Turns out this was not the manual i was looking for. The concertmate 670 keyboard i have is a "Realistic" model made for Radio Shack and none of the diagrams on the owners manual i received matches up. HOWEVER, I must say the service Owners Manual provides was fast and efficient by being available online. The manual was in good readable condition and easily downloaded.
Thank´s for your help, I already recived these manual from you
Text excerpt from page 406 (click to view)
Addendum to explain how to exit PICTURE MENU LOCK MODE
If you try to adjust PICTURE MENU and the following message is displayed on-screen, please follow the procedure below to exit this mode.
PICTURE MENU LOCK MODE REFER TO OWNER�S MANUAL TO EXIT THIS MODE
Procedure � Press ACTION and CH mode.
buttons on the TV front panel simultaneously to exit this