OPERATION MANUAL - Scintrex

Maintaining Your CG-5 and Trouble-shootingLevel the instrument (using the tripod setupprocedures) to within -10 to + 10 arcseconds aboutboth axes.PRESSPRESSMEASURECLRF5Press the key. The Autogravnow automatically takes and records a reading onceevery 60 seconds (57 sec for each reading and threeseconds for calculation overhead).After 12 - 24 hours, press the F5 key.Output the data to a computer. For details on thisprocedure, please see Chapter 3, “Operating theCG-5 in the Field” and the “Dumping Data” topicthat starts on page 3-20.Below is a procedure for calculating the Driftconstant. The data could also be processed in aspreadsheet or other processing package.Reading the DataFrom the listing, take one reading (R1) at time T1close to the start of the recording period and anotherreading (R2) at time T2 from near the end of theperiod.Important:Do not use readings which are obviously noisy ordisturbed.From these values, calculate a new Drift Correction.DRIFT' =DRIFT +R2 – R1--------------------T2 – T15-14CG-5 Manual - part # 867700 Revision 2