3.2.3
Sensitivity
When the power is turned on, sensitivity is set to “A shallow”. “A shallow” is a sensitivity setting that
is applicable to the detection of rebar with a depth of less than 10 cm in general concrete.
"A" of "A shallow" indicates the overall sensitivity; "shallow" indicates depth sensitivity.
There are five levels for overall sensitivity: "-2, -1, A, +1, +2." In general, use the unit in the "A"
setting. Use the +side to increase sensitivity and use the –side to reduce sensitivity.
There are two levels for depth sensitivity: "shallow and deep." Select "shallow" when the object to
be probed is at a depth less than 10 cm. Select "deep" when the object to be probed is at a depth of
10 cm or more.
To change the sensitivity, press 3
GAIN
.
The sensitivity is changed as follows:
A, shallow
→
+1, shallow
→
+2, shallow
→
-2, deep
→
-1, deep
→
A, deep
→
+1, deep
→
→
+2, deep
→
-2, shallow
→
-1, shallow
→
A, shallow
→
+1, shallow
→
Remarks
•
To change sensitivity for scanning results, press 3
GAIN
after scanning.
If sensitivity is changed after scanning, the unit uses the new sensitivity for the next
scanning.
For the changing of sensitivity after scanning, see "Section 3.3.2 Sensitivity Switching."
3.2.4
Antenna Mark
If core-boring or reinforced rebar locations are known beforehand (shown on a
construction diagram) the NJJ-95B can mark the locations by placing an “Antenna Mark”
at the applicable places during scanning.
The method of use for this antenna mark is shown below.
a) Place
the 14
V
on the side of the unit over the start line and the forward/backward 14
V
over the sense test line.
b) Press 9
START
. After about one second, a short single buzzer sound is generated, the
fixed cursor is displayed at a position of about 10cm of the movement distance scale on the
B mode screen, and then scan test preparation is complete.
c) Move the unit on top of the scan test line at a speed of less than 40 cm/s by rotating the
wheels. If speed exceeds 40 cm/s, a buzzer sounds and the data for that timeframe is
invalid. Please perform the scan test again.
d) Push 10
MARK
when the 14
V
on the side of this unit overlaps the rebar position or
core-boring as based on design blueprints. (A
▼
is shown on the movement distance
gauge)
e) Press 9
START
again to finish. A double buzzer sound is generated and the scan test is
‑ 38 ‑
Summary of Contents for Handy Search NJJ-95B
Page 1: ...Handy Search Instruction Manual...
Page 8: ...Appearance of the NJJ 95B vii...
Page 21: ...Rear view Units in trigonometry mm 9...
Page 24: ...8 14 15 Figure 2 2 Side View 16 17 14 18 Figure 2 3 Rear View 12...
Page 73: ...Display of thumbnails Figure 3 17 CF Control Screen 61...
Page 83: ...B Terminals ACharge confirmation mark Figure 3 22 Battery Pack 71...
Page 85: ...Shutter Charge lamp Figure 3 23 Battery Charger 73...
Page 96: ...Concrete Rebar D 75mm L 75mm D 75mm Difficult to implement 84...
Page 103: ...Dimensions Weight About 149 W x 147 H x 216 D mm Approximately 1 1kg 91...
