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Comment by WalterBright | Hacker News Reader

I've seen what happens in engineering with those with low SAT math scores. They need others to do the math for them, or they just wing it.

I remember one who was trying to reduce the noise in an electronic amplifier. He spent days trying random things. Another engineer asked what he was doing, did a quick calculation, and put in an RC circuit that solved the problem.

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Off-topic, but can an RC circuit really reduce noise? I can see how it would reduce distortion (which is not the same as noise), but adding passives is surely going to increase thermal noise?

You are correct, but an RC circuit is part of the amplifier circuit and you can do a lot to improve the signal to noise ratio (SNR) depending on frequencies/signals are trying to amplify versus the ones you want to filter out.

I see, so you want to band-limit the noise, and are willing to accept potentially raising the noise floor in the band-limited range, the idea being that if the original noise is sufficiently broad-band, this will still increase SNR?

Noise doesn’t have to be broadband. 60Hz is a common noise in US from the AC line frequency. Then there are harmonics of that due to rectifiers.

Fair enough: I was reading the original comment as referring to (thermal) noise intrinsic to the amplifier design itself (as opposed to noise due to imperfections in DC supply or due to coupling with some external transmitter), but this makes more sense, and we should consider the whole system anyway.

The problem here seems to be that the person was unwilling or unable to ask for help when they needed it, not that they don't know math per se.

I don't know how to do that either, but "winging it" is not something that would occur to me. First I'd Google it and try to figure it out. If it turns out to be nontrivial, I would just ask for help.

And I wouldn't feel the least bit bad about it. After all, those same highly educated folks need my help with e.g. git a lot more often than most software needs serious math :)

The problem was the "engineer" did not know how to design an RC circuit, one of the simplest electronic circuits, in Electronics 101.

Would you rather pay an engineer days to fail to solve a basic problem, or pay a real engineer 15 minutes to solve it?

No, that's not the problem, as you yourself admit in the false dichotomy you constructed in the second line of your post.

The problem is that, in your own words, they took days to fail to solve the problem. If they Googled the solution, and so it took them 30 or even 60 minutes to solve it, we wouldn't be having this conversation. If they asked their colleagues for help right away, we wouldn't be having this conversation.

Unless this particular role is going to be predominantly circuit design -- in which case I do have to wonder how this person got hired in the first place -- this is simply a stupid criterion to select on.

I would rather pay the engineer who knows how to solve problems even when they don't already know the answer, first and foremost. Beyond that, I would much rather pay the engineer who has practical, hands-on knowledge, that they don't teach in school. How to use git effectively, as already mentioned. How to debug production issues. What actions are and aren't safe to perform on a production server. What facilities the OS offers to get information about one's own process and the system itself. How different valid-on-paper approaches might actually play out in real life. When it's worth pursuing an exciting new technology, and when it probably won't be. Oh and of course, what new and updated technologies exist since your guy graduated Electronics 101 a decade or two ago in the first place.

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