The Poly-61's envelopes have now been repaired but a test of the back-up battery, seen here, showed it to be extremely low in voltage.

The battery was therefore unsoldered and removed from the CPU board.

Here you see the old battery alongside a new replacement.

The new battery is smaller in size due to its lower capacity (80 mAh) but is a suitable, 3.6V rechargeable supply.  The capacity isn't so important in this trickle-charge, very low current application.

The new battery has a nickel metal-hydride chemistry instead of the toxic and now restricted nickel cadmium chemistry used by the original.

However, a higher capacity (150 mAh) NiMH battery for the Korg Poly-61 and Korg Polysix is now available on our Battery Page.

Here you see the new battery installed on the CPU board.

Here, the CPU board has been reinstalled into the Korg Poly-61M.

Notice that new cable ties have been installed to replace those previously cut, keeping the cables neatly dressed and secure.