I have just purchased a Nettar 515/2 camera which has a dial-set Telma shutter. All the info I can find about Nettars says they were introduced in 1934 - which seems a bit late for a dial set shutter. In fact, all the pictures of Nettar 515/2 cameras on Google have rim-set shutters.
McKeowns Collector guide says: The Nettar 515/2 had been produced from 1933 till 1951. I have the 1933 515/2 with art deco styled hexagonal shutter front. In 1934 the design changed to Ikonta-style and the early models have Nettar f6.3 or 4.5/10.5cm in Telma. This shutter was still used, amongst others, from 1935 to 1938. Alfred Gauthier in Calmbach (AGC ) invented the Telma shutter for 1/25, 1/50, 1/100 (1/125) sec. in 1926 and a second version for 35mm film (1/25, 1/50 sec. ) in 1933.