab with well known techniques with one subtle modification, so it’s not even clear what part of your time isn’t spent debugging.

Basically 2-3 years of getting everything to work and testing each component, than 2-4 weeks of good measurements that comprise the main results of the PhD thesis.

Shame they don’t give you any extra certification or recognition for more than two years of learning about the care and maintenance of cryogenic high vacuum systems… that’s a whole persons job in some places!

I’m not looking forward to thermal vacuum testing for my robots… because I don’t think there’s a big enough chamber in Australia… option one is (assuming funding) building a thermal vacuum chamber that can get down to GEO level vacuum with all the fun a large volume vacuum system entails… option two is shipping the entire thing to a friendly country with larger chambers (ESA in EU or NASA in the USA) but then there’s the space technology export paperwork … and I don’t know which would be worse.

And that does not include the problems with electric wires. We had an unofficial rule: after half an hour debugging the electric wires just change all of them. I still have nightmares about BNC connectors.

That’s a pretty terrible rule. Unless you’re rolling over them with chair wheels, a bad BNC cable should be easy to spot by visual inspection. In my 20 years of instrumentation work it’s rarely the cable.

It was a students' lab, where each device is connected and disconnected 2 or 3 times per day, 5 days per week. The wires get a lot of use and abuse.

Usually the problem is the tip that got slightly loose and the signal is now intermittent or null. IIRC, when we detected the wrong wire we had to put it in a box and the guy in charge of the lab equipment would fix it later.

To that rule, my team added another: when throwing away the cable, cut it in half. So nobody scrounges a cable out of the garbage can only to waste more time debugging a bad cable.

I try to do this with every cable I throw out, and encourage anyone to do the same. Flaky HDMI especially.

If you’ve got an apparatus with 20 parts (a low estimate) and they’re all independently 95% reliable (a high estimate), it’s only gonna be in a usable state 36% of the time.

It's like a high-end fighter jet. An F-22 needs 43 man-hours of maintenance per flight hour.

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