Hereís a new one:
Got my NOS Longines VHP (L174 movement) and for a month or so it ran great. Then I noticed a few seconds shaved off. Then I got a few stops and starts. And then, incredibly, I would notice the second hand spin or shudder, sort of attempting to catch up when it would stop. Sometimes a bit of a tap would cause this, otherwise, totally random. Had he battery taken out and replaced and seems to be keeping time, but the first time it lost seconds it took weeks. And Iíve been nervous to wear it. Definitely reacted to minor impact from my fingers tapping on the crystal.
Battery tests fine, and my watchmaker says the circuit is carrying voltage correctly, that it may have been an improperly seated battery, which I find to be a questionable hypothesis. If it were a mechanical watch, Iíd say this is a balance-wheel issue, but on a quartz movement, Iím thrown for guesses.
Anyway, do any of these symptoms correlate to a specific issue endemic to these HAQ movements? Or is it just a 30-plus-year-old movement that will either need a replacement or service? Could it be a magnetism issue or other non-invasive problem?