CLOCK No's 74, 76, 78 & 80


PO ENGINEERING INSTRUCTIONS 
MISCELLANEOUS
TIME
B 1361
Issue 4, Oct 1970

CLASS B (SYNCHRONOUS) CLOCKS

One of the standard synchronous clocks at present used by the PO. The movements are described in B 1351.

Synchronous clocks are suitable for use only in areas where the mains supply is reliable. The basis for provision is given in B3001. The types used in the PO are all non self-starting for use on a supply of 200-250 volts ac, single phase, 50 Hz, with a frequency which is time controlled. They should not be installed where time keeping is of vital importance.

Clocks Nos. 74B, 76B
General purpose wall mounted clocks. These clocks were specially designed to be suitable for use with any type of decor. The cases are circular, spun aluminium, finished in polychromatic silver/grey. The clocks are mounted by means of mirror plate suspension. The dials are white, with black markings in the hour positions, but no numerals.

No. Overall dia. Dia. of dial Depth (back to front)
74A 9 in 7.75 in 3 in
76A 12 in 10.5 in 3 in
78A 18 in 16.25 in 3.25 in
80A 24 in 21.75 in 3.5 in

PO ENGINEERING INSTRUCTIONS
MISCELLANEOUS
TIME
B 1321
Issue 5, Oct 1970

CLASS A (PULSE) CLOCKS

This is one of the standard half minute pulse clocks at present used by the PO. The movements are described in B 1311.

CLOCKS No's. 74A, 76A, 78A and 80A
General purpose wall mounted clocks. These clocks were specially designed to be suitable for use with any type of decor. The cases are circular, spun aluminium, finished in polychromatic silver/grey. The clocks are mounted by means of mirror plate suspension. The dials are white, with black markings in the hour positions, but no numerals.

Drawing No. P/T 10011.

 
 
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