Changes for page ANU Seismic Data Loggers

Last modified by robert on 2025/08/08 16:09

From version 54.1
edited by santi
on 2025/07/22 18:14
Change comment: There is no comment for this version
To version 41.1
edited by robert
on 2025/03/03 18:19
Change comment: There is no comment for this version

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1 +XWiki.robert
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2 2  (((
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4 -(((
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8 -(((
9 9  ANU has designed and built three generations of seismic data recorders, two of which (the small yellow TerraSAWR and the larger beige LPR-200) are still in use today. Despite their contrasting appearance, they both use the same software, data cards, and have the same instrument response.
10 10  )))
11 -)))
12 12  
13 -= Power Considerations =
14 -
15 -Both the LPR-200 (or "Low Power Recorder" 200) and TerraSAWR are designed to use as little power as possible, and more or less use the same amount of power.
16 -
17 -At 100 Hz and with a GPS cable connected these loggers draw about 220 mW of power once the screen is off (higher sample rates draw more power but only marginally, < 5 mW). Adding a sensor (e.g. a Trillium Compact 120) increases this to approximately 400 mW, or 0.4 volt-amps. So, in theory 7 Ah battery should last about 10 days without a solar panel, but in practice it seems to be a bit closer to 8 which may be due to variability in power drain while in getting GPS locks.
18 -
19 -For very sunny environments (latitudes < 30) a 20 Volts 10 Watt solar panel should have no issue keeping these loggers alive over the summer months, and assuming unobstructed skies should also be fine over winter. However there is no harm in using 20 or even a 40 Watt panel, especially for high latitudes, coastal regions, or areas without a full sky view. In theory up to a 60 Watt solar panel is fine, but we don't recommend anything over 40 Watts and that amount of power is already overkill.
20 -
21 -(% class="box infomessage" %)
22 -(((
23 -Power issues are easy and cheap to solve relative to the cost of your experiment, don't skimp!
24 -)))
25 -
26 -(% class="wikigeneratedid" %)
27 -In the case of an LPR, there is a large compartment for housing an internal battery, able to accommodate anything from a 10-30Ah battery. To use a standard lead acid battery with a positive and negative terminal, a 6 pin adaptor must be used. This ensures the voltage from the external power port (pins A and C) connect to the battery and ensure the system actually recharges. (See [[Peripheral Equipment>>doc:Instrumentation.Peripheral Equipment.WebHome]] for a more comprehensive overview of this kind of setup)
28 -
29 29  = Data Card Formatting and Information =
30 30  
31 -Both the TerraSAWR and LPR-200 require SD Cards to be formatted in FAT32 filesystem. For 64Gb cards it can be difficult to format in FAT32, but [[software >>http://auspass.edu.au/field/fat32cardformatter.exe]]is available. ANU recommend SanDisk Extreme 150 mb/s cards in either 32 or 64Gb size. We strongly discourage using cards larger than 64Gb, and in general smaller cards are less likely to fail. We have also found that "adapter" cards (e.g. SD to microSD) are prone to having write issues and **strongly** advise against them.
8 +Both the TerraSAWR and LPR-200 require SD Cards to be formatted in FAT32 filesystem. For 64Gb cards it can be difficult to format in FAT32, but [[software >>url:http://auspass.edu.au/field/fat32cardformatter.exe]]is available. ANU recommend SanDisk Extreme 150 mb/s cards in either 32 or 64Gb size. We strongly discourage using cards larger than 64Gb, and in general smaller cards are less likely to fail. We have also found that "adapter" cards (e.g. SD to microSD) are prone to having write issues and **strongly** advise against them.
32 32  
33 -The loggers can be "pre-programmed" with information (e.g. site name, sampling rate, etc) or they can be programmed in the field using the buttons on the logger. To pre-program the cards you simply edit a text file (named "[[ANUSRSetup.txt>>http://auspass.edu.au/field/ANUSRSetup.txt]]" for the LPRs, or "[[tSAWRSetup.txt>>http://auspass.edu.au/field/tSAWRSetup.txt]]" for the TerraSAWRs) and place it in the root directory on the SDCard. When the logger boots up, it will parse and load this information.
