Mod a 9V rechargeable battery to give you +3.6V, Ground and -3.6V.
You will appreciate this idea if you ever had to clobber together a bunch of AAs or AAAs to get a project working.
This instructable was meant to be part of a larger project, but I decided to submit this part alone to the 9V battery group.
You need to start with a 9V rechargeable battery (actually 8.4V but in a 9V package).
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