Circuits don't make sense

[vxp036000]

One other important point, that hasn't been brought up yet, is that no one in their mind models mixed signal / analog circuits in the time domain.  The math gets to be ridiculous.  So, we look at the frequency domain, treating the signal as an amplitude with some phase.  Nothing else matters.  Now, modeling your impossibly difficult RF circuit becomes trivial high school level algebra.

[deephaven]

Simulators are sometimes good for this kind of thing, but also can lead to pitfalls.  I once took a working oscillator design of mine and put it in a SPICE simulator.  It didn't even oscillate.  So much for the simulator.  I've found the same to be true even for simple circuits, like audio amplifiers.  That's when I learned to create my own models for circuits (usually just with some back of the hand calculations) instead of relying on some SW package.  At least doing it myself, I know how the circuit is being modeled.  It's hard to say what assumptions the simulator makes.

Oscillators sometimes need a tiny push to make them start. In the real world, there is always a little noise around which is often all that's needed to make them start. Your simulation may have worked if you had introduced a little 'nudge' signal to get it started.

[dfnr2]

One other important point, that hasn't been brought up yet, is that no one in their mind models mixed signal / analog circuits in the time domain.  The math gets to be ridiculous.  So, we look at the frequency domain, treating the signal as an amplitude with some phase.  Nothing else matters.  Now, modeling your impossibly difficult RF circuit becomes trivial high school level algebra.

That statement reveals some bias :-)  There are plenty of very interesting and useful nonlinear analog circuits that are applied and understood in the time domain.  Even among linear applications, I can think of some examples that require careful attention to time, frequency, and even spatial domains all at once, in order to do anything useful.

Dave

[gnosis]

I can understand how an individual component works, and I can handle those simple resistor problems where you take some series/parallel resistors and work backwards to combine them into a single resistor.  But I always get lost when I look at a real circuit, even ones designed for a beginner hobbyist.  I just can't see how the signal flows, there are too many connections, branches and concurrencies. ... It's a mess.

At best I can put together a simple circuit from a diagram, but not have any real understanding of how it works as a whole.  What do I need to do to figure this out?  I've tried websites like electronics-tutorials.ws and books like Forrest Mims "Getting Started In Electronics", but they all just explain a component in isolation and then throw it in some complicated circuit and I can't see how it's interacting with everything else.

I'm also just starting out in electronics, and quickly learned that the overwhelming majority of online sources of educational material are very much lacking compared to professionally written books.

The main problem with most of the amateur instructional material is that there usually aren't enough thoroughly explained examples and exercises.  It's doing lots of exercises (with reference to well-explained theory and examples) that really gets me to finally understand the material.

The best amateur online tutorials tend to do a decent job of explaining the theory, and maybe come up with an example or two, but very rarely do they give you as many (solved) exercises as a well written textbook.

To pick a good textbook, I usually head over to the local university library and browse through their electronics section.  99.999% of the stuff there is way over my head, but they do have a decent selection of introductory material, and from that the best I've found is: "Electric Circuits Fundamentals" by Thomas L. Floyd

Some of their other textbooks also looked good, but I don't have a note of their names on hand at the moment.  I'm using the 2004 (6th edition) of the Floyd book.  I've found that the more recent textbooks are generally the better ones.  They tend to have color illustrations and color photographs, vs the two-tone illustrations and b/w photos in textbooks from earlier days, and that helps -- when they are put to good use, which good textbooks will do.  Though not exclusively true, I've found that more recent textbooks also tend to have more exercises and examples than older textbooks.  The newer ones also often have CDROMs and websites with supplementary material that could potentially be helpful (though I admit I haven't really looked in to those myself yet).

Something else I imagine could potentially help a lot is playing around with circuit simulators that are designed for educational use.  I've had a fair bit of experience with using them in some other (non-electronics) field, and they really helped.  I still need to find some good ones for electronics, though.

One more thing that's definitely helped me is to read lots of different explanations made by different people of the same thing, and looking at lots of similar (but not identical) circuits.

For example, recently I've gotten interested in linear power supplies, and started reading through every article and tutorial I could find on them.  Soon, I started to see the similarities in the various circuits.  Eventually, it sinks in and starts to make sense.

[marcosgildavid]

Hi,
I have a similar problem, I'm starting in electronics coming from a software background.
My mind seems to be "conditioned" to see circuits as programs which makes everything more confusing for me to understand...

Anyway, thing I learned that make the process of circuit analysis more simple.

Analyze the AC and DC parts separately (this works for transistors and simple circuits) the final result is the sum of both with some extra magic

Some people mentioned looking at parts of the circuit as functional blocks, this is true and it helps.
It works just like a function in a program: signal in -> magic -> signal out and it helps to simplify things.

Sometimes, things just don't make sense at all, for those cases there are books, Google and Forums

And, has with all programming languages (and almost everything in life) practice makes perfect.

Happy hacking.