The Dilectron is a very ingenious use of electronics in a clock. An electrically impulsed moving magnet balance wheel is the timekeeper, but it is totally free-running, and has no physical connection with the gear train unlike other moving magnet clocks shown on this site.
The pulses from the balance coil control the speed of a separate electric motor which drives the gear train of the clock.
The moving magnet balance, at the top right, vibrates at 48,000 cycles per hour, (800 per minute, 13.33 per second) which is a very high rate for a balance. The motor coils are visible through the six holes on the left of the circuit board.
The motor consists of a vertically mounted cylindrical magnetic armature, with two north and two south poles diametrically opposite each other, and a coil assembly consisting of three windings that covers only half of the armature. The armature revolves at 400 r.p.m. and is effectively a synchronous motor governed by the pulses from the balance. A worm drive (just visible below the coils) drives the gear train.
A fuller explanation of the electronics is given in "Britten's Watch
and Clock Maker's Handbook & Dictionary", published by Methuen - ISBN
0 906 22389 X
