Transponder beam

The Transponder beam was the secret weapon of Mastermind.

The New Scooby-Doo Mysteries
Mastermind acted as a tour guide, giving tours of the Statue of Liberty as cover for building a satellite transponder that would enable him to take over the world.

Appearances

 * The New Scooby-Doo Mysteries
 * 104(a). Mission: Un-Doo-Able