10 +The loggers can be "pre-programmed" with information (e.g. site name, sampling rate, etc) or they can be programmed in the field using the buttons on the logger. To pre-program the cards you simply edit a text file (named "[[ANUSRSetup.txt>>url:http://auspass.edu.au/field/ANUSRSetup.txt]]" for the LPRs, or "[[tSAWRSetup.txt>>url:http://auspass.edu.au/field/tSAWRSetup.txt]]" for the TerraSAWRs) and place it in the root directory on the SDCard. When the logger boots up, it will parse and load this information.
34 34  
35 -== The format for ANUSRSetup.txt / LPR200s will be a single line of text that looks like this: ==
12 +=== The format for ANUSRSetup.txt / LPR200s will be a single line of text that looks like this: ===
36 36  
37 37  {{{XXX195G0100010034864 2 }}}
38 38  
39 -//corresponding to//
16 +corresponding to site XXX19,
17 + network 5G,
18 + sample rate 0100, (i.e. 100 Hz)
19 + "gps interval" 01 (once per hour~-~- don't change),
20 + start mode (always 0),
21 + stop mode (always 0),
22 + seismometer type (3 = broadband (+/- 20V), 2 = Guralp (+/- 10V), 1 = shortperiod (+/- 5V),
23 + and seismometer serial number (4864).
40 40  
41 - site **XXX19**,
42 - network **5G**,
43 - sample rate **0100**, (i.e. 100 Hz)
44 - "gps interval" **01** (once per hour~-~- don't change),
45 - start mode (always **0**),
46 - stop mode (always **0**),
47 - seismometer type (**3** = broadband (+/- 20V), 2 = Guralp (+/- 10V), 1 = shortperiod (+/- 5V),
48 - and seismometer serial number (**4864**).
49 -
50 50  (% class="box warningmessage" %)
51 51  (((
52 52  NOTE: the 2 at the very end is for "RECORD ON RESTART". The record on restart option ensures that if the logger dies and is powered back up whilst in the field (due to battery charging cycles or other causes) that the recording will resume. (# of blank spaces before this doesn't matter)
53 53  )))
54 54  
55 -== The format for TSAWR loggers is shorter: ==
30 +=== The format for TSAWR loggers is shorter: ===
56 56  
57 57  (% class="box errormessage" %)
58 58  (((
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71 71   and seismometer serial number (9999).
72 72  
73 73  
74 -== The formatting process using the logger: ==
49 +=== The formatting process using the logger: ===
75 75  
76 76  The process for formatting an SD card within the logger is straightforward. Navigate to the "SD INFORMATION" screen and press ERASE SD CARD. This process may take up to a minute. This will result in erasing all files from the card. Upon starting recording, a new 'seed' will be written containing all the information that the logger has been set with FINISH THIS SECTION
77 77  
78 -[[image:original_0747763c-e3dd-4667-b897-833f12c8e0b8_20241219_130604.jpg||height="240" width="298"]]
53 +[[image:/xwiki/bin/download/Instrumentation/ANU%20LPR-200/WebHome/original_0747763c-e3dd-4667-b897-833f12c8e0b8_20241219_130604.jpg?width=298&height=240&rev=1.1||alt="original_0747763c-e3dd-4667-b897-833f12c8e0b8_20241219_130604.jpg" height="240" width="298"]]
79 79  
80 80  Here is a general guideline for how much data you can expect to fit on a card:
81 81  
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83 83   32Gb card: 122 days @ 250hz or 305 days @ 100hz
84 84  }}}
85 85  
86 -== Default Settings ==
87 87  
88 -As of 2025, the default settings for both LPR (v. 2.7) and TSWAR (v 3.6a) loggers are below. If you're using a broadband instrument, you are essentially good to go without having to program the cards.
89 -
90 -* XX.ANUSR network and station name
91 -* 100 Hz Sample Rate
92 -* 40 Vpp (or +/- 20 V) gain / Trillium Compact seismometer version
93 -* Record on Restart enabled
94 -
95 -Note that if a user sets the gain incorrectly, this can be fixed later (assuming nothing clipped) by multiplying or dividing by factors of 2. The gain setting can be looked up from the logfile, else you may have to guess from a PSD or other method.
