Poly 800/ not sure where to put this?

[dragonworks1]

Hello everyone. Sorry to come here with a problem right off the bat but I am between a rock and a hard place. I picked up a Poly 800 on the cheap, no sound. I was able to work up a voice from scratch and everything seems to be working correctly. Upon shutting her down, the voice I worked up was lost. So, okay, replace the internal battery backup. I open her up and I cannot find the battery. I go to a youtube video for battery replacement and find where the battery should be. Its not there. There is no battery symbol on the board like in the video. There is no evidence of a battery ever being desoldered? Okay, I download the service manual. No battery shown in the schematics or on the circuit board layout itself! No battery in the parts list so I am not even sure what battery it is supposed to take. I figured I would just check the schematic and see where to solder a battery holder in but that isn't happening. In the videos I watched I couldn't see which traces to solder the battery holder to. They were either too fast or not close up enough for me to see.
I owned one of these back in the eighties and it was fun to play with. I know everythng is working and I don't want to junk this keyboard because I cannot find where to put the battery.
I originally posted this in the new to the site forum but received no responses so I figured I would try here. Don't know if this is the right place to put it or not?
Can anyone help here?
Thanx
J.Dragon

[voip]

The Poly 800 (Mk I) relies on power from the batteries in the battery compartment to supply the current necessary to retain the contents of the static RAM. There is also sufficient stored charge in power supply capacitance to retain the memory contents for around a max of 4 minutes. Battery voltage must also be over 6 Volts to retain the static RAM contents. A bettery close to 6V will not give the user much time for a battery change!!

The Poly 800 Mk II uses a lithium battery for memory retention, which should be located on PCB assembly KLM-1032.

.

[dragonworks1]

Thank you very much. I was beginning to suspect that and asked that question at other places but never got an answer. I guess I am going to have to go out and buy some C batteries. Once again, thank you. I am almost sure that is the answer. When I get some batteries and put them in and test her I will come back and let you know. Now I have to find a way to restore the factory presets or just work up a bunch from scratch. Also, the battery cover on the back is missing, I would hazard a guess that they are no longer available and duct tape will have to come to the rescue.
Thank You
J. Dragon