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Comment by vukmir | Hacker News Reader

I enjoyed reading this story. Hunting down those kind of bugs is not something most of us will ever be able to do.

I'm surrounded at work by at least a dozen HALT (Highly Accelerated Life Test) chambers, and many, many of our engineers and QA people debug and test code with thermocouples connected to the system they are working with. Anybody with a EE will have lots of stories of debugging temperature related bugs on their systems - it's a (relatively) easy variable to both quantify, measure, and replicate - and the components you are working with are all temperature rated.

Combine RF + Temperature + Antennas - Then you are in for several months of interesting debugging - particularly if you want to optimize for performance at low power transmission over a wide variety (-55 to +85 Celsius) of temperatures. The math gets hinky really quickly.

We had one particularly bad customer experience on some wireless lighting control systems (power electronics and RF in a tight package) where some nodes would randomly drop from the network and couldn't be controlled.

After two sets of embedded engineers trying to solve the problem with software updates, our RF guru got involved.

He traced the problem to the RF transceiver losing PLL lock at high temperatures and the transceiver not setting the PLL status bit correctly. We had to fix our uC to reset the RF chip every X minutes based on worst-case temperature rise scenarios.

No one else would have figured this out for months. The bug had not been fixed through three generations of this transceiver and the guru had dealt with the issue years ago.

It depends hugely on which industry you work in. I'm developing SW for mobile phones and it's not been too long ago I had to use a climate chamber to debug a memory chip that was sensitive to temperature. There was also an issue with USB that failed to enumerate at -20C.

I haven't used it yet but we have some really cool (ha!) equipment that will adjust the temperature from -20 to +60 (Celsius) in minutes.

How large are those chambers? Where I work we have massive thermal chambers (about 20 feet x 40 feet or so) but there is no way they can achieve that rapid a temp swing.

I really hate going in those things when they're testing at high temp and high humidity, especially when I'm dressed for winter weather.

That's not really true, beware not to fall into a "Golden Age Fallacy". I am sure many of us will be able to debug stuff even more crazy than that. Just look at all those hardware startups popping up lately. Let's check back in 20 years.

I agree that there are some very interesting hardware startups and that we will read some great stories in 20 years, but I disagree that the most of us will have a chance to work on them. I'm under the impression that the average HNer is working on some location aware social networking mobile thingy.

This is not a "in the days of old, when men were men and women were men, too" kind of thing. Most of us will, probably, spend the next 20 years doing the web/mobile stuff.

And the rest of us are working on fancy "CRUD" applications.

I enjoy working on hardware and RF projects as a hobby. Not much fun doing it at a large corporation anymore....

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