96 -
97 97  = Logger Menus Overview (and setup) =
98 98  
99 99  The same menus are used in both the TSAWR and LPR-200 loggers.
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104 104  
105 105  This menu also displays the firmware version, battery, external, and solar voltages, and the temperature of the system.
106 106  
107 -* Check all Initialisation Parameters are marked as successful.
108 -* Check that solar voltage is above 10 V, otherwise the station will not last long.
72 +==== Upon setup ====
109 109  
74 +- Check all Initialisation Parameters are marked as successful.
75 +
76 +- Check that solar voltage is above 10 V, otherwise the station will not last long.
77 +
78 +
110 110  == Live Seismometer Data ==
111 111  
112 112  This screen displays real time seismometer data for all 3 axes of the seismometer. Initially, a plot of raw data from all 3 channels is shown. By pressing enter, a high pass filter can be applied showing a more useful plot of all channels. The up and down arrows can be used to change between a view of all channels, individual channels, and all channels on different X axes.
113 113  
114 -* Check that all 3 channels are present and are producing a signal.
115 -* Stomp on the ground near where the sensor is installed to check that a signal is being picked up by all 3 channels.
116 -* Common representations of poor signals include channels sloping smoothly from high values to zero, or sharp corners in the plots.
83 +==== Upon setup ====
117 117  
85 +- Check that all 3 channels are present and are producing a signal.
86 +
87 +- Stomp on the ground near where the sensor is installed to check that a signal is being picked up by all 3 channels.
88 +
89 +- Common representations of poor signals include channels sloping smoothly from high values to zero, or sharp corners in the plots.
90 +
91 +
118 118  == GPS Data ==
119 119  
120 120  This menu displays the status of the stations' GPS connection. The screen lists; UTC time, UTC date, latitude, longitude, altitude, number of satellite connections, and SNR.
121 121  
122 -* Check that the station is connected to satellites
96 +==== Upon setup ====
123 123  
98 +- Check that the station is connected to satellites
99 +
100 +
124 124  == SD Information ==
125 125  
126 126  The menu lists if the SD card has been initialised, as well as the capacity and space free on the memory card. See "Data card formatting" (above) to see how to format and initialise the inserted SD card.
127 127  
105 +
128 128  == System Configuration ==
129 129  
130 130  This menu is used to set the stations identifiers and parameters.
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137 137  
138 138  The seismometer model and serial number (up to 10 characters) can be set. Seismometer model options include:
139 139  
140 -* Trillium Compact (same for 20s and 120s models)
141 -* CMG - 3ESP
142 -* Guralp 40T
143 -* LE-3D Lite
144 -* Mark L4C
145 -* Mark L4
118 +- Trillium Compact
146 146  
120 +- CMG - 3ESP
121 +
122 +- Guralp 40T
123 +
124 +- LE-3D Lite
125 +
126 +- Mark L4C
127 +
128 +- Mark L4
129 +
147 147  Additionally, the following settings can be used in place of the seismometer model types: +/- 20V, +/- 10V, +/- 5V
148 148  
149 149  The record on restart option ensures that if the logger dies and is powered back up whilst in the field (due to battery charging cycles or other causes) that the recording will resume.
150 150  
151 -* Set the sampling rate, station identifier, and network code. Set the appropriate seismometer type. Most importantly, ensure the record on restart setting is checked.
134 +==== Upon setup ====
152 152  
136 +- Set the sampling rate, station identifier, and network code. Set the appropriate seismometer type. Most importantly, ensure the record on restart setting is checked.
137 +
153 153  (% class="box errormessage" %)
154 154  (((
155 155  NOTE: Ensure the 'RECORD ON RESTART' option is marked with a cross.
