I tested the SN76489ANs I bought last October. Unless I'm doing something very wrong, they seem to be fakes. Disappointing, since I was hoping to add one to my 6502 computer this weekend. I ordered a handful more from a top-rated eBay seller, but it'll be at least a couple weeks until they arrive.

@daremo Ouch. Are they just not responding to bus transactions? Any possibility of damage from static?

@vertigo Audio Output pin stays at a ~1V waveform on power up and after I write to the bus. Should be a square wave, but it looks like a sine wave with inconsistent frequency (haven't dug into that). They all do this. I used a grounded wrist strap when I installed them into the breadboard. I can't think of another time since I received them they could have been damaged by static. I welcome any other ideas.

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