A few more pictures, now I've fitted a Eulit Barington Ostrich strap, correctly sized at 17mm.
The 830 movement is a bit quirky as pointed out before, and interesting to watch when being wound. Parts have a lovely red-gold hue which I think is copper, although I've read about some having rose gold plating.
Helvetica was part of General Watch Co. in the early 20th C along with Omega so they are cousins way back. That ended long before this watch was made. Here it is with an older brother. A lot changed in 20 years or so.