Yes you can still test it with just one adapter although it will be a little tedious. put the non adapted battery in first and try to center it up with a little toilet paper or somehting to center it up as best you can then put in the one with the adapter. This should satisfy the edge contact that the F uses. Then put on the cap and try it out. It may take a few times to get it right. But if the meter has life in it, it should at least do something. As for accuracy, I'm guessing the readings will be a wee bit on the underexposure side--maybe 1/2 stop off, but nothing drastic. Im betting the meter is fine. If not, it will have a very good and caring home with me. I like restoring these things. Good luck.