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156 156  )))
157 157  
158 158  (% class="wikigeneratedid" %)
159 -[[image:original_2b83fcf5-ee5a-4375-bab1-2d738e4ffe8c_20241219_130646.jpg||height="234" width="289"]]
144 +[[image:/xwiki/bin/download/Instrumentation/ANU%20LPR-200/WebHome/original_2b83fcf5-ee5a-4375-bab1-2d738e4ffe8c_20241219_130646.jpg?width=289&height=234&rev=1.1||alt="original_2b83fcf5-ee5a-4375-bab1-2d738e4ffe8c_20241219_130646.jpg" height="234" width="289"]]
160 160  
161 161  == STA/LTA Configuration ==
162 162  
163 -The Short Term Average and Long Term Average Configuration screen.. this is a relic for when people weren't recording continuously. Not advised!
148 +The Short Term Average and Long Term Average Configuration screen is no longer used.
164 164  
150 +
165 165  = LogFile Conversion Script =
166 166  
167 -Both the TSAWR and LPR-200 write logging information as a binary "dat" file which includes GPS time syncs, temperatures, battery power, and position. To convert them into ASCII you can read, use [[THIS PYTHON SCRIPT>>http://auspass.edu.au/field/anusr_log.py]].
153 +Both the TSAWR and LPR-200 write logging information as a binary "dat" file which includes GPS time syncs, temperatures, battery power, and position. To convert them into ASCII you can read, use [[THIS PYTHON SCRIPT>>url:http://auspass.edu.au/field/anusr_log.py]].
168 168  
155 +
169 169  = Instrument Response =
170 170  
171 -Both the TerraSAWR and LPR-200 use the same ADS1281 analog-to-digital converter chip and are designed to have identical instrument response. The ADC (analog to digital) chip in both loggers originally samples at 1024000 Hz and downsamples towards the output data rate via a 5th order SINC filter, then another four FIR filters. If the output is below 250 Hz, a final "pure" /5 decimation is done without any sort of FIR filter.
158 +Both the TerraSAWR and LPR-200 use the same ADS1281 analog-to-digital converter chip and are designed to have identical instrument response. Depending on the output sample rate (e.g. 100 Hz, 250 Hz, 500 Hz, 1000 Hz) amplitude response is consistently flat up to ~~100 Hz but phase response can vary above 1 Hz at 100 Hz (or 10 Hz at 250 Hz).
172 172  
173 -{{info}}
174 -The Stage 3 SINC coefficients (600+) during the initial 1024k > 16k decimation were left off as they slowed down the process x10 and contribute very little (< 0.3 db, < 0.31 ms) to the end result
175 -{{/info}}
160 +The user can choose to apply a 2nd stage "sensor gain" by selecting an instrument type in the setup menu. This effectively selects a 10 Vpp (e.g. short period sensors), 20 Vpp, 40 Vpp (most broadband sensors) regime to match the sensor's sensitivity. This has the effect of doubling amplitude from 10v to 20v, or quadrupling from 10v to 40v. If you have set your sensor correctly (and the signal isn't clipped!) you can "correct" this by simply multiplying your data by 0.5 etc.
176 176  
177 -The user can choose to apply a 2nd stage "sensor gain" by selecting an instrument type in the setup menu. This effectively selects a 10 Vpp (e.g. short period sensors), 20 Vpp, 40 Vpp (most broadband sensors) regime to match the sensor's sensitivity. This has the effect of doubling amplitude from 10v to 20v, or quadrupling from 10v to 40v. If you have set your sensor correctly (and the signal isn't clipped!) you can "correct" this by simply multiplying your data by 0.5 etc. This gain manifests itself in stage 2 in the response information.
162 +Another important thing to note is that the group delay associated with late stage FIR filters is **automatically applied in the logger**, hence there is no need to apply this in the response. These tend to max out at 0.124 seconds for most output sampling rates (0.062 s for 100 Hz).
178 178  
179 -Instrument response can be downloaded from IRIS [[Nominal Response Library>>https://ds.iris.edu/ds/nrl/]] if need be, or [[directly from us>>http://auspass.edu.au/data/logger_response]] , or by downloading the response of an equivalent sensor at AusPass (e.g. get_stations(level='response') ).
