"So basically PWM is just a digital way of turning a voltage like 12 volts into any voltage from "
Yes and no. PWM-DC really should be thought of as an AC form of voltage, since the waveform is quite variable and in most ways it can't be treated as "plain" DC at all.
Like, the
radio interference problem, akin to AC not DC.
Like, not being able to accurately measure or meter it, akin to changing AC waveforms, not "plain" AC and not DC either.
" it's just the way that processors create a specific voltage from a higher voltage. "
Yes, but that's not critical. What's important about PWM is that it allows processors to work the OTHER WAY AROUND, boosting lower digital voltages to higher ones as well, and to change voltage WITHOUT DUMPING POWER. A plain DC regulator can reduce voltages just fine all by itself--but the PWM system does it without dumping power (net wattage), making it more efficient, if more expensive.
And, there's that effect on battery charging. Apparently well documented and confirmed by reputable parties--but someone forgot to tell us plain folks.
"Stereo systems could use PWM to create the voltages necessary to reproduce music on speakers, but it would sound like crap," Well, haven't you just described the CD player, MP3s and digital music? They all start with a digital signal, quite similar to PWM-DC with a uniform pulse width and only the rate varying. Matter of fact, that's almost identical to a classic automobile alternator putting out PWM-DC using a fixed pulse width, like a classic Delcotron. OK, it gets converted back to an analog signal before we hear it--but there are folks who still say it sounds like crap because of conversion issues.
I tried to get a look at the SolarBoost output on an oscilloscope, an older Tektronics model. If I really pushed things....I got something with a fairly regular waveform, but I have no idea how badly the battery was swamping things, or how that really could have changed once it got outside the bulk acceptance charge. It was a tall square wave with a sloppy bottom corner, which I assume was the result of an inductor "dying" in the end of a discharge cycle. One of those "yeah, but it really doesn't matter, it works just as well and is cheaper to build that way" things. Not worth speculating about.
Cam-
Although I was in the bulk charge phase...is it possible that I would have seen more amperage out of the controller IF the batteries had been discharged? Maybe it was giving me higher voltage and less amperage, because that's what the battery needed more in the existing charge state?
One more thing to test, next time the rain gods and the sun gods all conspire and the tornado warnings stop long enough for me to spend some quality time with a good book...and some electronics?