PRINCIPLES OF OPERATION

The GMA405 Seismophone was originally developed to cater for the needs of cable fault location technicians where simplicity of use and high accuracy is of utmost importance in noisy environments.

The instrument is equipped with a number of filters, which greatly simplifies the acoustic pinpoint location of faults. It is also equipped with a number of other user-friendly features to simplify the procedure. Display of information is done in bar graph fashion.

The instrument embodies the very latest DSP (Digital Signal Processing) techniques, which greatly broadens the possibilities to upgrade and modify the instrument by simply updating the software.

This means that whenever a new technology is developed it will become available to you as the owner of the instrument. The acoustic amplifier employs five different filters to filter as much noise as possible before the signal is amplified. The magnetic amplifier is gain adjustable which allows the operator to attenuate the magnetic signal and then pinpoint exactly where the cable is. It also employs distance measurement techniques, which measure the time difference between the acoustic and magnetic amplifier.

The display is of a 128 x 64 graphic LCD display. Automatic Magnetic Gain Adjustment feature.

The instrument is set up in Auto Magnetic Gain mode by memorizing the cable depth. Auto power shut down feature – Instrument shuts down after 5 min of no user interaction.

Backlight also switches off after 30 seconds, if no user interaction.

Adret
GMA405
GROUND MICROPHONE

Ground Microphone Systems are available in a basic analogue and a high end digital range. In the higher end systems selectable filters and time of flight measurements are standard features.

SPECIFICATION

ACOUSTIIC AMPLIFIER
GAIN > 120db

MAGNETIC AMPLIFIER
GAIN > 120db

INDICATION
1280X800 HD Andoid Tablet

POWER SUPPLY
Detector Head: Built in battery
Tablet PC Built: Built in battery

BATTERY LIFE
Detector Head: 15hrs
Tablet PC: 15Hrs

FILTERS
Acoustic 100-1500Hz
Intelligent DSP Controlled

FAULT DIRECTION INDICATOR
Graphic Compass Indication
AUTO MUTE FUNCTION
Handle touch sensitive

DIMENSIONS
250X130X90mm

WEIGHT
AMPLIFIER 800 grams
MICROPHONE 1200 grams

Enclosure
IP65

ACCESSORIES

Lid : Aluminium with canvas bag for test cables
Test Cables : 5m HT lead with high current clamps
Earth Lead : 5m yellow/green
Mains Lead : 2m 3 core