It's electronics, but not as we know it Jim.

[ppppenguin]

This is starting to sound like the old "collectors up" vs "+ve up" debates. In the days of PNP only designs then colelctors up was fair enough. As soon as you mix things up then always +ve up. As for the yanks and their penchant for putting the power rail at the bottom I just don't get it. Perhaps, as the late Gerry Wells said, it might be the "low voltage accents".

[BusyBee]

My take on some of these foreign (US or European) circuits has often been the symbols used for the valves and their layout rather than any position of particular power lines. I do notice a hint of this in the op diagrams with the symbols and particularly labelling of the resistors which would confuse a beginner. As I often use multiple supplies (perhaps the easiest to understand being plus / gnd / neg three rail), I do think a bit. Admittidly it is easier using the common 'standard' with plus at the top, which I normally do.

Tracy

[Mike Watterson]

And re: Positive vs Negative
https://xkcd.com/567/

[ppppenguin]

I routintely use +/0/- rails. So + at top, 0 in middle, - at bottom. Power rails often just marked at point of use.

Example of one dated way back in 2011, though its origins go back a few more years, probably into the 1990s. It's part of a long obsolete design I did for a client.