GPO WATCHES


P.O. ENGINEERING DEPT.
ENGINEERING INSTRUCTIONS
MISCELLANEOUS
TIME
B 1201
Issue 6, 12.12.60

WATCHES

1. General
This Instruction gives general in formation regarding the watches used by the P.O.


2. Uses

  1. Watch No. 1 should be used only on duties which cover the maintenance of clock systems.
  2. Watch No. 2 should be used where a stopwatch facility only is required, e.g. for general telegraph timing purposes and in schools.
  3. Watch No. 3 should be used for traffic recordings, etc., where it is necessary to measure two or more intervals of time concurrently.
  4. Watch No. 4 should be used primarily at overseas exchanges with Stands, Watches, No. 4, but may be used elsewhere where only a stop-watch facility is required and a Watch No. 2 is unsuitable.
  5. Watch No. 5 should be used for timing requirements on power plant and for postal duties.
  6. Watch No. 6 has been used in a limited capacity for traffic recordings, observations, etc. It is obsolescent and further purchases will not be made.

3. Provision
Watches should not be issued permanently to individual officers but should be held in the Area plant list and issued when required. The issuing officer is responsible for watches being in good order and for returning surplus watches to the Supplies Dept. A few Watches Nos. 2 and 5 (in working order) may be held in each Area for replacement purposes. The method of requisitioning watches is dealt with in STORES, General, F 0071.

4. Care to be exercised in use
The watches are of a high-grade type, as robust as possible, but they will not stand rough usage and should be treated carefully.
Watches have ‘hinge’, ‘snap’ or ‘screw’ type backs, but identification of the type is not always easy. If in doubt, always try unscrewing first, in an anti-clockwise direction. Insert a penknife to remove ‘snap’ tacks, or to open ‘hinge’ backs, only when satisfied it is not a ‘screw’ type. Normally Watches Nos. 1, 2 and 3 have hinged backs, Watches No. 4 ‘hinge’ or ‘snap’ type, Watches No. 5 ‘screw’ or ‘snap’ type and Watches No. 6 double hinged backs.

5. Maintenance
Regulation, minor adjustments and repairs such as loose winding buttons, broken glasses, etc. should be done in the local mechanics’ shop or by a watch repairer. Watches damaged beyond local repair should be returned to the Supplies Dept. according to the procedure described in STORES, General, F 0071.

6, Packing
Inserts, Special, Nos. 8/16 and 8/17 should be used for storing Watches Nos. 1, 2, 3, 5 and 6, and Watches No. 4 respectively or as packing for transit.

7. Description.
(a) Watch No. 1 is a 24-hour, high-grade, keyless, lever timepiece with a stop-watch facility of the centre-seconds fly-back type. A minutes register which steps each time the centre-seconds hand reaches the 300 mark is provided at the top of the dial and integrates the revolutions of the centre-seconds hand up to a maximum of 30 minutes. The operation of the stop-watch facility is controlled by a plunger protruding through the winding button. With the main spring tensioned, the first depression of the plunger sets the centre-seconds hand in motion. A second successive depression stops the centre-seconds hand and a third successive depression restores the centre-seconds hand and the minutes register to zero. The illustration shows an elapsed time of 5 minutes 16.4 seconds. The watch has an accuracy of ± 10 seconds per day.

Watch No. 1 Watch No.2 Watch No.3

(b) Watch No. 2 is an 8-hour, keyless, lever stop-watch of the stop-start, centre-seconds fly-back type. A minutes register which moves simultaneously with the centre-seconds hand is provided at the top of the dial arid integrates the revolutions of the centre-seconds hand up to a maximum of 30 minutes. The operation of the stop-watch is controlled by the winding button. With the main spring tensioned, the first depression of the winding button sets the centre-seconds hand in motion. A second successive depression stops the watch and a third successive depression restores the hand and minutes register to zero. The illustration shows an elapsed time of 4 minutes 18.4 seconds. The watch has an accuracy of ± 4 seconds in 8 hours.

(c) Watch No. 3 is an 8-hour, high-grade, keyless, lever stop-watch of the permanent-motion type with a seconds hand, and with two centre-seconds fly-back hands with independent fly-back facilities. A minutes register which steps each time the upper centre-seconds hand reaches the 300 mark is provided at the top of the dial and integrates the revolutions of the upper centre-seconds hand. The operation of the watch is controlled by the winding button and a plunger on the side of the watch. With the main spring tensioned, the first depression of the winding button starts both the centre-seconds hands in motion. A second successive depression stops the hands and a third depression restores the hands and minutes register to zero. With the two centre-seconds hands in motion, the lower hand only is stopped when the plunger on the side of the watch is depressed. A second depression brings the lower hand in step with the upper, and both then continue moving together. This operation may be repeated until rewinding is
necessary. The illustration shows an elapsed time of 4 minutes 46.4 seconds for the upper hand and 4 minutes 21.4 seconds for the lower hand. The watch has an accuracy of ± 4 seconds in 8 hours.

(d) Watch No. 4 is an 8-hour, keyless, lever stop-watch of the stop-start centre-seconds fly-back type. A minutes register which moves simultaneously with the centre-seconds hand is provided at the top of the dial and integrates the revolutions of the centre-seconds hand. The operation of the watch is controlled by the winding button and a slide fitted on the side of the watch. With the main spring tensioned, the centre-seconds hand is set in motion when the slide on the side of the watch is moved in a clockwise direction and stopped when the slide is restored to its normal position. A second clockwise movement of the slide restarts the watch from the point at which it stopped. This operation can be repeated until rewinding is necessary. A single depression of the winding button restores the centre-seconds hand and minutes register to zero. The illustration shows an elapsed time of 4 minutes 47.4 seconds. The watch has an accuracy of ± 4 seconds in 8 hours.

Watch No. 4 Watch No. 5 Watch No. 6

(e) Watch No. 5 is a keyless, lever timepiece without stop-watch facilities. The watch has an accuracy of ± 10 seconds in 24 hours.

(f) Watch No. 6 is an 8-hour, high-grade, keyless, lever stop-watch of the permanent-motion type with a continuously operating seconds hand at the bottom of the dial, and two stop-start centre seconds fly-back hands with an associated revolution register at the top of the dial. The centre-seconds hands make one complete revolution in 100 seconds over a scale marked in half-second divisions and the revolution register integrates the revolutions of the upper centre-seconds hand up to a period of 3000 seconds. i.e. 30 revolutions.

The operation of the watch is controlled by the winding button and a plunger on the side of the watch.  With the main spring tensioned, the first depression of the winding button starts both the centre-seconds hands in motion. A second successive depression stops the hands, and a third successive depression restores the hands and the revolution register to zero.

With the two centre-seconds hands in motion, the lower hand stops when the plunger on the side of the watch is depressed. A second successive depression brings the lower hand in step with the upper hand, and both then continue moving together. This operation may be repeated until rewinding becomes necessary.
The watch has an accuracy of ± 3 seconds in 2.5 hours.

8. Stands, Watches, No. 4
These are intended for use at overseas exchanges and are designed to accom modate two Watches No. 4, large or small, and pro vide facilities for starting and stopping the two watches simultaneously or individually.

 

 
 
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Last revised: February 06, 2011

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