This station was modified from a dm16 digitizer to a dm24 on 20060525. The result is greater amplitude resolution and dynamic range. There are now only 3 channels for each broadband (HH?) instead of the previous 6 channels (i.e. BL? channels are no longer necessary). The digitizer gain is thus changed from about 6.3 microVolts/count to about 1.127 microVolts/count.

Station Code: GNAR

Channels: HHZ, HHN, HHE, BLZ, BLN, BLE

Network Code: NM

Location: Lat: 35.9652 Lon: -90.0178 Ele: 71.0 m

Nearest town: Gosnell, AR and Blytheville, Ar

Opened: February 11, 2000

Sundries: Digitized on-site, digitally telemetered to local high school, simultaneously buffered locally and forwarded via internet (earthworm export/import) to Memphis. Data are packetized prior to being telemetered to 1024 byte packets. Actual number of samples per packet depend on compression.

Sensor Type: CMG40T

Nominally flat to velocity 30 seconds to 50 Hz.

Sensor Serial Number: T4235

Taps: Low gain, non-differential

Vertical

Poles (Hz)Zeros (Hz)
-23.56e(-3) +- 23.56e(-3)i0
-500
159

Normalization: -0.314

Horizontal:

Poles (Hz)Zeros (Hz)
-23.56e(-3) +- 23.56e(-3)i0
-500
159

Velocity Response:

Vertical: 795 V/m/s

North: 790 V/m/s

East: 803 V/m/s

Digitizer Type: DM16

Digitizer Serial Number: T4235/D0016

Digitizer resolution: 16 bits

gain (microV/count)

BLZ: 205.8

BLN: 205.5

BLE: 205.1

HHZ: 6.455

HHN: 6.424

HHE: 6.446

Sample rates:

HH? 100 sps

BL? 20 sps

Nominal system gain (excludes response function normalization) = (digitizer gain)/(velocity response)

HHZ: 8.1195e-9 m/s/count

HHN: 8.1316e-9 m/s/count

HHE: 8.0237e-9 m/s/count

BLZ: 2.5887e-7 m/s/count

BLN: 2.6013e-7 m/s/count

BLE: 2.5542e-7 m/s/count