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vibra-tech <br />VIBRA-TECH ENGINEERS INC., "EVERLERT II" DIGITAL BLASTING SEISMOGRAPH. <br />SPECIFICATIONS: <br />The EVERLERT I1 digital blasting seismograph is a microprocessor based <br />instrument that records seismic and overpressure data on a 3+" 1.44 MB floppy disk. <br />The disk has a capacity of 75 to 100 typical blast events, and allows permanent <br />storage and retrieval of vibration data for further third-party computer analysis <br />as required. These analyses include peak particle velocity, frequency response <br />analysis (RSVP), VIBRA-MAPm and Fourier analysis. <br />The system may be operated by persons without specialised experience and who <br />have only a minimum of training. It has no complicated keyboard, and it can be set <br />up to record events in the field in less than a minute. To check out and arm the <br />instrument following simple field assembly, the operator simply presses the "ON" <br />button, then the "CALIBRATE" button, and finally the "MONITOR" button. <br />Seismic and overpressure trigger levels are changed by using the large LCD <br />screen located inside the lid of the instrument and a separate bank of four keys. <br />"UP" and "DONN" keys select the required trigger levels, and the "ENTER" key stores <br />the selection until a change is desired. <br />Unlike other instruments, the EVERLERT II does not need to be programmed by the <br />operator to collect data over a specific sampling period of seconds. It will <br />continue to record for whatever period the vibration (ground motion or air <br />overpressure) continues to persist and this not only simplifies set-up, but ensures <br />that all significant data are collected. <br />In addition to this feature, the EVERLERT II is autoranging, needing no prior <br />"sensitivity" setting, and it will automatically record all ground motion levels <br />from 0.01"/second to 8.0"/second, with air overpressures from 100 d8L up to 160 dBL. <br />The instrument can be set up to trigger separately on ground motion or air <br />overpressure alone, or on either effect. Immediately upon triggering, the event <br />data are written to the disk, and the analysed waveforms are displayed on the high <br />resolution graphics LCD screen. <br />By simple commands, the disk can also be employed to display any previously <br />recorded waveforms on the screen. The instrument's ability to display graphics as <br />well as text is unique to the EVERLERT II. This is an invaluable public relations <br />tool, as well as a most useful vibration analysis enhancement. <br />The system embodies powerful flexibility, in that the disk drive can also be <br />used to load other analysis programs onto the instrument, techniques such as RSYP, <br />VIBRA-MAP® and other analysis developments that future blast vibration technology <br />advances may permit. <br />An optional printer is provided for the EVERLERT 11. This printer module fits <br />into the front panel, and is easily removed for loading, maintenance, or use with <br />other EVERLERT II instruments. This printer is not essential for the operation of <br />the instrument, and therefore, while it can be used mounted in the instrument in <br />the field for immediate post-event printouts, it may also be left in the site <br />office for use following an event, with the recording instrument, or shared with <br />3-2 <br />Page 1 <br />