A TDCS device. Trans-cranial Direct Current Stimulation, mostly experimental, somewhat proven for short-term depression and cognition improvement. Motivation was my solution would be simpler and easier to control as well as include triple safety.
I had little trust for the Chinese IC steered devices nor the early US attempters at pop market that refuse to describe even their safety approach.
Pleased with my personal results. Would not openly recommend doing it, because the DIY route as well as adopting TDCS do require that you can competently read medical studies. At least half of those I browsed fail good science test even at first glance.
And then of course the manufacturers and sellers are even worse, such as they are quite good at parroting misquotes of study results for marketing and PR.
Next plan is build an ECG and my own medical ultrasound, although with that one it is probably best to wait for about 5 to 7 years till the new-tech ultrasound generators get to market.
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