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Ah how things have changed. When I was learning electronics we mainly dealt with radio and TV circuits and just about the first lesson one learned was to keep leads short (reduce unwanted inductance) and use decoupling capacitors everywhere.

I recall some years later a young graduate engineer coming into my office with a rather involved circuit consisting of 30/40 TTL ICs and complaining that he'd double checked the circuit and it still didn't work. I took one look at his device then went to the draws of capacitors and handed him a handful of 0.1uF ceramic caps and told him to put them between the ICs' PS rail pins to ground which he did and to his amazement the circuit worked immediately.

He stood in amazement that I should have such insight so as to fix the problem at first glance.

How such critical knowledge can get lost in university training these days just amazes me.

My university made us use really crappy power supplies and dev boards. Nothing worked unless you first put a large bulk capacitor on the power supply's output, and small capacitors close to the components.

Also I got bitten by parasitics in capacitors very early in my career: capacitors of different face value will resonate with each other to effectively kill the decoupling network at a specific frequency (resulting, for me, in an amplifier with a nice hole in its frequency response).

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> How such critical knowledge can get lost in university training these days just amazes me.

It will probably have been taught.... but very briefly. Before going go back to analysing circuit schematics, where connections between components don't show resistance or inductance, and the capacitance of two parallel capacitors sums.

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I feel it’s a function of abstraction.

You learned when analogue circuitry was the norm. I learned when digital circuitry was simple enough that you could readily take something apart and understand it.

Now, EE courses often start with cad, simulations, digital electronics, and you end up with people building ziggurats atop an ocean of incomprehension.

It’s exactly the same thing with software.

I don’t scorn people for this, rather I see myself as fortunate for having learned in a time when the more fundamental knowledge was still worth learning - and that’s the rub - for a vast majority, it simply isn’t worth the time or energy to explore the full stack, when there’s so much to learn atop it.

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I can see how that happens when people come at things from a conceptual digital side first.

It probably doesn't help when you have a circuit diagram that while topologically correct doesn't show the relative positioning between components. The first time I saw all the decoupling caps rendered in a single chain on the side of the diagram I was mightily confused. It seemed like utter nonsense until I realised where they actually went.

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