ESA 942.711 Chronograph

[quietman]

Couldn't find operating instructions for this movement online (Parts List - Yes, Instructions - No).

So can someone enlighten me, in particular how to activate and operate the chronograph function?

[charger105]

From memory, to enter chronograph mode, press the lower left button 3 times in quick succession.
To start/stop chronograph, use top right button.
(To reset chronograph use lower right button.) Correction.....simultaneously press upper right and lower left to reset chronograph.
To return to time-keeping mode, press the lower left button 3 times in quick succession again.

Rgds.

[quietman]

Thanks, thats what I thought.

Is the chrono a particularly flaky part of this module? For some reason I keep buying this model with all functions (including the backlight on the lower left button....) working flawlessly but 'nil points' in the chronograph column

[charger105]

I reckon they're a bit flakey in general.
I've never seen the nil chronograph problem before though

[peachykeen]

Is the chrono a particularly flaky part of this module? For some reason I keep buying this model with all functions (including the backlight on the lower left button....) working flawlessly but 'nil points' in the chronograph column

Welcome to the club. I have the very same problem with all 5 of the modules I own.

[Adam]

The manual can be downloaded from here. I uploaded it a couple of years ago.

http://www.digitalwatchlibrary.com/DWL/ ... er-quartz/

regards


Adam

[quietman]

The manual can be downloaded from here. I uploaded it a couple of years ago.

http://www.digitalwatchlibrary.com/DWL/ ... er-quartz/

regards


Adam

Unfortunately ESA didn't put actual Operating Instructions in these Manuals. They're OK for disassembly and parts identification but not for button guidance.

[Adam]

I think thats the guide you gave me to upload Quietman I must have over ridden the one I uploaded that came with that watch although I never checked for instructions. I'll see if I can find the original.



***UPDATE Fixed you can now get both.

Adam

[dutchsiberia]

All of mine seem to work great, only the backlight on the Certina is very dim. I made sure the button contacts are spotless, because of the need to press three times to engage the chrono etc.

[quietman]

Thanks for all the info. I was kind of hoping that I was just doing something stupid but seems I just have a couple of flaky modules. Fortunately I have a couple of NOS Circuits on the way ..... Lets hope their NOS Working rather than NOS Faulty.....

[quietman]

Well I finally got round to looking at these 942.711 modules properly and it seems there are details in their design that makes it quite likely for the Chrono select to fail in what are now older watches. I thought I'd share my findings with the DWF Hive-Mind.....

The two modules that I had with this fault were both clean to look at from the front and back - no corroded tracks and no battery-juicing evidence. Thats not to say that they hadn't been left with old batteries in them at some stage - but if they had it hadn't been bad enough to take the plating off the battery contacts. Anyway, I think thats academic as the fault perhaps develops whilst the watch has energised batteries..... Or perhaps worst case - energised backlight battery and flat watch battery.....

Popping the mirror assembly off the front of both of these PCBs revealed immaculate wirebonds and tracks - all except for (in both cases) the Chrono select track which on one looked very slightly tarnished and on the other looked almost black. On the better of the two the wirebond to track junction was a little bit 'furry'. On the worse of the two the entire Chrono select wirebond had been consumed into a hairy white monster.

The Chrono select line is shared with the BulbV- line. The rest of the watch (well most of it) sits not more than 1.5V above the case voltage and this Chrono select line sits not more than 1.5V below the case voltage - it is the most negative node in the module. The chip cover/mirror holder is not sealed at all - there are loads of open vias running under. Also, there is no solder resist on the chip-side tracks

If one was to take a stab in the dark at the wirebond material being an aluminium alloy (visibly white metal -> white metal salt) then it might happily react over time with relatively low levels of airborne electrolyte vapour. Selectively driven by the low static voltage on this node when the circuit is energised and in preference to other parts of this node due to the more negative (galvanic) electropotential of the wirebond material.

Nurse says its time for my medicine

[charger105]

Nice detective work.
If I get one of the non working chrono modules, I'll check to see if this wire-bond shows the same degradation.
Were your NOS circuits NOS-working or NOS-faulty ? I just received 4 of the same but haven't had a chance to fire them up yet.
Rgds.

[quietman]

Were your NOS circuits NOS-working or NOS-faulty ?.

One working and one not. Thefaulty one has a (too) low impedance oscillator input on the IC. The poor little Xtal can't wobble hard enough.

I only needed one worker but they were cheap-ish, so buying two was a bit of a pragmatic hedge in the first place. Still, can't help wondering - if I'd bought one - would I have got the worker or the non-worker?