Question about settings.json

Technical Support
1

Hi Ian.
Under default settings in .json file. In couple of two hours there was 2 local EQ magnitude 2.0 but system did not show them. Is there a way that in .json file could be disabled STA and LTA parameters or?

“alert”: {
“enabled”: true,
“highpass”: 1,
“lowpass”: 10,
“deconvolve”: false,
“units”: “VEL”,
“sta”: 6,
“lta”: 30,
“threshold”: 100 ,
“reset”: 90,
I am playing with this numbers but no luck. I would like to disable STA and LTA numbers what should I do?
Thanks Marco

2

You can disable the STA / LTA trigger by setting “enabled”: false,

Your threshold and reset are very high for the trigger algorithm here…the max STA/LTA will never get that high. Depending on how quiet or noisy your site is, you may want to set a threshold between about 1 and 4, and a reset of between 0.5 and 1.

3

These threshold and reset values change nonlinearly with the filter parameters, meaning the setting that works for a filter between 1 and 10 Hz will be very different than an unfiltered alert stream, or even one that is lowpassed below 10 Hz. Here are the settings I use personally at my house, which is built on a concrete slab on a landslide deposit (my shake sits on the slab):

"alert": {
    "enabled": true,
    "channel": "HZ",
    "highpass": 0.5,
    "lowpass": 8,
    "deconvolve": false,
    "units": "VEL",
    "sta": 6,
    "lta": 30,
    "threshold": 0.3,
    "reset": 0.2,
    "exec": "eqAlert",
    "win_override": false},