http://ebay.to/2aOwSu2 ...and: it´s sold!!! Originally it should have been a 8225 / 30CH / Nonius. rgds - h.u.
One version of the Longines fly-back chronograph had a single button, and used the Longines 12.68Z movement. On the caliber 12.68Z version, both chronograph register hands were centre mounted. I sense a trace of derision regarding this current eBay offering! It doesn't resemble in any way the 12.68Z version I refer to. Appears some of you know something about the eBay item that I don't know.
It is a wretched franken, rendered pointless by the chopped dial. The second hand is beautiful in its own nerdy way, offering 1/10th second accuracy. It just doesn't work without the appropriate markings on the dial. Here's a a graphic representation of how it should be used: The original post from which it was taken is here: http://www.iconeek.com/longinesnonius.html
Correct. like a sliding caliper: So it´s 1,53 cm, not only 1,5something. It´s a nice trick to get a little bit more accuracy using a kind of optical illusion. Longines sold two types of "nonius"-chronos; one using the 30CH (Ref. 8225; parts of this reference were used to build the ebay-franken above), the other with Valjoux 72 (ref. 8271): rgds - h.u.
Although this was a cool marketing trick, it was not actually able to gauge up to 1/10 second accuracy. This is by virtue of the fact that the movement only beat at 18000 beats per hour (5 times per second). The hand was inspired by Longines' timing pocket watch line, which was equipped with a high beat movement, ticking at 36000 beats per hour (10 beats per second).
I have begun to wonder how the subject watch could be called a "fly-back" chronograph! The Longines fly-back chronograph I referred to in my previous post has a single button. When that button is pressed, the chronograph immediately zeroes itself and starts to count again, automatically! The original owner used it for auto rallying back in the late 1940s. For that purpose, the fly-back feature was ideally suited. It appears to me as though the watch that is the topic of this thread, doesn't fly back when the stop button is pressed.
You are correct. However, the operation below does occur when the chronograph is running and the reset button is pressed. Here is a great video of the caliber 30CH operating, by Al.
The watch in the video was actually my own! I especially asked him to take the video for me so that I could watch it operate whenever I wanted to, without opening the back. It seems it's been a joy to many others. Thousands of watches on Youtube and shared many times on the forums.
I seem to remember reading that this one was yours. The video is very useful for understanding chronographs and the fly-back operation. It is also just fantastic to watch the 30CH in action. I have linked the video multiple times as it seems to answer a multitude of questions quite succinctly. Thanks for prodding Al to make it!
It's an Aquastar Deepstar that could have been worth several thousands. Kinda ironic that they ruined such a valuable watch associated with Cousteau.
Thanks so much for sharing that! I got a look at one of these Vernier-scale Longines a few months ago, and wondered what was up with it. Fascinating to know that it's a gimmick!