Schonstedt Instrument GA-72Cd User manual

Instruction Manual
Model GA-72Cd
Magnetic Locator
Manufactured By
Schonstedt Instrument Company
Preface
The Model GA-72Cd

Magnetic Locator is aproduct of overforty-six years experiencein producing the world’s finest flux-gate magne-
tometers and magnetic detectors for aerospace, military and civilian applications. The GA-72Cd  incorporates
the
knowledge obtained from manufacturing under the most rigid quality control standards. The heart of the GA-72Cd  is its
patented
Schonstedt HeliFlux  magnetic field sensors. These sensors, acknowledged to be the world’s finest, make possible the
unequalled
performance
of the locator.
December 1998
Schonstedt Instrument Company
Provided By:
Global Detection Systems
Specializing in Professional Detection Systems Since 1968
We Sell and Rent Equipment Internationally
Visit Us on the Web at: GlobalDetection.net
Call Us: 1-918-663-9492 or USA TOLL FREE: 1-800-261-8211
Fax Us: 1-918-663-3015
Email Us: [email protected]
Visit Our Headquarters:
2517 S. Memorial Dr., Tulsa, OK 74129 USA

Table of Contents
Operation
Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Turn-on, Sensitivity and Volume Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Battery Level Indication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Audio Ouput Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Search Procedure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Application Notes
Basic Signal Patterns. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Strongly Magnetized Markers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Correct Stake Orientation is Important . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Locating Manholes, Septic Tanks and Well Casings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Locating Objects under Snow or Water and Traced Barbed Wire. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Searching Areas along a Chain Link Fence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Locating Valve Boxes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Locating Cast-Iron Pipes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Locating Steel Drums . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Locating Nonmetallic Duct and Cable. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Locating Ordnance and Weapons. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Additional Applications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Other Notes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Data Logger Output. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
14
Maintenance
Replacement of Batteries. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Troubleshooting Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
GA-72Cd Repair Parts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Service Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
17
Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
17
Warranty/Shipping Information
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Schonstedt Instrument Company

OPERATION
Introduction
The Model GA-72Cd Magnetic Locator detects the magnetic field of ferromagnetic objects. It responds to the difference in the
magnetic field between two sensors which are spaced about 14 inches apart. The GA-72Cd is unique because it provides an
audio
signal, and visual indications of both signal strength and polarity. Although most objects can be located using either of the
indications,
simultaneous use of both types will help you pinpoint a target and determine its orientation and identify magnetically detectab
le
nonmetallic duct and cable.
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 identifi-
cation. As shown, the magnetic field of the iron marker is stronger at sensor Athan it is at sensor B. As a result, the frequency of
the
audio signal is higher than the idling frequency, 40 Hz, which exists when the field strength is the same at both sensors. This
stronger
signal also causes the digital indication to peak in either the positive or the negative direction when the audio signal is at its
highest
frequency.
Figure 1. Detecting Magnetic Field of an Iron Marker
When shipped, the locator is set to provide an audio signal which is heard as long as the instrument is turned on. If desired, you can
change this to an audio signal which is heard only when the instrument is within detection range of an object by using the
internal
Audio Output Switch as described on page 4 of this manual.
Schonstedt Instrument Company
1

Turn-On, Sensitivity and Volume Settings
Turn on the GA-72Cd by rotating the On/Off-Sensitivity control knob clockwise to position 1. This sets the sensitivity to what is
referred to as the Normal Range (the Lmeter indication). You can increase the sensitivity by rotating the Sensitivity control
clockwise
to select
M
,
H
, or
XH
settings as indicated on the meter’s GAIN display. Adjust the Volume control for the desired audio output level.
ON/OFF
Sensitivity
Levels
Headset Jack
(also output for
Data Logger)
Volume Control
Magnetic Field
Polarity
Signal Strength
(in differential milli-
gauss)
Selected
Sensitivity
Level
Indicator
Battery Charge
Indicator
Negative Polarity
Expanding Bar Graph
Positive Polarity
Expanding Bar Graph
Figure 2. Control and Meter Indications
Battery Level Indication
The meter’s BATT indication displays the batteries’ voltage level. As shown in Figure 3, when all four segments are black the voltage
level is between 100% and 25% (up to 60 hours of operation with intermittent usage). As the voltage decreases, the number of b
lack
segments decreases. Battery life varies with usage and the ambient temperature. Cold temperatures reduce battery life. Low temper
-
atures may result in only two or three segments being black. This could be temporary and all segments will change back to black
as
the temperature increases.
100 to 25%
25 to 20%
20 to 10%
10 to 1%
Figure 3. Battery Voltage Status Indications
Schonstedt Instrument Company
2

