First of all, here is a direct link to the ONLINE USER'S MANUAL for that model:
To view the Owner's Manual with Operating Instructions just use your mouse to click on the link, which is the underlined and highlighted text just above. This will open a new web browser page automatically for you and allow you to view the information at the website indicated and the contents of the Owner's Manual.
You may need ADOBE READER installed on your computer to read PDF documents.
You can download this free at WWW.ADOBE.COM
Click on the DOWNLOAD ADOBE READER button on right side of the ADOBE home page when you get there, then follow the onscreen instructions to install the software on your computer.
See page 4 of the manual for instructions on using batteries with the unit.
It says there that it requires 8 D-cell batteries, not the C-cells that you quoted..
Also try removing the wall adapter power supply plug to the unit when you are using batteries.
I hope that was helpful to you, good luck.
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