Last modified by robert on 2026/02/27 19:58

From version 104.2
edited by robert
on 2026/02/17 12:37
Change comment: There is no comment for this version
To version 103.1
edited by robert
on 2026/02/16 17:55
Change comment: There is no comment for this version

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... ... @@ -427,14 +427,12 @@
427 427   'gain':1,
428 428   'sensitivity': 257019225.55108312}
429 429  
430 -[[X axis is samples (.01 s), Y axis is velocity (m/s), 0.5-5 Hz filter>>image:IGU16_Z_huddle.png]]
430 +[[X axis is samples (.01 s), Y axis is velocity (m/s)>>image:IGU16_Z_huddle.png]]
431 431  
432 -[[X axis is samples (.01 s), Y axis is velocity (m/s), 0.5-5 Hz filter>>image:IGU16_N_huddle.png]]
432 +[[X axis is samples (.01 s), Y axis is velocity (m/s)>>image:IGU16_N_huddle.png]]
433 433  
434 434  == IGU 16-1C ==
435 435  
436 -The 1C nodes seem to have a slightly different response to the 3C (TBA)
437 -
438 438  == BD3C-5 ==
439 439  
440 440   'BD3C': {'poles':[(-1720.4+0j), (-1.2+0.9j), (-1.2-0.9j)],
... ... @@ -442,13 +442,11 @@
442 442   'gain':1.69726e-05,
443 443   'sensitivity': 702651512.6046528}
444 444  
445 -*image TBA but they have been created in the past~-~- we are 100% confident our published responses are correct
446 -
447 447  == Horizontal noise & how to avoid ==
448 448  
449 449  The 5 Hz nodes are susceptible to horizontal noise due to the placement of geophones in the units, **but this can be mitigated by completely burying the units flush with the ground.** In the below example, the node was set on the floor of our basement set on its plastic carrying case support. As such the amount of horizontal noise noticeably increases above ~~ 10Hz.
450 450  
451 -[[Power spectrum huddle test vs a CMG-6TD (S1) and TC120/Centaur combo. The N and E channels have excess noise above 10Hz due to "sticking up" out of the ground.>>image:IGU16_spectrum.png]]
447 +[[Power spectrum huddle test vs a CMG-6TD (S1) and TC120/Centaur combo, all filtered 0.5-5 Hz. The N and E channels have excess noise above 10Hz due to "sticking up" out of the ground.>>image:IGU16_spectrum.png]]
452 452  
453 453  = **Cleaning** =
454 454