Users Manual

Geophysical Survey Systems, Inc. 1 GHz Horn Antenna
Model 41000SA
MN30-903 Rev G 8
Signal Position
Place the antenna on the ground and use the Automatic Signal Position selection. The system will servo
and place the direct coupling pulse at the top of the time range window.
To test that you have the correct position, raise the antenna off the ground and you will observe on your
system that the antenna transmit pulse will separate from the reflection from the ground. The higher that
you raise the antenna, the further apart will be the two pulses.
To assure that the direct coupling pulse (time zero) is recorded the user should place the signal Position
servo in the manual mode. The signal should then be moved down in the time range window until the
entire surface pulse is visible and there is some ‘dead time’ or flat trace visible above the direct coupling
pulse in the time range window.
Gain Check
The surface pulse should be about 2/3 the width of the screen. If it is greater, reduce the Gains manually.
If the signal appears too small you can manually increase the Gains, but the first gain point should never
exceed 10dB, the last gain point should not exceed 65dB.
Specifications
Center frequency: 200 MHz
Pulse duration: 5 ns
Depth of penetration: 0-30 ft depending on dielectric permittivity
Size of sensor: 12x12x6.5 inches (60x60x30cm)
Weight of sensor: 39 lbs (17.72 kg)