164 +Instrument response can be downloaded from IRIS-NRL (v2) if need be, or by downloading the response of an equivalent sensor at AusPass (e.g. get_stations(level='response') )
180 180  
181 -[[Huddle test comparing a Trillium Compact 120 + TerraSAWR vs a Trillium Compact 120 + Nanometrics Centaur (M8.AUANU)>>image:TC120_ANU_vs_CENTAUR.png||data-xwiki-image-style-alignment="center"]]
182 182  
183 -= ANU TerraSAWR (Gen 3, FW 3.5a, 2017- current) =
167 += ANU TerraSAWR (Gen 3, FW 3.5a, 2017?- current) =
184 184  
185 -Not sure there's much left to say
169 +Text here
186 186  
171 +== Sub-paragraph ==
187 187  
173 +XXXX
188 188  
175 +== Sub-paragraph ==
176 +
177 +xx
178 +
179 +
180 +
181 +
189 189  = ANU LPR-200 (Gen 2, FW 2.6a/2.7a, 2013 - current) =
190 190  
191 -Ditto the mighty LPR!
184 +Text here
192 192  
186 +== Sub-paragraph ==
193 193  
194 -= ANU "ANUSR" (Gen 1, 2003? - 2012) =
188 +x
195 195  
196 -This logger has been retired for a long time and has a different instrument response. It used modular component boards and was powered via an acrylic case of 6 x 6V lantern batteries. There is a somewhat complete one above the CAT lab door if anyone is so inclined to have a look.
197 197  
198 198  
192 += ANU "ANUSR" (Gen 1, 2003? - 2013?) =
193 +
194 +x
195 +
199 199  = References =
200 200  
201 -* [[PDF Manual>>http://auspass.edu.au/field/LPR-200_Instruction_Manual.pdf]]
202 -)))
198 +* [[PDF Manual>>url:http://auspass.edu.au/field/LPR-200_Instruction_Manual.pdf]]
199 +~)~)~)
203 203  
204 204  (% class="col-xs-12 col-sm-4" %)
205 205  (((
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207 207  (((
208 208  **Contents**
209 209  
210 -{{toc/}}
207 +(% class="wikitoc" %)
208 +* [[Data Card Formatting and Information>>path:#HDataCardFormattingandInformation]]
209 +**
210 +*** [[The format for ANUSRSetup.txt / LPR200s will be a single line of text that looks like this:>>path:#HTheformatforANUSRSetup.txt2FLPR200swillbeasinglelineoftextthatlookslikethis:]]
211 +*** [[The format for TSAWR loggers is shorter:>>path:#HTheformatforTSAWRloggersisshorter:]]
212 +*** [[The formatting process using the logger:>>path:#HTheformattingprocessusingthelogger:]]
213 +* [[Logger Menus Overview (and setup)>>path:#HLoggerMenusOverview28andsetup29]]
214 +** [[System Information>>path:#HSystemInformation]]
215 +***
216 +**** [[Upon setup>>path:#HUponsetup]]
217 +** [[Live Seismometer Data>>path:#HLiveSeismometerData]]
218 +***
219 +**** [[Upon setup>>path:#HUponsetup-1]]
220 +** [[GPS Data>>path:#HGPSData]]
221 +***
222 +**** [[Upon setup>>path:#HUponsetup-2]]
223 +** [[SD Information>>path:#HSDInformation]]
224 +** [[System Configuration>>path:#HSystemConfiguration]]
225 +***
226 +**** [[Upon setup>>path:#HUponsetup-3]]
227 +** [[STA/LTA Configuration>>path:#HSTA2FLTAConfiguration]]
228 +* [[LogFile Conversion Script>>path:#HLogFileConversionScript]]
229 +* [[Instrument Response>>path:#HInstrumentResponse]]
