Flashing first digit

[digibloke]

Does anyone know what causes this to happen...

On a Quartzmatic watch I have, when I press the time command button the first digit flashes up the tens of minutes number. For example if its 2:15 then the digit before the 2 will flash a 1 for a fraction of a second. (In running seconds mode the first two digits show the tens of minutes like on a bulova driver).

It's working fine apart from this and I've had the display off and on again to check for a short so I know its not that.

It's probably a logic thing isn't it?

[rewolf]

Does the digit flash with normal brightness or brighter?
If brighter, it could be a "stuck" digit multiplexer.
If not, it's probably the logic that selects the digits to display depending on mode, a weak or defective transistor selecting the wrong digit at first. Anyway, this would both be chip-internal.

[digibloke]

If anything I'd say it's not as bright - but it's only there for a tiny fraction of a second so it's difficult to say.

It's a pity as it's taken me a while to get it running but such is life...

Into the spares box with it and on to the next one