Help with a no spark 1978 KZ400

Hi - I've got a KZ400 project bike that I just pulled out of the barn. I've got 12v going into the coils. I checked the points and I get 12v/10v when they open/close. Is it supposed to drop to 0v?

If the above it okay, what's the procedure for checking the coils themselves. (It's a new unit that I got last fall, but worth a check I'm thinking.)?

Thanks in advance.

There are two wires on the coil. One should stay near 12v.
The other wire will switch between 12v and 0v as the points open and close.
Close should measure near 0v.
Open should measure near 12v.