|PO ENGINEERING INSTRUCTIONS
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.
CLOCK No. 82A
Double sided clocks with 12” dials for use in public office windows. The clocks are suspended by conduit. These are
Clocks No. 76A mounted
back to back on a central ring.
PO ENGINEERING INSTRUCTIONS
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.
Clock No. 82B
Double sided clocks with 12 in. dials for use in public office windows. The
clocks which are suspended by conduit,. consist of Clocks No. 76B mounted back
to back on a central ring.