The one I have connects directly to the side port (no ribbon cable). The red power LED comes on showing it has power. However, it has, what I thought was an optional, power input for use with speech module. I don't recall having a 5 volt power supply to use with it, but it's worth a shot I guess. When I wrote the original post, I had just PC formatted the CF disk. Since then, I have downloaded the DOS utilities and the sample VOL1.DSK file that goes with it. Still didn't work. Also tried some disk images found here and no joy.
Addendum: The CF card is the original 32MB card that came with the device. So compatibility shouldn't be an issue.