Mr Simple Q, I see your point about the "minus half of the signal" but I don't apologize for misinterpreting such unconventional and confusing terminology. When most everything else he said was wrong it was only logical to assume that this was too, and it is in purely technical sense i.e. his statement made no sense. In 25+ years involved in electronics I've never heard that terminology. Make that statement to any electronic engineer or technician and they will have no idea what he is talking about.
As for current, it is indeed the flow of charge. It does not have to be electrons and slow drift speed is a reality as stated. Do a little googling for a more complete explanation.
Garch, I got your email. I do not care to debate you here or via email on a subject you clearly don't understand.
Mr Romgard, sorry for getting off track here. To answer your original question, there is no standard for this so there is no set answer. Some cable designers intend the arrows to point one way and some the other.
Amazing what such a simple question will bring out.
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