More likely than not this is a slave clock powered by a 24VDC reverse polarity using a Lavet-type stepping motor movement<https://en.wikipedia.org/wiki/Lavet-type_stepping_motor> made by mobatime of Switzerland controlled by a master clock - I would open the case and see what the movement marking are - some are 12VDC some 24VDC and some switchable. We make the same time of master clock, after the clock is initially set - the master clock remembers the position of the impulse clock - I believe the reverse polarity type of movement was developed due to problems with double bounce relay contact on the master clock. An H-bridge would also run this or to test the movement just apply 12VDC or 24VDC and to the movement and alternate for the next pulse. Thomas D. Erb p: 508-359-4396 f: 508-359-4482 a: 97 West Street, Medfield, MA 02052 USA e: tde@electrictime.com w: www.electrictime.com Tower & Street Clocks Since 1928