:Jerry: wrote:

AIUI the LEDs, within the common housing, do the 'steering', depending
on which tail is ve+. Also there are tri-colour LEDs which emit their
third colour when supplied with an AC supply rather than DC.

No, that is still a bi-colour - the AC just flashes each "side" in quick
alternation allowing the eye to integrate the colours. A true tri-colour
LED has three leads allowing both sides to be lit in parallel.

--
Cheers,

John.

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