I assumed the floating input began to oscillate (as I've read they can do, at least on CMOS which this chip apparently is not) giving the impression that the output was floating. Either way, using 220 ohms instead of 1k fixed it.
I assumed the floating input began to oscillate (as I've read they can do, at least on CMOS which this chip apparently is not) giving the impression that the output was floating. Either way, using 220 ohms instead of 1k fixed it.