Why are electronic clock mechanisms so fragile?

[IanB]

I've read before that letting the battery run too low can damage a clock (a typical garden variety quartz mechanism as found in most clocks).

Well today I had a different experience. I tried to measure the current consumption of a clock I really like, and maybe I fumbled a bit inserting the break in the battery circuit for the meter, but before I knew it I found the clock no longer working. As far as I can tell the electronics are fried inside the mechanism. The second hand doesn't go and the alarm doesn't beep. All that happens is the clock makes a forlorn scratching noise out of the alarm buzzer every few seconds.

Anyone know what gives? Is it because the electronics are made so cheaply they can't withstand a bit of noise on the power supply?

[MK14]

This seems to look good:
http://www.wikihow.com/Maintain-a-Battery-Powered-Quartz-Wall-Clock

[T3sl4co1l]

They probably don't bother with ESD or reverse protection.  It's sealed inside a plastic enclosure for years at a time, why bother wasting whole cents on that?

Speculation is about all we can offer (unless someone happens to have direct design experience making the chip used inside one!).

Tim

[IanB]

Yes, I understand about the speculation part. I'm just letting off steam really.

It's extra frustrating because this particular clock is not available in the USA and now I have to pay international shipping charges to get a replacement. It's only a few bucks but I hate it when perfectly good things get trashed because one tiny little part has failed.

[amyk]

There are several different types of mechanical clock movements that can be called "quartz", is this the stepper-motor type? As long as the motor coil(s) are still OK, it should be possible to replace just the IC (salvage from another cheap movement) or even make your own...

[Assafl]

I never saw a fried one. Almost always a contact.

The last 10 years they did away with soldering. It is all little pieces of chrome plated metal held against other pieces of metal. Any wiggling of the body can get one loose.

Try rebuilding it. It may still work (as long as the coil is intact as amyk stated).