Audio Output Selection
All GA-72Cds are shipped from the factory with the Audio Output Switch set to
“B”
. This provides an audio signal that is always
present. If you prefer not to hear a signal until the locator is within detection range of a target, set the switch to
“A”
.
Audio Signal with Output Switch set to “A”
No audio signal is heard until the GA-72Cd comes within detection range of a ferromagnetic object. As you
move the locator across the object, frequency of the signal does not change but unit increases in volume over
the object, then decreases in volume and turns off when the locator is moved out of range.
NOTE: If you put the GA-72Cd down without turning the Sensitivity/Power switch to Off, the
“power-on monitoring feature” (designed to conserve battery life) will initiate a
beeping
audio-alert signal after 15 seconds.
Audio Signal with Audio Output Switch set to “B”
As you move the GA-72Cd across a ferromagnetic object, the 40 Hz idling signal, which is always present,
increases in frequency, peaks when the locator is directly over the object and then decreases to 40 Hz.
Regardless of which switch setting, the indication of signal strength and the polarity on the meter will always peak (positive or nega-
tive) when the locator is directly over a ferromagnetic object.
As shown, the cover must be removed to change the setting of the Audio Output Switch.
Figure 4. Location of Audio Output Switch
Schonstedt Instrument Company
3

Search Procedure
Set the On/Off-Sensitivity control for
L
and grasp the locator as illustrated. Because the upper sensor is near the locator’s handle, wrist-
watches may produce unwanted changes in the audio
signal
and in the meter indications, and should be removed.
Keep
the locator away from your shoes since they might
contain
magnetic material. To obtain maximum area
coverage,
sweep the locator from side to side. When the locator comes
within range of an iron object, the audio signal will peak,
the
bar graph will expand positive or negative, and the
digital
readout will peak as shown in Figure 6.
Figure 5. Searching With the Locator
When the GA-72Cd is positioned directly over a vertical pipe, the audio and digital indications will peak. The expanding bar graph
and digital readout may be either a positive or negative level.
Figure 6. The Meter’s Polarity Indications Help to
Determine Target Orientation
The audio signal, bar graph and digital indications peak over each end of a horizontal pipe. One end is positive, the other is negative.
This will help you to distinguish between two vertical pipes or one horizontal pipe. Usually two vertical pipes buried in close prox
-
imity will produce digital indications with the same polarity.
Schonstedt Instrument Company
4

APPLICATION NOTES
Basic Signal Patterns
Audio signal peaks
directly over vertical
target. Visual
indications
also peak as either
polarity.
Audio signal peaks over each end
of a horizontal target. Visual indica-
tions peak positive over one end
and negative over the other end.
+
or
-
+
-
Figure 7. Signals from Vertical and Horizontal Targets
After you have detected the presence of a target, hold the locator vertically and slowly move it back and forth in an “X” pattern while
observing the digital readout. The value of the number will be highest when the locator is directly over a target, and over the ends
of
a horizontal target. The “X” pattern is ideal for pinpointing small objects. A 1-1/4 inch PK nail buried up to 8 inches can be
located
so precisely with this technique that it can be uncovered using a 1/2 inch star drill.
Figure 8. “X” Pattern provides Precision Locating
If you are looking for a corner marker and detect two or three signals in the same general vicinity, raise the locator several inches above
the ground or reduce the sensitivity setting before you get a shovel. Any signal that disappears when the locator is held higher is prob
-
ably coming from a shallow target. The signal from a rusty bolt or other small item (see Figure 9.) decreases much faster with
distance
than the signal from a larger target such as a 18-inch length of 3/4 rebar which can be located at depths up to 7 feet.
Schonstedt Instrument Company
5

