Ron, Are you talking about the kit with three knobs on the left side or the 300 in one kit with the two knobs on the left ?? Might be able to help you if it is the 300 in one. Best regards, Steven Subject: Radio Shack Science Fair manuals Do you know where i can get a manual for the Science Fair electronic project kit # 28-247? I would like to give it to my son for Christmas so a manual would be great. Thanks Ron