Junghans Time Transfer Pocket Watch

Extract from the LDV. 253/6

Description, operating and maintenance instructions of the Air Force watches

Part 6

Time transfer watch ZÜU

Issue 1939, free translation by Dirk Fassbender

 

Usage.

The time transfer watch ZÜU is used to transfer the absolute time of day of the time-keeping master clock (ground chronometer) to the watches of each aircraft. It is set accurately to the second.

 

Device identifier

Manufacturer:        Junghans A.G., Schramberg / Schwarzwald

Shipping company: Junghans A.G., Schramberg / Schwarzwald

Model:                   ZÜU

Request mark:       Fl 23884

Weight:                 0.260 kg

 

Description

Serving to display the time of day are the dial, the hour and minute hands and the second hand. The dial is provided, instead of the usual number of hours, with hour lines, wherein for better readability the lines for hours three, nine and twelve are made thicker and longer than the other hour marks. The hour hand, minute hand, and hour marks are covered with luminous material.

The clock is housed for protection against external influences and convenient handling in a wooden cabinet. To operate the winding crown a housing cover via a hinge to the left is hinged. The closure of the housing is effected by a push button. On the front of the timber housing, a plastic writing surface is integrated.

 

Operating and maintenance instructions

Winding the watch.

Winding the watch follows after opening the housing cover by turning the crown to the right until making a slight resistance is felt. The use of force must be avoided under all circumstances. Left turning the crown runs free. The total power reserve of the watch is 32 hours.

 

Set the pointer.

Placing the pointer on the absolute time of day is made with the crown. By carefully pulling out the crown (to a feelable stop) the winding stem is brought into connection with the set train. Same time, the balance of the clock is stopped by a fine spring. The second hand can be stopped at any second line. By turning right or left of the extracted crown, minute and hour hands can be adjusted to the desired time. Once the master clock (ground chronometer) indicates the set on-time, considering the position error, the crown is pushed back into its normal position and thereby set the clockwork in motion.

 

Writing tablet

The writing surface located on the front of the timber housing may only rewrite with a pencil (not with color- or ink pen). It is intended for recording a time protocol and set of to the clock. The records can be wiped off with a finger.

 

Maintenance and testing

The reliability of the accuracy of the time transfer watch depends on careful maintenance and care. The clock must be subjected to a timing test at least every six months. The timing of the clock (when fully wound within 24 hours) may not exceed above +/- 20 seconds in position dial-up at normal temperature (+ 25 ° C + 15 ° C).

Watches, which no longer meet this condition are carefully packed and provided with an inspection report to the competent Luftzeugmeisterei or special workshop (also repairing front points, provided that they have adequate facilities for watch repair and trained watchmakers) forwarded.

 

Any previous repair attempt by removing the watch from its housing is prohibited.

 

 

 

Page taken from the LDv 253/6 showing the watch inside the wooden case.