AUDIO SIGNAL HIGHER ABOVE GROUND
+ OR -
AUDIO SIGNAL CLOSE TO GROUND
+ OR -
SMALL BOLT
CORNER MARKER
Figure 9. Raising the Locator Eliminates Unwanted Signals
Strongly Magnetized Markers
A strongly magnetized marker at or near the surface provides a weaker indication on both sides of the marker that could be mistaken
for the marker.
The heavy line in Figure 10 represents the increase and decrease in the audio and digital indications as you move the locator over a
marker. Between points Aand Bthe signals increase slightly and then decrease. Just beyond Bthe signals increase rapidly,
peaks
directly over the marker and then decreases at point C. From Cto Dthe signals increase and decrease again. So if you do not
move
the locator completely across the marker you might assume that the weaker indication on either side of the marker is its location.
AUDIO SIGNAL
A
+ OR -
B
0
+ OR -
C
0
D
+ OR -
IRON PIPE
Figure 10. Signal Pattern from a Strongly Magnetized Marker
The two weaker indications occur because the locator is extremely sensitive to the magnetic field components parallel to its long axis.
At point
B
and
C
the field is perpendicular to the locator so no peak audio of digital indications are produced at these points.
Schonstedt Instrument Company
6

When Placing Stakes Correct Orientation is Important
For checking purposes, the orientation of the pin relative to the locator is shown in Figure 11. Check
the pin with one orientation. Then rotate the pin 180°. The orientation which gives the largest
reading
is the one that should be used. This reading would be positive in the Northern Hemisphere, and nega
-
tive in the Southern Hemisphere (Australia, New Zealand, etc.)
An iron pin has two types of magnetization. One is the magnetization induced by the Earth’s magnetic
field. The induced magnetization is always downward in the Northern Magnetic Hemisphere
and
produces a positive output no matter which end of the stake is driven into the ground. The other
type
of field is the permanent magnetization which is fixed to the pin. For maximum detection, the
stake
should be driven into the ground such that the permanent magnetization is in the same direction as
the
induced magnetization.
Figure 11. Checking a
Stake’s Orientation
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 8 feet.
The great length of a well casing provides a strong field at the surface that makes it easy to locate casings buried up to 15 feet deep.
Figu
re 12. Locating Manhole Covers
Figure 13. Locating Water
Well Casings
Schonstedt Instrument Company
7

The GA-72Cd can be used to precisely locate the metal handles or reinforcing bars on septic tank covers at depths up to 4 feet.
+ OR -
AUDIO SIGNAL
+ OR -
Figure 14. Signal Patterns Provided by Septic Tank Covers
Locating Objects Under Snow or Water and Tracing Barbed Wire
The locator can be used in snow or in flooded areas - just keep the electronic unit out of the snow or water.
SNOW BANK
Figure 15. 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. Tip the locator a little lower than usual - but not parallel with the ground.
Examine trees for bench marks and bits of embedded barbed wire. Hold the locator parallel with the direction of the wire.
Schonstedt Instrument Company
8

Figure 16. Tracing Barbed Wire from Old Fence Lines
Searching Areas Along a Chain Link Fence
Searching in the vicinity of a chain link fence requires
a reduced sensitivity setting and some control over
the
orientation of the locator. Position the locator horizon
-
tally with its long axis perpendicular to the fence
as
illustrated in Figure 17. This insures that the
upper
sensor is kept away from the fence.
Figure 17. Searching in the Vicinity of a Chain Link Fence
Perform the search by slowly moving the locator
forward along the fence while also moving it to
the
right and to the left. This technique allows you
to
search an area several feet wide as you move
forward.
Listen for an abrupt drop in the signal (as shown by
the
null in Figure 18) that will occur when the
lower
sensor, located 1-5/8 inches from the end of the locator
,
is directly over the stake. Any variation in the
position
of the locator will produce an abrupt rise in
the
frequency of the signal.
+
SIGNAL NULL WITH
LOCATOR AS SHOWN
1- 5/8
Figure 18. Placement of Locator while Searching along a Chain Link Fence
Schonstedt Instrument Company
9

Locating Valve Boxes
Both the valve and its casing, when iron, provide strong magnetic fields which
make them easy to locate. Plastic enclosures containing magnets are
easily
located at depths of 6 feet or more.
Locating Cast-Iron Pipes
Figure 19. Locating Valve Boxes and Casings
As illustrated in Figure 20, cast-iron pipes produce the strongest magnetic signals at their joints.
+
or
- +
or
-
1-11/
2
FEET
Figure 20. Signal Patterns Provided by Cast-Iron Pipes
The initial search should be performed as follows:
1. Set the Sensitivity control for maximum (XH indication).
2. Hold the locator vertically approximately 1 to 1-1/2 feet above the surface.
3. Walk along without turning or tilting the locator.
4. Mark the locations where the maximum signal levels occur.
5. Return to an area of maximum signal strength and hold the locator several inches
above
the surface. The sensitivity will probably have to be reduced during this second pass.
Four-inch pipes can be located at depths up to 8 feet.
Schonstedt Instrument Company
10

