Geophone

GS-20DH
gs-20dh.html


GS-20DH
Feature

Clean response to 400 Hz
High frequency, high output
Works in any position
Low cost, long life
Full one year warranty
General Description

The GS-20DH is a high frequency, high output, digital grade geophone designed for long life and reliable service. The Geo Space manufacturing process includes checking of geophone operating parameters with the ATS, an automated computerized test system.
Natural frequencies are 28 to 40 Hz. Coil resistances are 365, 600 and 1000 ohms. Open circuit damping is 57% for the 28 Hz unit and 40% for the 40 Hz unit. The PC-21 Land Case is used with the GS-20DH geophone.
Specifications

Natural Frequency : 28 and 40 Hz }5%

Frequency Tolerance with Tilt : } 1.6 Hz @ 25 (28 Hz) } 2.2 Hz @ 25 (40 Hz)

Typical Spurious Frequency : >400 Hz

Standard Coil Resistance @ 25 C : 600 Ohms }5%

Intrinsic Voltage Sensitivity with 600 Ohm Coil : 0.90 V/in/sec (.354 V/cm/sec) }10%

Normalized Transduction Constant (V/in/sec) : 0.037(sq.root of Rc)

Open Circuit Damping : 0.57 @ 28 Hz & 0.40 @ 40 Hz }10%

Optional Coil Resistances : 365, 1000 Ohms }5%

Moving Mass : 7.1 g }10%

Typical Case to Coil Motion P-P : 0.06 in (.15 cm)

Harmonic Distortion with driving velocity of 0.7 in/sec (1.8 cm/sec) P-P : 0.2% or less @ fn

Dimensions:

Height: (less terminals*) : 1.32 in (3.35 cm)

Diameter: 1.06 in (2.69 cm)

Weight: 3.5 oz (99)

* Terminal Height is .16 inches

Chart for Seismic Detector Response Curve Output VS. Frequency (GS-20DH @ 28 Hz @ 365ohms and 600ohms, GS-20DH @ 40 Hz@ 365ohms and 600ohms).

Cases Available
PC-21 Land Case

Specifications are subject to change without notice.