75010602 2024 192 11:00 2 9 PMT cube receive cable 75010602 2024 151 18:21 1 9 XL-DC replacement with a spare one 75010602 2023 192 13:26 1 6 ARSU (amplifier Receive Select Unit ) was replaced with the upgraded unit. 75010602 2023 191 10:20 1 6 PMT power connector and power cable inside PMT was replaced. 75010602 2023 057 11:27 2 0 Calibration RMS was higher than normal due to Laser brag angle misaligned, the issue was fixed on 02/26/2023 75010602 2022 324 11:48 1 6 PD 10 batteries replaced and replacement of ND filters and measure 1.72V @ 2mm RMS 75010602 2022 232 11:27 1 6 Replaced of default PMT cable. 75010602 2022 232 11:27 1 6 The default PMT cable was causing larger than nominal RMSs and several mm to cm level instabilities in our system delay. 75010602 2022 228 14:55 2 6 Replaced Event Timer Module S/n 1309-B-006 by Event Timer Module S/n 1309-B-009 75010602 2022 220 11:30 0 6 Replaced Amplifier capacitor bank CB632H 75010602 2022 206 10:25 0 6 Replace Event Time Module power supply and 1 PPS cable from XLDC to LRC 75010602 2022 070 09:20 0 99 Processor computer was replaced 75010602 2022 060 10:00 0 99 Display chassis #2 upgraded 75010602 2021 201 09:01 0 6 Chiller replacement ( with the new chiller in stock) 75010602 2021 134 14:30 0 9 Replaces XL-DC antenna and cable 75010602 2021 117 10:20 1 9 Problem that we have experience with the XL-DC that we receive few weeks ago was: 1. Could not find any satellite, 2. It triggers TCG card fly wheeling. Solution: XL-DC Receive card was swap with the old XL-DC receive card. 75010602 2021 095 10:00 1 9 Replaces XL-DC with the Old XL -DC and swap PD 10 from the new unit to the old unit 75010602 2021 091 11:00 1 9 Replace XL-DC 75010602 2021 089 17:00 0 6 Replace two (2) MPCs Encoders 75010602 2020 332 20:30 0 5 Replace low loss transmit cable 75010602 2020 328 09:00 1 5 CNS clock replaced 75010602 2020 300 00:00 1 5 Chiller was repaired and installed back into the system 75010602 2020 275 00:00 1 5 Amplifier flash lamp replaced 75010602 2020 275 00:00 1 5 PU 430 s/n #H 130 NASA tag no.577429 replaced with PU 430 s/n C 057 # NASA tag G77282 75010602 2020 273 00:00 2 6 PMT supply voltage is now kept the same between calibration and the subsequent measurement session. PMT voltage used is typically 2700 V for day-time tracking, and 3000 V for night-time tracking 75010602 2020 035 00:00 0 05 CU401 running on original power supply 75010602 2020 029 00:00 0 05 CU401 running on a bench power supply 75010602 2020 028 00:00 0 05 CU401 down 75010602 2020 019 00:00 1 99 Changed firing rate of all Glonass, Etalon 1 and Etalon 2 to 5PPS 75010602 2020 016 00:00 0 06 PD10 photodetector power supply batteries replaced 75010602 2019 277 00:00 1 06 PMT high voltage power supply replaced 75010602 2019 277 00:00 1 06:02:01 Receive cable replaced with the insulated one 75010602 2019 269 08:30 1 9 Relocated the two GPS antennas on the van roof 4.05 meters from original position towards the Radar. 75010602 2019 265 00:00 0 09 Additional 1PPS output programmed on XL-DC 75010602 2019 199 00:00 1 12:01:02 MET4 unit relocated to the pole 75010602 2019 150 00:00 0 06 Iris replaced 75010602 2019 079 00:00 0 99 New aircon installed in the laser room 75010602 2019 045 00:00 1 06:02:03 Replaced TIU 5370B 75010602 2019 039 00:00 0 99 Replaced hot air bypass valve on the chiller 75010602 2019 036 00:00 0 06 PD10 photodetector power supply batteries replaced 75010602 2019 007 00:00 1 05 45 degree turning mirror (15d) replaced on the laser table 75010602 2018 340 00:00 0 99 Aircon issues 75010602 2018 333 00:00 1 05 Laser alignment performed 75010602 2018 312 00:00 0 06 OAM down 75010602 2018 276 00:00 1 06:02:03 TIU 5370B faulty 75010602 2018 263 00:00 0 99 Aircon issues 75010602 2018 242 00:30 1 05 Logic card from old PU430 installed on new PU430 75010602 2018 242 00:00 1 05 PU430 replaced 75010602 2018 218 00:00 1 05 PU420 down 75010602 2018 207 00:00 1 05 Capacitor banks down 75010602 2018 204 00:00 0 99 Controller computer replaced with the spare 75010602 2018 194 00:00 1 05 Capacitor banks down 75010602 2018 180 00:30 0 99 Controller is using 100% disk space 75010602 2018 180 00:15 0 99 Processor computer froze during back up 75010602 2018 180 00:00 0 99 Controller and processor computers backed up 75010602 2018 166 00:00 1 06:02:03 TIU 5370B faulty 75010602 2018 165 