Bulova N6 with mostek module.

[digibloke]

I've got a couple of bulova N6s (one of my favorite watches) with an annoying problem. They work great for anything between five minutes and a week then go stone dead. They come back to life after a day or so without batteries - then go dead again.

I've checked all the contacts (thought it might be the nasty battery connector wandering about) but they're fine. I've checked that the quartz x-tal isn't shorting (why'd they use such a massive quartz case right next to the battery connection?) again fine. My best guess is a failing x-tal but I always prefer to try simple solutions before getting my soldering iron out...

Is there something I'm missing or does anyone know of any regular faults that show up on these modules. It's the same as this one here by the way...

http://www.ledwatches.net/photo-pages/imado1a.htm

Any suggestions greatly appriciated. DB.

[dot matrix]

Any possibility that the rating on the batteries you're using is slightly off for the watch?

[digibloke]

I don't think so. I'm using AG12's which I belive are the same as 386's (as suggested on the inside of the caseback). I've also had a try with silver oxides, but again - no dice.

Is there anything closer to a 386 than an AG12?

I've got an Imado with the same module and it's one of the best time keepers I've got. Slightly different display though and nowhere near as bright.

(It's much brighter at the moment though given that the bulovas aren't lighting up at all).

[Majestyk]

When one of them goes dead, don't open it and get a blow dryer or a heat gun (a good distance from the watch) and then after it gets fairly warm, then try it. (Watch you finger if the button is too hot). Or stick it up to a 100+ light bulb for awhile.


Jeff

[digibloke]

Certainly worth a try. I fired one of them up this morning - for some reason they seem to be more inclined to start if I take the three pieces of module apart then put them back together again (red plastic front, circuit board and back). Anyway it was running great when I left for work and I'll try the hairdryer when I get home tonight (when it will no doubt have gone to sleep again).

[digibloke]

Hi. Got back from work to find it as dead as a dodo and tried heating it up to finger burning temperature. Nothing I'm afraid.

I've had the modules apart and when they're in their none-working state they won't fire up on an external power supply either - so I can rule out a problem with module to case connections.

They only seem to come back to life after several hours without any power in them (they stay dead if I leave the batteries in).

Still wondering whether it's worth replacing the quartz on one of them, but I'll wait a while to see if anything else comes to mind first.

Think I'll go module shopping in the meantime just in case...

[digibloke]

I put a new quartz oscilator crystal onto one of them at the weekend. It fired up straight away, ran for about 4 hours. Then went dead.

I give up.