Changes for page ANU Seismic Data Loggers
Last modified by robert on 2025/09/16 13:22
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... ... @@ -26,14 +26,6 @@ 26 26 (% class="wikigeneratedid" %) 27 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 28 29 -= GPS Considerations = 30 - 31 -GPS is required for the data to have accurate timestamps. A standard 3-5V 1575.42 Mhz coaxial cable works fine and can be found for relatively cheap (e.g. [[https:~~/~~/www.elecbee.com/en-3555-gps-antenna-bnc-male-for-garmin-gps-120120xl125-sounder-with-cable-2m) >>https://www.elecbee.com/en-3555-gps-antenna-bnc-male-for-garmin-gps-120120xl125-sounder-with-cable-2m]] 32 - 33 -The TerraSAWR has a built-in GPS but this doesn't work as well, especially if the logger is (wisely) buried. **The LPR does NOT have a built-in GPS antenna, so an external antenna is mandatory.** 34 - 35 -In a pinch, a severed or broken antenna can be mended back together relatively easily by non-experts. Even stripping the wire and twisting it back together by hand on site is possible! 36 - 37 37 = Data Card Formatting and Information = 38 38 39 39 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. ... ... @@ -40,8 +40,7 @@ 40 40 41 41 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. 42 42 43 -(% class="wikigeneratedid" id="HTheformatforANUSRSetup.txt2FLPR200swillbeasinglelineoftextthatlookslikethis:" %) 44 -The format for ANUSRSetup.txt / LPR200s will be a single line of text that looks like this: 35 +== The format for ANUSRSetup.txt / LPR200s will be a single line of text that looks like this: == 45 45 46 46 {{{XXX195G0100010034864 2 }}} 47 47 ... ... @@ -61,8 +61,7 @@ 61 61 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) 62 62 ))) 63 63 64 -(% class="wikigeneratedid" id="HTheformatforTSAWRloggersisshorter:" %) 65 -The format for TSAWR loggers is shorter: 55 +== The format for TSAWR loggers is shorter: == 66 66 67 67 (% class="box errormessage" %) 68 68 ((( ... ... @@ -81,8 +81,7 @@ 81 81 and seismometer serial number (9999). 82 82 83 83 84 -(% class="wikigeneratedid" id="HTheformattingprocessusingthelogger:" %) 85 -The formatting process using the logger: 74 +== The formatting process using the logger: == 86 86 87 87 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 88 88 ... ... @@ -115,8 +115,8 @@ 115 115 116 116 This menu also displays the firmware version, battery, external, and solar voltages, and the temperature of the system. 117 117 118 -* Check that all//Initialisation Parameters//are marked as successful.119 -* Check that solar voltage is above 10 V i nthe software,orpreferrably physicallycheckthatthe battery'svoltageis increasingvia a DMM.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. 120 120 121 121 == Live Seismometer Data == 122 122 ... ... @@ -130,7 +130,7 @@ 130 130 131 131 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. 132 132 133 -* Check that the station is connected to satellites . 3 or more should be perfectly adequate to keep time.122 +* Check that the station is connected to satellites 134 134 135 135 == SD Information == 136 136 ... ... @@ -163,7 +163,7 @@ 163 163 164 164 (% class="box errormessage" %) 165 165 ((( 166 - Again,ensure the 'RECORD ON RESTART' option is marked with a cross(the default setting).This ensures that the logger will record any time it receives enough power!155 +NOTE: Ensure the 'RECORD ON RESTART' option is marked with a cross. 167 167 ))) 168 168 169 169 (% class="wikigeneratedid" %) ... ... @@ -179,57 +179,30 @@ 179 179 180 180 = Instrument Response = 181 181 182 -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 (for better or worse!).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. 183 183 184 -In the logger's menu, 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. 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}} 185 185 186 - //(The600+Stage3SINCcoefficientsduringtheinitial 1024k>16kdecimationwereleftoffastheysloweddowntheprocessx10 and contributeatmost0.3db amplitude and 0.31msphasedelaydiscrepancies,andprimarilyonlytofrequenciesnear the nyquist.Ifforsomereason youwanttoaddthisphasemanuallywecan share theparameterswith you.)