230 +* [[ANU TerraSAWR (Gen 3, FW 3.5a, 2017?- current)>>path:#HANUTerraSAWR28Gen32CFW3.5a2C20173F-current29]]
231 +** [[Sub-paragraph>>path:#HSub-paragraph]]
232 +** [[Sub-paragraph>>path:#HSub-paragraph-1]]
233 +* [[ANU LPR-200 (Gen 2, FW 2.6a/2.7a, 2013 - current)>>path:#HANULPR-20028Gen22CFW2.6a2F2.7a2C2013-current29]]
234 +** [[Sub-paragraph>>path:#HSub-paragraph-2]]
235 +* [[ANU "ANUSR" (Gen 1, 2003? - 2013?)>>path:#HANU22ANUSR2228Gen12C20033F-20133F29]]
236 +* [[References>>path:#HReferences]]
237 +* [[TerraSAWR Specs>>path:#HTerraSAWRSpecs]]
238 +* [[LPR-200 Specs>>path:#HLPR-200Specs]]
211 211  )))
212 212  
213 213  
214 -
215 -
216 -
217 -
218 -
219 -
220 -
221 -
222 -
223 -
224 224  (% class="box" %)
225 225  (((
226 226  = TerraSAWR Specs =
227 227  
228 228  
229 -[[image:Terrasawr 1.jpg]]
247 +[[image:/xwiki/bin/download/Instrumentation/ANU%20LPR-200/WebHome/Terrasawr%201.jpg?rev=1.1||alt="Terrasawr 1.jpg"]]
230 230  
231 -[[image:1704865206800-824.jpg]]
249 +[[image:/xwiki/bin/download/Instrumentation/ANU%20LPR-200/WebHome/1704865206800-824.jpg?rev=1.1||alt="1704865206800-824.jpg"]]
232 232  
233 -[[image:1704864886951-793.jpg]]
251 +[[image:/xwiki/bin/download/Instrumentation/ANU%20LPR-200/WebHome/1704864886951-793.jpg?rev=1.1||alt="1704864886951-793.jpg"]]
234 234  
235 235  |=Size (L x W x H)|30 x 25 x12cm
236 -|=Weight (with battery)| 1.9kg (2.5kg)
254 +|=Weight (with battery)| ~*~*1.9kg (2.5kg)
237 237  |=Battery|(((
238 -Lead-acid 12v, ~~7-9Ah
256 +Lead-acid 12v, ~~7Ah
239 239  
240 240  Rechargeable
241 241  )))
242 -|=Current Firmware|3.5a (Jan 2025)
243 243  
244 -[[image:terrasawr battery.jpg]]
261 +[[image:/xwiki/bin/download/Instrumentation/ANU%20LPR-200/WebHome/terrasawr%20battery.jpg?rev=1.1||alt="terrasawr battery.jpg"]]
245 245  )))
246 246  
247 247  
... ... @@ -249,26 +249,22 @@
249 249  (((
250 250  = LPR-200 Specs =
251 251  
252 -[[image:LPR 1.jpg]]
269 +[[image:/xwiki/bin/download/Instrumentation/ANU%20LPR-200/WebHome/LPR%201.jpg?rev=1.3||alt="LPR 1.jpg"]]
253 253  
254 -[[image:LPR 2.jpg]]
271 +[[image:/xwiki/bin/download/Instrumentation/ANU%20LPR-200/WebHome/LPR%202.jpg?rev=1.3||alt="LPR 2.jpg"]]
255 255  
256 -[[image:LPR 3.jpg]]
273 +[[image:/xwiki/bin/download/Instrumentation/ANU%20LPR-200/WebHome/LPR%203.jpg?rev=1.8||alt="LPR 3.jpg"]]
257 257  
258 258  |=Size (L x W x H)|42 x 34 x17 cm
259 -|=Weight (no battery)|5.5 kg
276 +|=Weight (with battery)|4.9 kg (7.3 kg)
260 260  |=Battery|(((
261 -NOW: Any 12v battery with tab connections that will fit (ex. the same TSAWR battery)
278 +LiFePo4 140Ah
262 262  
263 -DISCONTINUED: LiFePo4 140Ah Rechargeable (shown below).
280 +Rechargeable
264 264  )))
265 -|=Current Firmware|(((
266 -2.6a (old GPS modules) / 2.7a
267 267  
268 -Jan 2025
283 +[[image:/xwiki/bin/download/Instrumentation/ANU%20LPR-200/WebHome/LPR%20battery.jpg?rev=1.1||alt="LPR battery.jpg"]]
269 269  )))
270 -
271 -[[image:LPR battery.jpg]]
272 272  )))
273 -)))
274 -)))
286 +
287 +~)~)~)
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