K2000 copper strip - what is it?

Hi! I am trying to resurrect my K2000 (actually a K2vx, but I think that doesn’t matter). Of course I stored it with batteries in, and am suffering for it.
I have the back off. There’s a very thin band of copper underneath that runs the length (more or less) of the keyboard. The side by the battery compartment is very corroded and I think suffered when I tried to clean it (I thought it was THICK copper…). Can any one tell me what the copper strips purpose is?
Pic attached
Thanks!

The copper is used to secure and ground the shielding so the main board is shielded for any transient noise to bleed out and be amplified. If I’m not mistaken.

ground and shielding.
Note the K2000 some iterations, the early ones, used to use audio-cable connections, the ground to ‘wick’ away heat - . so you could burn out your K2000 if you had it on for a good while with just the headphones attached. They changed this later.

Super, thank you!
I was able to refit a standard-issue battery back (old one filled with residue, spring broke off while cleaning) and it works well, Except for some patches, which I believe call on themselves and create a feedback loop. Later (prob. in a week) I will post those patches in the hope that someone can suggest what the issue might be and how to resolve it. A friend suggested that one of the chips in the effects section may have failed.

hi,
yes make a battery pack and now use rechargeables which don’t leak - the circuit itself doesn’t recharge but its best practice to use rechargebles here because its a low trickle and you won’t be changing these batteries for a very long time. Also today’s batteries are not as well made as the past, both in terms of chemistry and the seals. Ladda Ikea are actually Eneloop Panasonic Japan get those.

The ‘noise’ you hear in patches does it go if you bypass the effects? There is a common problem associated with the effects and ‘digital noise’ appearing in the chorus fx in particular. If you look at the K2000 circuit you’ll see the effects are bussed out, undergo ADC conversion to a Digitech chip and then bussed back out.

The sram chips from Hitachi are known to fail but often it can be a bad socket. So trying cleaning the socket and reinsert/insert the chip a couple of times for good contact and try again. Order the SRAM usually a narrow body 6116. Good brands are IDT for this particular chip.

Run ‘Diags’ and test the SRAM for the FX test.

By the way there is an active group on Facebook : Kurzweil K2 Series User Group

you can find files, more know-how and help.