http://www.falstad.com/circuit/e-index.htmlWow !!!
This is so cool. I'm not saying you can learn everything about electronics from it, but it does provide a very visual way of how electronics (circuits) work!
Specially interesting for some of you (I think):
Ohms Law (How resistors work):
http://www.falstad.com/circuit/e-ohms.htmlNote that anything blue can be switched (switches or Hi/Low) or values edited (right click).
F.I. here's completely clear how a capacitor works:
http://www.falstad.com/circuit/e-cap.htmlOr a diode:http://www.falstad.com/circuit/e-diodevar.html
(Edit the Voltage on top to a negative voltage and you will see no current is flowing).
Following this: half-wave rectifier (as often used on older PCB's where AC was input and the DC was created ON the game PCB.)
Then you go to the full-wave rectifier, always a bit hard to understand, but the flow is very visible in this one and makes it clear:
http://www.falstad.com/circuit/e-fullrect.htmlAnd if you combine the full-wave rectifier with a capacitor, you will understand the basics of how a (conventional) AC to DC voltage supply works:
http://www.falstad.com/circuit/e-fullrectf.htmlSomething more:
Schmitt Trigger:
http://www.falstad.com/circuit/e-amp-schmitt.htmlThis is used f.i. on trackball inputs. The signals from the LED's are not "clean" enough for further processing in the digital circuits of the game PCB, so that's why a Schmitt Trigger is used to "clean" the signal (so that is either high or low and nothing in between.
You can see on this that the high frequency (1 kHz "noise") is of almost no influence on the output signal.
You can also see that the Trigger "Flips" at exactly a certain level of the input low frequency (40 Hz.)