When a radio-button is not yet chosen

I have three radio-buttons for "kind of project":

• personal / unregistered nonprofit / registered nonprofit

I also have text input "Organization name" below the radio buttons.

"Organization name" input should be disabled if the user chooses "personal" project.

I think I should initially leave all three radio-buttons unchecked and require the user to check one of them, when he submits the form.

Should "organization name" be disabled initially, when no radio-button are chosen?