This will probably be long winded and sorry in advance. I have been programming since the 70s but it has become very apparent to me that I am an extreme n00b when it comes to electronics.
I'm an older dog and have a son in high school who is showing interest in electronics. He is thinking he might want to get into electrical engineering when he moves on to college. The first thing I thought of was to get him an electronics learning lab from Radioshack. I hoped this would give him the basics and give him an idea if this is something he would really want to pursue Actually, I have always been a little interested in electronics myself but have been too lazy to learn. I thought this would be a great excuse to learn a little something myself. It's always been in the back of my mind that it would be great if I had the knowledge to build/invent hardware that I can program to do something.
Well, one day my son asked if I would buy him a programmable microcontroller and I said "sure, just find something you can program under Linux and I'll get it for you" (been 100% Linux at home for the last several years, currently running FC6 on everything). He told me he already had one picked out and pointed me to the Arduino. We got the USB version a few days ago and have been having a lot of fun programming it. We were also into R/C airplanes and trucks for a few years so we have lots of transmitters, receivers, servos and other hardware that will come in handy. I was able to set up some basic circuits to control a couple of Hitec servos using a potentiometer, motor circuits, various led programs, communicate with a running program via USB cable (serial read/write), ran through most of the examples, etc.
It has become frustratingly obvious that I am an extreme n00b when it comes to understanding basic electronics. My first electronics project prior to this was to build a simple IR receiver for my MythTV box a couple of months ago. I didn't actually need one as my PVR card came with an IR receiver and remote but it was a cheap learning experiment. I was surprised when it actually worked when I finished. We have also gone through the RadioShack learning lab books which gave us the basics on how to use a breadboard and some of the electronics basics. That is, I can identify parts, hook them up on a breadboard according to a schematic, etc. I would like to progress into more complex circuits but feel I need more work on fundamentals.
For instance, last night I hooked up a digital pin to the speaker on our learning lab and played music (PWM signals) through the speaker. It was fairly loud and I didn't want to wake anyone up so I threw a couple of resistors between the digital out and the speaker and it quieted things nicely. So then I thought I would just hook up one of the potentiometers and use it as a volume control instead of hard coding a volume with resistors. It did work but for some reason it wouldn't go to full volume as when the digital pin was connected directly to the speaker. It would only go to about half volume. I realize now that these potentiometers have 470 ohm "protection" resistors built in which probably explains why the volume is low and explains some quirks I ran in to in a couple of other experiments. I was expecting to be able to run the pot to 0 resistance and get full volume from the speaker.
I had one experiment that was a complete failure where I attempted to hook up a spare IR receiver module to one of the analog pins for input. I was hoping to be able to detect the signal from a TV remote control. I thought this would be simple based on my IR receiver circuit I had built previously. Nope, wasn't happening. There are a few other simple things I would like to be able to do that are probably very basic but I just lack the understanding.
So here I am. Where do I go from here to learn more about electronics and get enough of an understanding to be able to build my own circuits and really understand what I am doing. Any good resources on the net that you can suggest? We would like to have enough understanding where we can design and build some basic robotics. I feel I might be able to contribute something eventually, especially on coding ideas. Sorry for being long winded on my first post and I promise all future posts will be much much shorter and to the point. Appreciate any advice you can pass along in advance!