I recently inherited one of these and I'm not sure what to make of it. It doesn't seem to have any shutter speed adjustment besides a 'bulb' option, and I can't make out any aperture adjustment either. It has guess focusing and takes 620 film--there is a 620 spool inside. I would consider ordering some 120 film and using it just for fun but how do you get proper exposure?
You might want to hunt up another 620 spool. I don't know if this camera will accept a 120 spool at either end, some do, others don't. With two, you'll be sure it works. Re-spooling 120 onto 620 spools isn't difficult. I managed to do it first time in the dark with no problems. With a sacrificial roll, it's a lead pipe cinch.
Getting to this late... This is indeed a fine little camera. There is a waterhouse type F-stop arrangement. You pull out the little tab at the bottom of the camera as it is held horizontally. This site http://licm.org.uk/livingImage/Jiffy.html gives the stop sizes. Shutter should be about 1/25 or maybe a little faster.
I cleaned out the lens on mine and had to adjust the viewfinders to make them frame right. It takes fine pictures of the old-camera soft-focus type.
You have to re-roll 120 film onto 620 spools, but that is not too difficult in the darkroom. There are threads here that tell how to do that.
I'm not sure how valuable these are. I paid $35 for mine a couple of years back.
Have fun with it and take some pictures with the lens before you make it into a pinhole.
Its funny but I never thought to try that trick. I just pulled it out and tried a scrap roll of 120. It feels a little snug, but it will probably work. You may want to try it.