Abstract: An auto-extending antenna for a portable radio having a housing which can be closed is inserted into an aperture within the housing. As the housing of a radio using the auto-extending antenna is opened, a toothed wheel attached to the opening portion of the housing is rotated. This toothed wheel is coupled to a second toothed wheel and causes the second toothed wheel to rotate. The second toothed wheel is connected to a first hollow tube which has two opposing slots extending along almost the entire length of the tube. An antenna is inserted into the hollow portion of the first tube, and two opposing nobs attached to the bottom of the antenna protrude through the opposing slots. A second hollow tube fits over the first hollow tube. The inner walls of the second hollow tube have two opposing screw paths winding up its entire length. The nobs extend into the screw paths. The second tube is secured to the housing of the radio.