Re the G-Mix - year setting runs forward to 2039 but the first year that can be set is 2000 which kind of dates it to that year. The tunes available are (Can't get no) Satisfaction, Smells like Teen Spirit, Heartbreak Hotel, New Year's Day and Walk this Way. All in glorious Casio tones - there are two little contact springs instead of one to provide the sound so I assume it is two notes at a time - melody and bass line.
It was ruinously expensive - 45 quid - and sold as a non-runner. Slightly complex battery replacement too as illustrated by the poor quality pictures taken at the time:
Back of watch showing Abu Dhabi airport shop sticker ( I think). Note the holes around the back of the watch - to let the sound out!
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The true case back is the flat, black metal disc that is a push fit into the case and is clamped down by the outer back, secured by the normal four screws
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Under the flat disc, now upside down and showing the silicone gasket is another disc, marked e40 and a rubber shock absorber. This is the first watch I have opened where the module wanted to come out with the rubber disc.
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Rubber shock absorber, module (2171) and old CR-2016
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Partly back together, awaiting e40 plate (sound plate or resonator?), black functional back and stainless decorative back. I assume the e40 plate is what makes it so loud, easy to hear the hour or alarm signal even with radio or TV playing. Note the two cil springs and the one tongue spring.
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Just realised that these photos show me "making the beast with two backs ..."