screen current

[C Moore]

I thought the term Current was defined as... the flow of electrons.

Then there is:
Conventional Flow (i guess you can call it current if you want)
and
Electron Flow
Those two terms are only a discussion of Polarity/Direction.

Neither of them own the physical part of electricity.....Current/Electrons.
They do not own the word "Current".

But maybe i am wrong.?
95% of you guys know 100% more about this stuff than i do.

[martin manning]

Current is the movement of charge. If you want to assign a negative or positive potential to the charge carriers that is your choice, and circuit analysis is equally correct either way. Most of the world's engineering analysis is done using conventional current where the charge carriers are positive.

[tubeswell]

The reason that we have convention, is to try and avoid confusion. LoL

Strictly speaking, electric current is the rate of change of electric charge. (Not a flow of electrons). It is a scalar quantity. Merlin Blencowe covers this very well in his latest tube amp book.

Indeed, other things besides electrons carry charge (e.g., protons, positrons, etc). Therefore, the vector direction of electric current can be defined with respect to either positive or negative charge. Newton happened to call it positive to negative. YMMV

[C Moore]

Regards to what we are discussing in tube guitar amps.......What ARE the charge carriers.?
Is current flow taking place because something is being "boiled off" the tube cathodes.?
Or is that all just a simplification to accommodate a basic understanding of tube function.?
Thermionic Emission..... Is there something besides electrons being emitted, in vacuum tubes, in a guitar amp.?
Thank You

[martin manning]

the vector direction of electric current can be defined with respect to either positive or negative charge. Newton happened to call it positive to negative. YMMV

Current is a scalar, whose sign can be defined with respect to positive or negative charge. It was Benjamin Franklin who assigned positive and negative... see above.

[TUBEDUDE]

Electrons are boiled off the cathode coating , generally electrons are considered to have a negative charge and drawn to a positive charge.
But you can just as easily describe the action of "current flow" as positive charge moving in the opposite direction.
For each "negative charge unit" moving in one direction an equal "positive charge unit" must move in the opposite direction.
Whichever you feel most comfortable with, is the best way to visualize it.

[tubeswell]

the vector direction of electric current can be defined with respect to either positive or negative charge. Newton happened to call it positive to negative. YMMV

Current is a scalar, whose sign can be defined with respect to positive or negative charge. It was Benjamin Franklin who assigned positive and negative... see above.

Quite right.