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Comment by jacquesm | Hacker News Reader

What a spectacular failure of education.

A little bit (scolding a beginner in this way is never acceptable), but I do feel like the 555 is really overrepresented in electronics learning materials. It's a quirky little chip, so learning about it doesn't really teach you much (most of the time it's just 'hook it up like so and it does this!', not 'here's how comparators and oscillators actually work'), and it's also now almost never the best or even a good solution for any of the problems it solves.

That's true but because it is a quirky useful little chip it is for many people their first exposure to integrated circuits that are a bit more 'analog' than gates and micro controllers. Opamps are the other gateway drug I guess.

It's excellent teaching material for that reason alone, you do learn about it if you try to understand what makes it tick (there are plenty of articles about it, including blown up versions). I agree it is not the best solution for most applications but I'm happy to admit that I've actually used it in production designs (more than once, actually) where it made good sense to have a component that didn't have to be programmed. If you have a soft component on a board and a spare io line then you are usually better off doing it in some different way.

I've seen some interesting applications of 555s that would have taken a lot more hardware otherwise, one of which was an oven controller with used a thermistor to directly affect the PWM output of a 555.

It's true. They're not useful for anything not hooked up to mains.

I was meaning to add footstep-activated lights to my stairs using vibration sensors and 555 timers, but then I learned that if I tried to operate them from a battery, the 555 would drain it in hours, while a much more sophisticated ESP32-c3, would last a month in sleep mode on two coin batteries or one li-ion in the same form factor all while being part of a development board that greatly increases idle current.

I never went back to that engineering department.

I ended up befriending a former Northrop RF Engineer and a (sadly) homeless genius who was involved in early silicon valley. Those two guys were incredibly impactful on me and got me all the way up to building RF equipment.

Very neat. I'm in the midst of some interesting hacking and I really regret giving away a lot of my workshop tools in the mid 90's when it all went to software. I still have a lot of hooks in electronics and such but I just couldn't justify lugging around a couple of cubic meters of parts stock & gear. But right now I'm seriously wondering whether that was a wise decision, on the other hand that world has definitely not stood still, and the prices have come down considerably. But I'd love to have my old frequency counter and pulse generator back :)

I'm really happy that you found an alternate path because such a put-down is terrible and should have never happened in any mature education institution.

> that world has definitely not stood still, and the prices have come down considerably. But I'd love to have my old frequency counter and pulse generator back

My whole workbench is mid to late 90s HP equipment I've picked up very cheap at swap meets. I love this older stuff but it is really crazy what you can buy out of China now. The Rigol Oscilloscopes and Spectrum Analyzers are crazy. They can actually replace a lot of other test equipment and do some pretty complex analysis.

> I'm really happy that you found an alternate path because such a put-down is terrible and should have never happened in any mature education institution.

I actually had a near identical experience at a different university when seeking advice about how to read Hegel. I think this is a common issue with our academic system.

I've found that SDRs can function very nicely as impromptu spectrum analyzers.

Yes, but a successful way to prevent people from going to office hours. People generally don't become professors because they care about teaching, and universities don't reward professors for teaching.

> People generally don't become professors because they care about teaching

That's only true in the very twisted environment that is the modern research university. But universities do still exist which are focused on teaching students as the primary goal, and the faculty there love teaching.

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