Locating Steel Drums
As shown in Figure 21, the GA-72Cd’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 up to 8 feet.
SIGNAL PATTERN FOR DRUMS BURIED APPROXIMATELY 4 TO 8 FEET
+or -
SIGNAL PATTERN FOR DRUMS BURIED APPROXIMATELY 4 FEET OR LESS
+
or
- +
or
- +
or
- +
or
-
Figure 21. Signal patterns provided by steel drums
Locating Magnetized Nonmetallic Duct and Cable
Schonstedt’s patented technology for incorporating magnetic materials into nonmetallic duct and cable makes it easy to locate these
objects at various depths as listed in Table A.
This technology also provides “magnetic signatures” consisting of positive and negative polarities that alternate at specific intervals.
Different intervals (see Table A) provide each of the three categories of duct and cable with a unique magnetic signature used for posi
-
tive identification. Magnetic signatures also help to distinguish nonmetallic duct and cable from cast-iron or steel pipe.
Table A. Magnetic Signatures and Detection Depths for Magnetized
Metallic Duct and Cable Applications
APPLICATION
CATV
(duct/cable)
MAGNETIC SIGNATURE
(Meter alternates
between
positive and negative)
Every 4 feet
DETECTION
DEPTH*
Up to 4 feet
Telephone
Every 6 feet
Up to 5 feet
Electrical (duct)
Every 7 feet
Up to 5 feet
* Sensitivity set to XH
Schonstedt Instrument Company
11

As shown in Figure 22, a magnetized nonmetallic fiber optic cable is easily identified by the GA-72Cd’s visual indication which
changes from positive to negative every six feet along with the audio signal which also peaks every six feet.
+
0
-
VISUAL SIGNAL
AUDIO
SIGNAL
0
+
6 feet
6 feet
Figure 22. Magnetically Detectable Nonmetallic Cable
Provides a Unique Magnetic Signature
Locating Ordinance and Weapons
The versatile, lightweight, cost-effective GA-72Cd is also designed to
aid EOD technicians and law enforcement officers during area s
earch
operations.
+
or
-
+ -
Basic signal patterns from vertical and horizontal targets help to
determine target orientation.
A 175mm projectile can be located up to 5 feet deep.
Schonstedt Instrument Company
12

An 81mm mortar can be located up to 12 inches deep.
MK81 Low drag bombs can be located up to 9 feet deep.
A hunting knife under water can be located in up to 16 inches of silt.
A discarded hand gun can be located up to 12 inches deep
Additional Applications
1. People drilling in an area where hazardous materials might be encountered should use the
GA-72Cd to search the area prior to drilling. Other Schonstedt gradiometers are
available
that can be lowered down the drill hole for periodic checks as drilling progresses.
Other Notes
1. A burbling sound indicates the presence of an energized power line. This will not influence
the meter indication unless associated with a magnetic structure.
2. The instrument will not respond to nonmetallic materials such as gold, silver, copper, brass
and aluminum.
Schonstedt Instrument Company
13

DATA LOGGER OUTPUT
The headset jack also provides an analog output signal for input to a data logger. This +/-4 volt signal varies in proportion to signal
strength and is accessible by wiring a standard stereo plug as illustrated in Figure 23.
Gnd
DC Out
(+/- 4 V FS)
Tone
Figure 23. Stereo Plug Connections for Analog Output Signal
MAINTENANCE
The GA-72Cd is designed and built to give trouble-free operation. Normally, maintenance is limited to the occasional replacement of
the batteries. In the event a malfunction does occur, refer to the Troubleshooting Guide on page 15 for a few problems that you
can
correct in the field.
Replacement of Batteries
The GA-72Cd is powered by two 9-volt lithium batteries which have a shelf life of ten years, and provide twice the operating life of
alkaline batteries. Access to the batteries is obtained by loosening the four captive screws and removing the electronics cover as
shown
in Figure 24.
CAUTION
Always use lithium batteries. Alkaline batteries
produce
magnetic fields that will affect performance of the
locator
particularly when set to the H or XH sensitivity range.
The locator is shipped with a spare set of lithium batteries conveniently stored in the carrying case. It is recommended that when you
use the spare batteries, replace them as soon as possible so that you will never be without batteries in the field.
Schonstedt Instrument Company
14

