Shackleford-Gundersen Seismometer Electronics Board
Last Updated: 04/26/06Please note that this board is no longer in production
Please note that this board is no longer in production
Inputs:
The board has two RCA jack inputs (the lower right hand jacks in the photo above)
that are connected to the receiving antenna plates mounted inside the sensor. The
first amplifier stage, the summing amp, is designed around a low noise high performance
op-amp.
Outputs to Sensor:
The board supplies two signals that go to the sensors. It supplies a low impedance output
signal used to drive the damping coil, and, a regulated +5 volt signal used to power the TTL
oscillator mounted on the pendulum. The connector used for the damping coil and
the oscillator power is a 4 pin .156 Molex connector. This connector is located near the upper
right hand corner in the photo above.
Output Signals:
The board has two output signals that go to an
Analog to Digital Converter Board or chart
recorder. The Low Frequency Port integrates the data from the sensors making it
more sensitive to the long period waves produced by teleseismic (distant) earthquakes.
The High Frequency Port bypasses the integrator and is used for local or regional
events. The output signal RCA jacks can be seen in the bottom center of the board in the
photo above. Both outputs are designed to drive +- 10 volts maximum into a 600 ohm load,
and, are able to drive over 100 feet of coax cable.
Tilt LED:
The board has a two color LED (Light Emitting Diode) that will turn either red or green
indication that the sensor is tilting too much.
Power Requirements:
The board requires a 24 to 28 volt center tapped transformer with 300ma, or more, of output
current. I have a wall mounted transformer that I sell that can power up to two boards.
Board Dimensions:
I also have the following parts available to help you build your SG sensor:
5 3/4 x 7 3/4 inches or 14.5 x 19.7 cm.
Schematic of the SG Electronics Board:
Cost:
The SG Electronics board can be ordered with either the Low Frequency or High Frequency
port or with both ports. The board with one port (either High or Low) costs $125.00.
A complete board with both output ports costs $145.00. I'm selling the board built
and tested without a box to keep the cost down. A wall mounted power supply that will
work with this board costs $15.00. Please add $8.00 for shipping and insurance.
Cost: $20.00 each
Cost: $7.50 each
Cost: $45.00 for two antennas and one transmitter plate that can be mounted on the pendulum.
Cost: $6.00 each
Additional Information:
