I picked up a nice Zeiss Ikon 6x9 yesterday. I checked out the shutter and found that it was working great even at the slow speeds, but of course the my eye is not calibrated. I noticed the small button on the top of the compur shutter, and began to play with it trying to figure out what it was. I cocked the shutter and discovered that it could be cocked further if the button were was pressed, but then when I clicked the shutter it didn't fire. Now it is jambed! Yuck. After internet research I learned that the button was a self timer that often never works. But now I can't figure out how to get the the self timer off, and the shutter to fire normally. Any body know what I need to do to unjam this Compur?