Instruction Manual Model GA-52Cx Manufactured By Schonstedt Instrument Company 100 Edmond Road Kearneysville, WV 25430 (304) 725-1050 Fax (304) 725-1095 Web: http://www.schonstedt.com E-mail: info@schonstedt.com Preface The Model GA-52Cx Magnetic Locator is a product of over forty-five years of experience in producing the world’s finest flux-gate magnetometers and magnetic detectors for aerospace, military and civilian applications.
Table of Contents Operation Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Turn-On, Volume and Sensitivity Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Search Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Operation Introduction The GA-52Cx Magnetic Locator detects the magnetic field of a ferromagnetic object. It responds to the difference in the magnetic field between two sensors spaced about 20 inches apart. The response is a change in the frequency of the signal emitted by the piezoelectric speaker. Figure 1 illustrates an application of the locator in which it is used to detect an iron marker of the type used for property line identification.
Search Procedure Set the sensitivity control to position 2 (Normal Range) and grasp the locator as illustrated. Because the upper sensor is located near where the locator is usually held, wrist watches may produce unwanted changes in the tones frequency. (Remove your wrist watch or hold the locator in the other hand). Keep the locator away from your shoes, since they might contain magnetic material. To obtain maximum area coverage, the locator should be swept from side-to-side.
Application Notes Basic Signal Patterns Figure 4. Signals from Vertical and Horizontal Targets After you have detected the presence of a target, hold the locator vertically and move it back and forth in an “X” pattern. The peak signal occurs directly over a vertical target, and over the ends of a horizontal target. The “X” pattern is ideal for pinpointing small objects.
SIGNAL ABOVE GROUND SIGNAL AT GROUND CORNER MARKER SMALL BOLT Figure 6. Raising the Locator Eliminates Unwanted Signals Strongly Magnetized Markers A strongly magnetized marker at or near the surface may provide location information that is misleading. The heavy line in Figure 7 represents the variations in tone frequencies when the locator is moved over the marker. When moving the instrument from A to B, the frequency of the tone increases and then suddenly decreases at B.
This phenomenon is explained by the fact that the locator is sensitive to the magnetic field components parallel to its long axis. At points B and C the field is perpendicular to the locator so no high frequency is produced at these points. Locating Manholes, Septic Tanks and Well Casings The magnetic field is strongest at the edge of a shallow manhole cover. You can easily trace the edges of covers near the surface. Locating depth ranges up to 10 feet.
Locating Objects under Snow or Water and Tracing Barbed Wire The locator can be used in flooded areas, just keep the electronic unit out of the water. Snow poses no problem. Thrust the locator into the snow as deep as necessary to locate the target. Figure 11. Locating Objects Under Snow or Water You can often trace barbed wire (from old fence lines) buried just beneath the surface. Even if the wire is only a trail of rust it can still be detected near the surface.
Searching Areas Along a Chain Link Fence Searching in the vicinity of a chain link fence requires a reduced sensitivity setting and also some control over the orientation of the locator. As illustrated in Figure 13, position the locator horizontally, with its long axis perpendicular to the fence. This ensures that the upper sensor is kept away from the fence. Figure 13.
Locating Valve Boxes Both the valve and its casing, when iron, provide strong magnetic fields that make them easy to locate. Plastic enclosures containing magnets are easily located at depths of 10 feet or more. Figure 15. Locating Valve Boxes and Casings Locating Cast-Iron Pipes As illustrated in Figure 16, cast-iron pipes produce the strongest magnetic signals at their joints. Figure 16. Signal Patterns Provided by Cast-Iron Pipes The initial search should be performed as follows: 1.
Locating Steel Drums As shown in Figure 17, the GA-52Cx’s signal pattern will vary depending on the vertical or horizontal orientation of the drum and also how deep it is buried. A fifty-five gallon drum can be located at depths of up to 10 feet. Figure 17. Signal Patterns Provided by Steel Drums Additional Applications 1. The military and many local and state police departments use the GA-52Cx to detect buried ordnance and discarded weapons. 2.
Maintenance The GA-52Cx is designed and built to give trouble-free operation. Normally, maintenance is limited to the occasional replacement of batteries. In the event that a malfunction does occur, refer to the trouble-shooting guide on page 11. It lists a few problems that can generally be corrected in the field so that you will be able to continue using the locator without interruption. Replacement of Batteries The GA-52Cx is powered by two alkaline 9-Volt batteries.
Troubleshooting Guide Symptom No response Possible Cause How to Check How to Fix Dead batteries Replace - Batteries not making contact Check for contact corrosion Clean contacts Battery leakage Do not remove batteries* Return unit to factory Intermittent Batteries not making good contact Check for corrosion Clean contacts Uncontrollable screaming Weak batteries Replace - *Most battery manufactures’ warranties cover the cost of repair or replacement of any device damaged by their batter
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LIMITED WARRANTY The Schonstedt Instrument Company (Schonstedt) warrants each product of its manufacture to be free from defects in material and workmanship subject to the following terms and conditions. The warranty is effective for 7 years (with the return of the Customer Registration Card) after the shipment by Schonstedt to the original purchaser.
