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Repeater Circuit The 1 sec clock drive from the master can only drive
around 3 quartz clock motors. The repeater above uses a 4093b in a NOT
configuration.
The alternating plus and minus output from the
master is fed into the pairs of gates IC1a&b and IC1 c&d and is
inverted.
Each pair of gates can now drive 3 1 sec clock motors.
Each output is adjusted by a variable resistor to suit the number and
type of
1 sec clock motor. Zener diodes protect
the output from any back emf produced by the clock motor drive coils.

Regulator Clock Circuit
The regulator is built into a 12" office clock case and uses 3 movements
all driven from the quartz motor driver output of the master.
I have used a standard movement for the secs, a high torque movement
for the mins (as the dial is 12") and a 24hr movement for the hours.
All movements have their quartz drive circuitry removed and
connection made to each drive coil for driving from the master.
The clock incorporates a repeater circuit that can drive 6 quartz
clock motors (3 per pair of gates). Extra repeaters can be added as required.
The switches are used to set the regulator in synch with the master.
The seconds hand can be stopped or stepped forward for easy
synchronisation.
SW2 stops the second hand and connects SW1. SW1 is a 3
position switch with centre off. To step the 2nd hand the switch is
cycled
up and down rapidly producing the alternating plus and
minus condition required to step the 2nd hand clock motor.
VR3 reduces the current to the motor and is adjusted
to give a nice step to the motor.
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