After 30 years, man, it's like... well, hope springs eternal.
So, here's a "poster" (Take this, may it serve you well) ─
Hey, I'm only 51!
Anyways, part of why I'm messing with this stuff is to engage (or re-engage) my gray matter. I could point to lots of people who maintained mental acuity into advanced age. I do have hope.
Thanks. I will endeavor to understand those. Suppose, despite:
(although the posting I originally referred to is about how/why transistors WORK, internally as a semiconductor, not about how they BEHAVE in circuits.)
, stay on topic?
that we attempt to examine that common collector voltage regulator, in terms what free_electron wrote over at EEVblog:
If i am not pulling anything out of the base i have those two darned depletion layers in the way that prevent current from flowing. if i start pulling some electrons out of the base the depletion area is being broken down
So, once the capacitor is fully charged, there will be no base current to "pull electrons out". I have to assume that there's a return through the load which keeps some base current flowing there, so I guess the cap is just for smooting out ripple.
Now he also writes:
If you read mine attentively you will see that i never use the word 'base current'. It is the voltage difference ( potential) that causes the electrons to flow , and the electrons are charge carriers. it i indeed the pressure ( the 'voltage' , technical definition 'potential' that cases charge to move ) i control the direction it is allowed to flow by applying pressure ( or void thereof ) to the base
even though he did talk about base current. Well, I think electrons flowing is current. So anyway, I see this as the load being parallel to Vbe and Vz, with Vbe (i.e. the junction voltage) in this context being -0.8V. As the resistance, or impedance, of the load decreases, then the base current would have to increase, in order to maintain 6V by allowing more Ice to flow.
I initially thought that R1 was supplying to current to D1, in order to develop the 6.8V there, but now I have no idea. ETA:
I did some more reading. R1 is there for bias?
There. How's that?