You will be fine with that part. Ed sells the part with the -D suffix which has the same pin out. It has an internal pull up resistor like the 1811 has and a slightly bigger delay but that doesn't matter. It trips at about the same point as the 1811 (5V minus 10%). Sometimes I use a Dallas DS1233-10 which has a different pin out; it has to be installed at a different spot but that one works fine too.

Marco

Thanks Gerry, nice to hear. And you can't go wrong with buying from Ed, he knows where he is talking about and what he is selling. I am currently working on some updates for the testroms. For system 80, you can test all the parts connected to the RIOTs, you can attach a driverboard now and test that as well. The Williams system 7 testrom has now support for Hyperball driverboards. I am doing some more testing at the moment and I am busy with updating the documentation.