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GT-4000 Gold Tester
Instructions
The GT-4000 Gold Testers is a portable electronic device for efficient and
quick determination of gold karat value (from 6 to 24 karat), and pure platinum.
The GT-4000 Gold Tester also distinguishes solid gold from gold-plated items.
The GT-4000 will develop a residual charge during storage.
Upon first use always ignore first test
result. Only second test will provide accurate result. As long as unit is
activated subsequent first tests will be accurate.
OPERATION PROCEDURES
The GT-4000 test set consists of a display unit
(which operates on two 9-volt alkaline batteries), sensor with rotary
cap containing a gel cartridge, a test plate, and a tri-cable for
connecting the unit to the sensor and test plate.
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Inserting the Testing Gel
Remove the stationary/rotary cap from sensor nozzle by turning the lower
light-colored barrel on the top of the sensor counter clockwise. Do
not try to remove by turning the top
dark-colored rotary cap, as this will damage the cap assembly.
Remove the polyethylene cap on the gel cartridge and fully insert
the rectangular feed-screw end into the appropriate slot of the rotary cap.
Reassemble the cap assembled and cartridge into the sensor body.
Turn the light-colored barrel clockwise until fully seated.
Turn the dark-colored barrel counter clockwise until the first drop of gel
appears at the sensor nozzle.
Set-up & Testing-
The following step-by-step procedure must be followed to properly perform gold
tests
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- Connect the black wire to the sensor plug outlet, the black and red
wire connector to the display unit, and red
wire to the testing plate.
- Turn the unit "ON" by means of the slide switch on the right side of
the electronics unit. The unit will automatically be set to low karatage.
It is always necessary to test gold in the low karatage mode initially
before testing in the high karatage mode. Even if the gold is known to be
of high karatage you must pre-test the alloy in the low mode and switch to
high mode after testing in the low karatage mode to obtain satisfactory
results. After testing in low karat mode, if High Karatage Testing is then
desired, press the "HI/LOW KARAT" switch to illuminate the "HI KARAT ON"
light and refer to the Hi Karatage Testing section. When the "High
Karatage On" light is illuminated, you can only test high karatage (18
karat or greater) gold. You will need to use this mode when measuring
18-24 karat gold. The first test in the high karat mode is a pre-test and
may give erroneous results—Always
test high karatage gold a second time to determine karatage.
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3. Select and clean with eraser a testing point on the object; obtain one
drop of gel by turning the sensor rotary cap (dark colored barrel)
counter-clockwise until gel is dispersed from sensor end. Firmly press the
sensor nozzle to the pre-selected and cleaned testing point and press the "TEST"
button.
NOTE: use only a
small amount of gel to test. Lightly wipe off excess gel on tissue or towel
before test so that only small dome of gel is present on tip of sensor.
Excessive use of gel will provide erroneous low karatage readings. It only
necessary to apply a small amount of the gel between the gold being tested and
the sensor.
After the test, there should be a small round wet spot on the
tested gold sample. This verifies a good contact between the sensor tip and the
sample.
4) Maintain sensor in the same vertical position for
approximately 4-5 seconds while the instrument indicates the numbers on the
LCD display. The first test after turning the unit "ON" may give an inaccurate
result due to residual charge and should be ignored. Repeat the operation
numbers 7 and 8. Then refer to the Karat Table to convert the displayed number
into karat value.
Please Note:
1) Dispense a drop of the
gel and then remove it before each test to eliminate residual charge in sensor.
2) Do not allow gel to touch alligator clip during test.
3) Some flat herringbone gold chains require a special
cleaning technique due to special factory applied coating on the chain. To clean
this coating, put a small drop of nitric acid on the test spot and then dry with
a paper towel or vigorously clean with eraser. Be sure that the alligator clip
and sensor nozzle are making good electrical contact with test object.
5) The Gold Tester is able to distinguish between gold-plated
and gold-filled items when the plating layer is less than one micron.
6) The gel may be stored at room temperature for an extended
period (more than one year) (26.6�C). For unlimited storage life, the
manufacturer recommends storing gel in a standard refrigerator (do
not freeze).
7) Do not try to open or disassemble the display unit because
it will damage the electronic parts and void the manufacturer's warranty.
9) Do not use excessive
gel for testing.
10) If tested gold piece is displayed as "Not Gold", check
all connections of wires in unit, plate, and sensor. Check to insure that the
proper amount of gel has been dispensed and that it forms a nice little round
spot on the item being tested.
11) FIRST READING - The machine is not infallible 'end from
time to time, for a variety of reasons, you may get a reading, high or low,
which is inconsistent with your understanding of the expected karatage.
ALWAYS
make additional readings in other locations on the jewelry with special
attention to cleaning and gel dispersal to verify unusual readings.
12) FINE FINE GOLD - Very fine (thin) chains are very
susceptible to crushing by the dispenser. Always avoid pressing the dispenser
against the chain when testing fine gold chains while assuring gel contact. Two
of three tests are recommended.
13) AIR GAP- Occasionally an air bubble will make its way to
the tip of the dispenser causing a low or not gold reading. Retest when the
result is suspect.
14) CLEAN TIP- If the tester has not been used recently, then
clean the tip with the plastic cleaner provided by inserting the tip into the
nozzle end of the sensor to remove any dried or used gel in the sensor tip.
Accumulated dried gel will clog the sensor tip and cause the gel to bypass the
plunger in the gel cartridge. If gel drops are not dispensed by rotating the
twist cap immediately, clean the sensor using 1171 Electronics SC-10 Cleaner
Accessory Kit. To avoid clogging it is good practice to clean the sensor each
time the gel cartridge is replaced using the SC-10 Cleaner Kit.
14) SOLDER/HEAVY CASTINGS - Solder joints and certain spots
on heavy castings may give erroneous readings due to the solder composition or
non-homogeneous gold. Retest a new area if your result is suspect.
15) ITALIAN GOLD - Many Italian gold chains and necklaces are
coated with a wax like material. If the readings are suspect, clean the area to
be tested by heavy erasing or with a drop of nitric acid. If the karat value
increases with heavy erasure, you may be sure the gold is coated. In all cases,
nitric acid will remove the coating.
16) SKIN OILS – In heavily worn/used pieces, clean the
testing item thoroughly with the eraser or non-acetone nail polish remover.
17) PLATED GOLD - Often a pin prick or small scratch on
suspected plated pieces is sufficient to allow the gel to penetrate to the base
material.
Warrantee:
The GT-4000 is warranted to be is free from defects in
material and workmanship for a period of two (2) years from the date of
purchase. This warrantee does not include damage caused by abuse or misuse and
in no event shall we be liable for any incidental or consequential damages due
to any cause whatsoever.
This warranty does not cover any product where an attempt has been made
to disassemble the unit.