Hi John,
Your memory is correct about electrons flowing from negative to
positive. They still do. However when analysing transistors it is often
easier to look upon the electron flow in one direction as being "holes"
(or "places where an electron could be but isn't") flowing in the other
direction.
Thus we have come round a full circle, because 200 years ago when
scientists had no idea what "current flow" was, they arbitrarily decided
to state that "current flow was from + to -", a convention we still use
today.
I hope this doesn't make confusion worse confounded.
My comment about "what other polarity was there?" was meant to indicate
that almost all practical designers up to the 1920s and early thirties
just accepted the convention and allocated ground or earth to negative.
They didn't think it important - and why rock the boat?
It's interesting for me to learn that White Truck's designer had a mind
of his own. Many thanks for the info.
Cheers ..... Pat
"John T. Seim" wrote:
>
> With respect to what other polarity was there to use in the early
> thirties, I have a White truck, produced in Cleveland, OH, in 1930, and
> it was positive ground.
> If my electronic schooling memory is correct, the electron flow theory,
> depending on who wrote the textbooks, used to conclude that electrons
> flowed to the positive. It was later found that electrons flow from
> positive to negative, hence the wiring and earthing changes flip-flopped
> between positive ground and negative ground.
> John Seim
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