I am fairly sure if he though multiplexing worked in his environment, he´d be doing it.

In my own experience, even overdriven LEDS barely work in outdoor applications when multiplexed.

actually we have one multiplexed, however, it is multiplexed 1:2, not 1:8 or some such.

It dates from the days before my time here when a static (replaceable) display was the standard. Today scroll and such is required and this board is replaced at every customer that wants anything more than a static display.

Yes, you 'can' multiplex a sunlight sign (at least 1:2, I doubt 1:more than that) but the 'side effects' of having to synchronize everything to the multiplexing gives horrendous 'time clots' that virtually guarantees some intermittent malfunction somewhere else.

Erik