TM 1-1520-238-10 Change 8 4-63 4.31.6 TADS Manual Servo Drift Null. 1. SLAVE switch – Press and verify dotted cross- hair is present on selected display (HOD or HDD). 2. SIGHT SEL switch – TADS. 3. Verify TADS turret slews to fixed forward posi- tion by observing solid crosshair coming to cen- ter of display and cueing LOS centering on cue- ing dot. 4. SLAVE Switch – Press. 5. Sensor select switch – TV or FLIR. For greatest accuracy, use TV. 6. Field-of-view select switch – N. 7. Aim reticle at an easily observed object. 8. BRSIT ENABLE switch – UP, wait 5 seconds then adjust left and right thumbwheel controls for drift null. 9. BRSIT ENABLE switch – CENTER. 4.31.7 TADS Boresight. WARNING Ensure proper laser safety procedures are followed. NOTE Boresighting of the DTV and FLIR narrow and zoom fields-of-view occurs indepen- dently; the actual order is not critical. How- ever, DTV must be boresighted prior to boresighting the DVO. a.CUE Update Procedure. NOTE The CUE update procedure should be accomplished whenever the TADS FLIR is reported as being unable to be inter- nally boresighted. Once the CUE update procedure has been accomplished and the TADS FLIR still cannot be bore- sighted, continue with troubleshooting as specified in TM 9-1270-476-20. TADS internal boresight shall be per- formed after a cue update procedure. 1. SIGHT SEL switch – TADS. 2. Sensor select switch – TV. 3. Field-of-view select switch – W. 4. BRSIT switch – TADS. 5. SLAVE switch – Actuate. Verify internal bore- sight message replaced by cue update mes- sage. 6. If reticle does not appear centered on the black cross, execute the following: a. BRSIT ENABLE switch – UP. b. Use thumbforce controller to position DTV reticle in proximity to the black cross. c. BRSIT ENABLE switch – CENTER. d. SLAVE switch – Actuate. Verify cue update message replaced by internal boresight message. e. BRSIT TADS switch – OFF. Procedure com- plete, continue as desired. b. TADS Internal Boresight. NOTE TADS internal boresight shall be performed after performing a cue update, manual bore- sight adjust, or after replacement of the fol- lowing TADS components: TADS Electronic Unit (TEU), Night Sensor Assembly (NSA), Day Sensor Assembly (DSA), Laser Tran- ceiver Unit (LTU), Television Sensor Assem- bly (TV), or Boresight Assembly (BSA). 1.  DTV a. PLT/GND ORIDE switch – As required. b. CPG ARM/SAFE switch – ARM. c. SIGHT SEL switch – TADS. d. BRSIT switch – TADS. Confirm INTERNAL BORESIGHT message is present. e. LSR switch – ON. f. Sensor select switch – TV. g. Field-of-view select switch – N. h. Tracker polarity white over black. i. Laser trigger – Press and hold. j. BRSIT ENABLE switch – UP. Observe tracking gates capture laser spot. Continue to fire laser until tracking gates disappear. If spot cannot be captured by tracking gates, perform manual boresight adjustment, para- graph 4.31.7 d. k. BRSIT ENABLE switch – CENTER.