00:00 0 04 MPACs 5V power supply replaced 75010602 2018 164 00:00 0 04 MPACs shut down 75010602 2018 116 00:00 0 04 MPACs cable W713 modified by cutting 5V supply to the mount remote station 75010602 2018 098 00:00 1 06 PMT high voltage power supply replaced 75010602 2018 017 00:00 0 05 Replaced microswitch on the laser amplifier head 75010602 2018 011 00:00 0 06 Replaced OAM 75010602 2017 307 00:00 1 09 XL-DC receiver replaced 75010602 2017 232 00:00 0 99 Chiller pump replaced 75010602 2017 146 00:00 1 06 Repaired PMT gating cable 75010602 2017 142 00:00 1 06 PMT power supply cable connector replaced 75010602 2017 142 00:00 1 06:02:01 Reinstall the old discriminator (SN263) back in the system 75010602 2017 137 00:00 1 06:02:01 Discriminator (SN263) replaced with SN306 75010602 2016 270 00:00 0 11:01 Radar installation 75010602 2016 174 00:00 1 09 XL-DC replaced 75010602 2016 074 00:00 0 06 PD10 photodetector power supply batteries replaced 75010602 2015 153 00:00 0 4:01 Replacement of dual Amplifier 75010602 2015 152 00:00 0 4:01 System dual Amplifier faulty 75010602 2015 109 00:00 0 11:01 Station down due to radar temperature sensor 75010602 2015 013 00:00 0 11:01 Replacement of the Radar 75010602 2015 012 00:00 0 11:01 Radar was removed for repair 75010602 2015 012 00:00 0 99 Replacement of system controller computer 75010602 2015 007 00:00 0 99 System Controller computer failed 75010602 2015 007 00:00 0 99 System controller computer faulty 75010602 2014 287 00:00 2 06:02:01 Replacement of receive cable 75010602 2014 276 00:00 0 11:01 Station operational, radar verification was done 75010602 2014 274 00:00 0 11:01 Replacement of radar control card, remote card and radar transceiver box 75010602 2014 251 00:00 0 11:01 Station down, Radar failed 75010602 2014 230 00:00 2 06:02:01 Replacement of HSLR discriminator 75010602 2013 231 00:00 0 11:01 Radar verification test done 75010602 2013 227 00:00 0 11:01 Replacement of the Radar 75010602 2013 212 00:00 0 04:01 System Dual Amplifier replaced 75010602 2013 185 00:00 0 99 Replacement of east door worm drive 75010602 2013 163 00:00 0 04:01 System Dual Amplifier failed 75010602 2013 108 00:00 0 12:01:02 Replacement of Paroscientific (MET 4) 75010602 2013 061 00:00 0 05 replaced frequency synthesizer (AML) 75010602 2013 052 00:00 0 99 Replacement of the following units: Laser power unit (PU430), Trigger Level, Capacitor bank 75010602 2012 299 00:00 0 99 Replacement of True Time GPS (Time & frequency Receiver 75010602 2012 171 00:00 0 99 Replacement of high voltage power supply 75010602 2012 076 00:00 0 99 Station was operational 75010602 2012 016 00:00 0 99 Station down due to laser failure and alignment photo detector was faulty. 75010602 2011 347 00:00 0 99 Replacement of air conditioner 75010602 2011 313 00:00 0 99 Replacement of standby power supply battery batteries 75010602 2011 249 00:00 2 06:01:01 Replacement of receive cable 75010602 2011 082 00:00 0 10 replaced laser table and HP5370B TIU 75010602 2011 010 00:00 0 10 replaced Symmetricom XL/DC GPS Rb receiver 75010602 2010 224 00:00 0 06 replaced Delay Box, Constant Fraction Discriminator 75010602 2010 223 00:00 0 99 Replacement of a new Nim-Bin power supply 75010602 2010 217 00:00 0 11:01 Radar optical/RF alignment done 75010602 2010 216 00:00 0 11:01 Orthoganlity of axes checked using a laser, Radar put on roof 75010602 2010 216 00:00 0 11:01 Radar leveled 75010602 2010 216 00:00 0 11:01 Replacement electronics Delay Box 75010602 2010 214 00:00 0 11:01 Replacement of the azimuth harmonic drive of the radar 75010602 2010 214 00:00 0 11:01 Replacement resolvers, radar elevation support, CFD, and drive belts 75010602 2010 197 00:00 0 99 Installed new sattrk version 7.1, 16 July, 2010 75010602 2010 196 00:00 0 12:01:01 Replacement of New Paroscientific (MET 3) 75010602 2010 145 00:00 0 10 replaced HP5370B TIU 75010602 2010 069 00:00 0 99 Installed sattrk version 502 75010602 2009 330 00:00 0 05 new LRO-LR capability 75010602 2009 273 00:00 0 05 replaced laser oscillator head 75010602 2009 247 00:00 0 05 new h/w and s/w for 10 Hz operations 75010602 2009 160 00:00 3 99 installed new processor computer 75010602 2009 131 00:00 0 06 replaced Constant Fraction Discriminator 75010602 2008 310 00:00 0 05 saturable laser upgrade 75010602 2008 094 00:00 3 99 installed new controller computer