Hacker News Reader

Comment by zild3d | Hacker News Reader

I think it's actually a fantastic intro to electronics. There's nothing you can really do with "just arduino programming", the whole point is it lets you interface with the real world and therefor encounter electronics problems by default

The article even touches on that in the first hello world

> This simple exercise it by itself incredibly interesting that opened a series of questions:

> Q: Why is a resistor needed? A: High current and increased temperature damage its delicate heterojunction structures, which eventually cause it to burnout > Q: What happens if the polarity is inverted? A: Similar to a normal diode, current will not flow and the LED will not light up. As long as this reverse power is not high, the LED will not burn and can still be used with correct polarity afterwards > Q: How to interpret its data sheet? A: There are several interesting aspects its datasheet, like the LED’s wavelength curve, operating current and voltage, etc

View on HN

I had a look at the document of the kit, and it's like the one I have: it doesn't even explain what is a current and a tension, or what is the relation between resistance, tension and current, althought it is the basic of the basic of electronics

The fact that the author uses the word heterojunction that is at the same time not useful at the first level for a beginner and not used or explained in the document shows that he was either already knowledgeable or spent a lot of time with other ressources to learn.

I'm not saying that these kits are bad, or that nowaday you cannot do many great thing with just an arduino and plug and play components, but they don't teach electronics.

Anything you recommend instead?

I see it more like the goal is to build cool stuff, learning electronics is the happy unintentional side effect as you're exposed to concepts relevant to what you want to do.

e.g. I want to build a cool robot with my kid -> oh why can't you just wire the motors directly to arduino output pins -> oh motors need a lot of current to run ...

(btw have never heard voltage be called tension, TIL)

> (btw have never heard voltage be called tension, TIL)

It's the main word for voltage in french and I checked wiki before posting. It was listed as an alternative to voltage so I kept it, but I should have realized it wasn't common

Hopefully helpful comment: "tension" is sometimes used as an alternative to "voltage" in English, but it's typically only in the case of power delivery. e.g, "high-tension 50kV power lines." I don't think I've ever seen it applied to common control panel voltages like 5V or 24V.

The official arduino starter kit teaches some beginner level information, but it is very rudimentary. It is really hard to penetrate the next level of electronics—electronic engineers will stress the importance of precise calculations where previously I was just used to putting together whatever components I had from a kit, with few caveats.

It was not until I tried buying extra transistors that I realized I didn’t understand anything—-and this was after taking the Georgia Tech introduction to electronics free online course. Suddenly there were data sheets and graphs, and not to mention prices. The Build Your PCB course I found myself similarly in over my head, as it felt geared towards EE’s. But I learned about KiCAD. Maybe I will give Ben Eater another try

I'll let you in on a secret: engineering the world over is mainly about rules of thumb and knowing when you need to actually do some math.

e.g., when I started my EE career, if you wanted to light up a red LED from 5V, you'd put a 330ohm resistor in series. If it was driven from 12V, then you'd use a 1kohm. Standard values that everyone has in inventory and you don't need to think about it. Similar "rules" would apply if you wanted to use an NPN transistor as a switch and so on.

Actual calculations would only come into play if I needed to e.g., make sure that the LED always had a constant 15mA through it whether the drive voltage was 5V or 24V.

Reply on news.ycombinator.com