New results on the experimental investigation of the electron in a diamond crystal, obtained at the Tomsk synchrotron, are presented. The experimental data are systematized in such a way that it allows observation of a transition from axial to planar channeling and the variation of a maximum position in the radiation spectrum at planar channeling with the electron energy change. A comparison of the spectra of the coherent bremsstrahlung radiation and radiation at planar and axial channeling is performed, and the radiation losses in angular cone 1/γ are obtained.