Junghans J68, updated 04.01.2020
Junghans
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Timing watch
1932 - 1937 (1945)
Open face
J68
20'''
41,4 mm
7,8 mm
1/5 sec. = 18000 A/h
1/10 sec. = 36000 A/h
U423/2110
W1819
Nr. 1030:
390 x 2,1 x 0,17 mm
Jacob 1948 page 41
4
38 g
92 g
53 x 74 mm
108/51, 108/52, 108/53
108/56
The production time is confirmed only until 1937, 1949 the J68 is not mentioned anymore in a catalog or pricelist. In the "Marine Dienstanweisung Nr. 2456 - Zeitmeßgeräte der Kriegsmarine" from January 1945 the J68 is mentioned with it's group index number 108/56 - f) Stoppuhren 1/5 Sek. (Zifferblatt mit 1/100 Minuteneinteilung), Fabrikat Junghans 108/56 - which implies that the J68 was built until 1945.
Based on the J29 movement the J68 fits into J29 cases and vise versa. Also the dials will fit on both movements. Difference between the 1/5th and 1/10th second registering movements is the balance wheel which is much more massiv on the 1/10th version.
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108/52 Registering 1/10th seconds
108/53 1/100 minute divison
This should also be the 108/56 according to the Marine Dienstanweisung Nr. 2456 - Zeitmeßgeräte der Kriegsmarine" from January 1945, registering 1/5th seconds with a 1/100 Minute division.
Later once have a extra stop mechanism for the center wheel.
This J68 has no Junghans trademark on th movement.
The following pictures are courtesy of F. Fügemann and showing a J68 timing watch for the German Navy.
On the dial you see a special artillery telemeter with hm unit, hm = hectometer = 100m, EU = Entfernungsunterschied (distance difference)
J68 copyright F. Fügemann
J68 copyright F. Fügemann
As this seems to be a late version of the J68 with its serial number 91286 some design changes are present. First the J29 balance wheel is used and the center wheel stop was changed.
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The following pictures are courtesy of F. Fügemann and showing a artillery-J68 timing watch with the center wheel stop function.
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Left the 1/5th second balance ring.
Diameter 15,5 mm height 0,74 mm.
Right the 1/10th second balance ring.
Diameter 15,5 mm height 0,37 mm.
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The following picture is courtesy of Thomas Fiolka showing, what we consider, a prototype of the J68 derived from the J29a.
J68 Prototype
A handy hint by F. Fügemann was the Bergeon Presto 4 tool which makes accident free hand removal possible.
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