DX7s (DX7 mk2) Fix "Change Battery" Error HOWTO

How to unsolder the original battery in a DX7s and solder a new wire and battery holder for a CR2032 battery. All steps clearly explained including relevant testing, and how to load sounds again once the battery is working again. Switch captions on for simplified subtitles naming the task at each step.
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Please watch: "Time after Time - Cyndi Lauper (Guitar Vocal cover)"
• Time after Time - Cynd...
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