According to a preferred aspect of the instant invention, there is provided herein a system and method for creating low frequency seismic waves. The controller applies, to each of the electrostatic mirrors, a reflection voltage allowing the electrostatic mirrors to reflect the charged particle beam at a predetermined timing so that the charged particle beam from the electron gun is reflected by the at least two electrostatic mirrors a plurality of times. The encrypted signal is transmitted to another electronic transmission apparatus if that apparatus does not have a recording capability and determined to be authorized using a second authentication process. A friction spring couples to the throttle member and includes a coil portion frictionally engaged with the linkage. The method relates to insertion of disc defect repair materials that are substantially two-dimensionally shaped and which allow for insertion and preferably self retention within the disc defect with plugging of the annulus fibrosis. Oscillator-based timing signals are acquired that are associated with the plurality of digitally controlled temperature-compensated crystal oscillators and a time correction is determined to apply to the seismic data acquired with the first autonomous seismic data acquisition unit.