
Keeping the Keck Telescopes Running - sohkamyung
http://darkerview.com/wordpress/?p=25813
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todipa
I always wondered how old machines get fixed when replacement parts are no
longer in production. This was very educational.

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ams6110
A lot of these types of installations are bespoke, at least in large part.

I used to have a friend that worked at a particle accelerator lab, they had a
complete machine shop on site so that they could make repair parts, or new
parts as needed for various experiments. These are not things you will ever
buy at Amazon or even a place such as McMaster-Carr.

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quasse
The act of unboxing a prototype PCB for the first time, soldering all the
components up by hand at the hot air station and then switching it on for the
first time (and cringing in anticipation of magic smoke or expensive bangs) is
one of my favorite things, speaking as a software engineer who dabbles with
hardware design in smaller projects for work.

It encourages really deep thought and full exploration of your design before
"compilation" (spinning a PCB), something that I don't get as much with the
quick turnaround run-error-fix-run cycle of the interpreted languages I
develop in day to day.

It reminds me more of my really early days playing with Gentoo on a Pentium II
with 128MB of RAM, where running _make_ had a real cost on a large project. It
really encouraged you to think changes through instead of just slapping some
changes in and running it to see if they were correct or not.

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madengr
That’s a great web site. Worth the time reading through his posts.

I spent the last two weeks laying out a PCB with iPhone-like density; now I
hate laying out PCBs.

It’s therapeutic until you spend too long on it, then it’s drudgery.

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dbcurtis
High desity PCBs are a challenge. Most of the time as hobbyists or for
engineering prototyping that density is not necessary. Giving yourself 10% or
15% extra space is hugely beneficial to your sanity.

Production boards are a different story, but that isn’t likely to be the first
iteration.

Article:

> The details in a PCB layout seem endless, you have to check everything
> thrice. Even after doing so you just have to accept that there will be some
> small error. Hopefully something you can live with.

At the robot club I give these encouraging words to people trying PCB design
for the first time: “PCB design is like golf. Low scores are better, but
holes-in-one are rare.”

A couple of wires tack-soldered on can salvage most boards.

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jeffrallen
Thank you for your service to science.