//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. 187 187 188 - Youightnoticethat theresponseinformationmaycomeintwoversions.Theresponse fromour website (seelinkbelow) includesthe2nd "sensorgain"stageforclarity.e.g.here isTrillium Compact 120 & ANU Loggerresponse179 +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') ). 189 189 190 -##Channel Response 191 - From M/S (Velocity) to COUNTS () 192 - Overall Sensitivity: 3.95452e+08 defined at 1.000 Hz 193 - 8 stages: 194 - Stage 1: PolesZerosResponseStage from M/S to V, gain: 754.3 195 - Stage 2: ResponseStage from V to V, gain: 0.25 196 - Stage 3: CoefficientsTypeResponseStage from V to COUNTS, gain: 2.09715e+06 197 - Stage 4: FIRResponseStage from COUNTS to COUNTS, gain: 1 198 - Stage 5: FIRResponseStage from COUNTS to COUNTS, gain: 1 199 - Stage 6: FIRResponseStage from COUNTS to COUNTS, gain: 0.99998 200 - Stage 7: FIRResponseStage from COUNTS to COUNTS, gain: 1## 201 201 182 +[[Amplitude and phase response for ANU logger at 50 Hz>>image:ANU_50hz_response.png]] 202 202 203 - However,if retrievingfrom AusPassorIRIS, the2nd "sensor gain"stageis combinedwiththeloggergain. This has no affect,butyoumay detect that the former Stage 2 V->V ResponseStage has beenmerged into the Stage 3 gain.184 +[[Amplitude and phase response for ANU logger at 100 Hz>>image:ANU_100hz_response.png]] 204 204 205 -##Channel Response 206 - From M/S (Velocity) to COUNTS () 207 - Overall Sensitivity: 3.9546e+08 defined at 1.000 Hz 208 - 6 stages: 209 - Stage 1: PolesZerosResponseStage from M/S to V, gain: 754.3 210 - Stage 2: CoefficientsTypeResponseStage from V to COUNTS, gain: 524288 211 - Stage 3: FIRResponseStage from COUNTS to COUNTS, gain: 1 212 - Stage 4: FIRResponseStage from COUNTS to COUNTS, gain: 1 213 - Stage 5: FIRResponseStage from COUNTS to COUNTS, gain: 0.99998 214 - Stage 6: FIRResponseStage from COUNTS to COUNTS, gain: 1## 215 215 187 +[[Amplitude and phase response for ANU logger at 250 Hz>>image:ANU_250hz_response.png]] 216 216 217 -For the most part, the data logger response essentially flat when the samplerate output is set to 100 Hz or less and for seismological purposes is likely to be impossible to detect below 20 Hz regardless. 218 218 219 - Instrument response can be downloaded from IRIS[[Nominal Response Library>>https://ds.iris.edu/ds/nrl/]]ifneedbe, or [[directly from us>>http://auspass.edu.au/data/logger_response]],orbydownloadingtheesponseofan equivalentsensorat AusPass (e.g. get_stations(level='response') ).190 +[[Amplitude and phase response for ANU logger at 1000 Hz>>image:ANU_1000hz_response.png]] 220 220 221 221 222 -[[ Amplitude andphaseresponseforANUlogger at50Hz>>image:ANU_50hz_response.png||data-xwiki-image-style-alignment="center"height="356" width="475"]]193 +[[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"]] 223 223 224 -[[Amplitude and phase response for ANU logger at 100 Hz>>image:ANU_100hz_response.png||data-xwiki-image-style-alignment="center" height="355" width="473"]] 225 - 226 -[[Amplitude and phase response for ANU logger at 250 Hz>>image:ANU_250hz_response.png||data-xwiki-image-style-alignment="center" height="359" width="479"]] 227 - 228 -[[Amplitude and phase response for ANU logger at 1000 Hz>>image:ANU_1000hz_response.png||data-xwiki-image-style-alignment="center" height="367" width="489"]] 229 - 230 - 231 -[[Huddle test comparing a Trillium Compact 120 + TerraSAWR vs a Trillium Compact 120 + Nanometrics Centaur (M8.AUANU) at 100 Hz>>image:TC120_ANU_vs_CENTAUR.png||data-xwiki-image-style-alignment="center"]] 232 - 233 233 = ANU TerraSAWR (Gen 3, FW 3.5a, 2014- current) = 234 234 235 235 Earliest known model is dated July 2014 (though first deployed in 2019) and our current flagship model. Lightweight and small. ... ... @@ -272,14 +272,6 @@ 272 272 273 273 274 274 275 - 276 - 277 - 278 - 279 - 280 - 281 - 282 - 283 283 (% class="box" %) 284 284 ((( 285 285 = TerraSAWR Specs = ... ... @@ -330,13 +330,4 @@ 330 330 [[image:LPR battery.jpg]] 331 331 ))) 332 332 ))) 333 - 334 - 335 - 336 - 337 - 338 - 339 - 340 - 341 - 342 342 )))