COVER
BATTERIES
CAPTIVE SCREWS
Figure 24. Exploded View of the Electronic Unit Cover
Troubleshooting Guide
Symptom Possible Cause How to Check How to Fix
No response Dead batteries Replace
-
Batteries not
making contact
Check for
contact
corrosion
Clean
contacts
Battery leakage
Do not
remove
batteries*
Return unit
to
factory
Loose connector(s) Visually inspect Reconnect
Intermittent
Batteries not
making
good contact
Check
for
corrosion
Clean
contacts
Loose connector(s) Visually inspect Reconnect
Uncontrollable
screaming
Weak batteries Replace
-
*Most battery manufactures’ warranties cover the cost of repair or replacement of any device damaged by their batteries. Removing batteries that leak will void
their
warranty.
Schonstedt Instrument Company
15

Schonstedt Instrument Company
16

SERVICE INFORMATION
If your locator needs service, please return it to the factory along with the following information: Name, Address, Telephone, Fax
number, Where Purchased, Date, and Description of Trouble(s). An estimate will be provided prior to service work being done.
See
shipping information on page 19.
SPECIFICATIONS
(Specifications subject to change without notice)
Input Power:
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Supplied by two lithium 9-V batteries
Battery Life:
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60 Hours (intermittent usage)
Output:
Audio
Output Option. . . . . . . . . . . . . . . . . . . . . . . Signal increases or decreases in volume
Switch at “A” . . . . . . . . . . . . . . . . . . . . . . . with gradient-field intensity
Output Option. . . . . . . . . . . . . . . . . . . . . . . Signal increases or decreases in frequency
Switch at “
B
” . . . . . . . . . . . . . . . . . . . . . . . with gradient-field intensity
Visual
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Digital readout expanding bar graphs
Indicate polarity (positive or negative)
and
Relative strength of the magnetic field
Battery Check:
. . . . . . . . . . . . . . . . . . . . . . . . . . . . BATT 4-segment LCD
Weight:
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Approximately 2.5 lbs. (1.14 kg)
Operating Temperature:
. . . . . . . . . . . . . . . . . . . . -13° to 140°F (-25° to 60°C)
Overall Length:
. . . . . . . . . . . . . . . . . . . . . . . . . . . 34.5 in. (87.6cm)
Waterproof Length:
. . . . . . . . . . . . . . . . . . . . . . . . 21 in. (53.3cm)
Nominal Sensor Spacing:
. . . . . . . . . . . . . . . . . . . . 14 in. (35.6cm)
Construction:
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . Rugged, all solid state
Schonstedt Instrument Company
17

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 3 years (with the return of the Custo
mer
Registration Card) after the shipment by Schonstedt to the original purchaser.
Schonstedt’s obligation under the warranty is limited to servicing or adjusting any product returned to the factory for this purpose
and to replacing any defective part thereof. Such product must be returned by the original purchaser, transportation charges p
repaid,
with proof in writing, to our satisfaction, of the defect. If the fault has been caused by misuse or abnormal conditions of op
eration,
repairs will be billed at cost. Prior to repair, in this instance, a cost estimate will be submitted. Service or shipping information
will
be furnished
upon notification of the difficulty encountered. Model and serial numbers must be supplied by user. Batteries are specif
-
ically excluded under the warranty.
Schonstedt shall not be liable for any injury to persons or property or for any other special or consequential damages sustained or
expenses incurred by reason of the use of any Schonstedt product.
FOR SERVICE OR REPAIR
Please ship locator (in its case) to:
Schonstedt Instrument Company
4 Edmond Road
Kearneysville, WV 25430
Attn: Customer Service Dept.
PATENTS
Manufactured under one or more of the following Patents: United States: 4,163,877; 4,258,320; 4,803,773; 4,839,624;
5,097,211; 5,136,245; 5,138,761; 5,239,290. Other United States and foreign patents pending.
Schonstedt Instrument Company
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