merithew@jessica.stanford.edu (Robert Merithew) (08/31/89)
I recently acquired a 1982 Audi 4000 with an analog in-dash electric clock that doesn't quite work. It apparently stopped working after a catastrophic electrical system failure some years ago. It seems that the clock motor pushes the second hand backwards every alternate second (quite amusing to watch, but rather useless as a clock). The clock takes 12V DC and consists of a couple of capacitors, a resistor, a crystal, a magnet coil around a couple of pieces of metal that form the motor, and, of course, the inevitable mystery IC from Germany. My question: How might such a clock work? Anyone recommend a book that might explain the theory of operation of such a clock? of electronic clocks in general? Anyone have any guesses about the mystery IC? (I can't read the back of the IC without heavily damaging the clock, but I haven't really got anything to lose...) I called an Audi dealer, and (much to their amusement) discovered that ordering a replacement clock from VW/Audi would cost me at least $160. (must be a pretty special IC!) I'll probably just slap a $2 stick-on clock on my dash anyway... I was just curious about how quartz clocks work. -Robert Merithew merithew@jessica.stanford.edu (internet preferred) MERITHEW AT SUWATSON (bitnet)