Methods of Learning to Build Electronic Circuitry?

Peristaltic asks: "I've seen some cool articles in Instructables detailing how to create various electronic gadgets. A couple of these as well as the odd DIY kit have come to life on my kitchen table. While it's satisfying to see the things work after time spent soldering, I would love to be able to take the next step beyond the basics of component functionality, i.e. a resistor does -this-; a capacitor does -that-. Forest Mimm's books have been helpful towards this end, but it's time to move forward. Every month or so, I read here on Slashdot a plea for help getting started with, or expanding someone's knowledge of programming. OK, I'd like to make that plea for help with electronics theory & circuit building. I've found plenty of references on the web, Amazon, etc., but can someone who's already taken this trip outline what has and hasn't worked for them?"

Comments

Experiment!

[Alioth]

Experiment. Really.

I started with electronics properly in about September time. Probably the most valuable parts I have in terms of experimentation:

1. A large breadboard (the plug in type). This means you can rapidly try things out. I now have two breadboards - one small, and one large.
2. An oscilloscope. I bought a dual trace 20MHz Gould scope off an eBayer. I would have been lost without it. The dual trace is very useful too when you need to compare signals or check that things are synchronized.
3. The Internet. Seriously - some good resources:

http://www.ibiblio.org/kuphaldt/electricCircuits/ - Lessons in Electric Circuits, a free book - will get you started.

http://www.standardics.nxp.com/products/ Datasheets for every standard logic IC (4000 series and 74 series). Browse the site for chips you're interested in. They are cheap to buy from your local distributor (in Britain, you've got several choices - RS components, Maplin (a bit on the expensive side, but very fast delivery), Bowood Electronics (a superb small firm, fast delivery), Farnell (not used them yet, but they have an extensive catalogue).

http://www.wikipedia.org/ Lots of good articles. I used their article on buck and boost converters to get started on making high voltage switch mode power supplies for my first proper project.

The first thing I did on my breadboard was make simple circuits and understand them - using the versatile 555 timer, making logic gates out of discrete components, making an oscillator from transistors, capacitors and resistors. Then learned about how inductors work - how to use a small inductor to make a DC-DC converter. Comparing how bipolar transistors and MOSFETs work. Making small practical circuits like pulse generators etc. Then using logic ICs

I then built a Nixie tube display (with 7 tubes) out of raw 4000 series logic - essentially, I designed and built my own UART to receive data from a computer's RS232 port and display it on the tubes, and to be able to send data back to select what to display on the tubes. (Two pages of pictures here: http://www.alioth.net/pics/nixies/nixies.html). The nixie tube project was a great one to do as I had to learn lots of different things to be able to make it work: how to make a 170 volt switch mode power supply to the use of digital logic and how to debounce switches.

Now I've started designing and building an 8 bit computer based around the Z80, with flash ROM and static RAM plus an LCD interface etc. It actually works, too - I've got it running off a 4MHz crystal oscillator that I built. There's still a lot to learn - but I've gone from having very little knowledge of how to build electronic circuits to designing and building a simple 8 bit computer (with a keypad for input and LCD for output) in just a few months - if you're already experienced with software, learning about digital electronics is fairly natural. I can really recommend building something reasonably complex out of discrete 4000 or 74 series parts, because this is a great vehicle for learning about digital electronics, and how the real world tends to impinge on you a lot more than it does with software.

Pictures of the rat's nest of wiring that's the Z80 project is here (I've not updated it in a few weeks, I have more photos and assembler code to go in soon): http://www.alioth.net/Projects/Z80/

Why the Z80? Unlike all other processors, the Z80 has registers implemented in static memory. This means when you're experimenting, you can clock the processor arbitrarily slowly - fractions of 1Hz if you really want (or even clock it by hand). This makes early circuits A LOT easier to debug. It's not hard to program, has superb documentation free to download from Zilog. It has separate I/O