ST CAYMAN 401 User manual

PORTABLE
NONLINEAR JUNCTION DETECTOR
ST 401 ‘CAYMAN’
OPERATING MANUAL
English

OPERATING MANUAL
22
CONTENTS
pg.
1. Description
23
1.1. Purpose
23
1.2. Delivery Package
23
1.3. Technical Specifications
24
1.4. Principles of Operation
25
1.5. Operation Modes
25
1.6. Structure
26
1.6.1. Antenna Module
26
1.6.2. Main Unit
28
2. Use
29
2.1. Preparation
29
2.2. Adaptive Mode
30
2.3. Operational check with test dummies
30
2.4. Manual Gain Control
31
2.5. Listening (Audio Mode)
33
3. Power Supply
35
4. Operating Restrictions
36
5. Storage and Transportation
36
6. Warranty
36

ST 401 ‘CAYMAN’ NLJD
23
This operating manual contains important technical information and guidance on proper use
of the product. Please read the manual before using ST 400 Cayman.
1. Description
1.1. Purpose
ST 401 CAYMAN is intended to detect and locate
•eavesdropping electronics
•mobile phones and SIM cards
•any other devices utilising semiconductor technology
ST 401 allows detecting electronic devices, whether active or not, as well as finding
their exact location. It also enables one to distinguish between return signals from real
semiconductors and other kinds of responses, such as those given by corrosion or metal-oxide-
metal structures.
1.2. Delivery package
Item
Quantity
No. in Fig.1
ST 401 ‘Cayman’ NLJD
1
1
Accumulator Battery (type 18650)
4
2
Electric Charger
1
3
Charger Power Adapter
1
4
Headphones
1
5
Semiconductor Imitating Dummy (marked red)
1
6
MOM-Structure Imitating Dummy (marked blue)
1
7
Shockproof Case
1
Operating Manual
1
not shown in figure
Fig. 1

OPERATING MANUAL
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1.3. Technical Specifications
Range of radiated frequencies
2–3GHz
Max. peak radiated power
< 2W
Antenna polarisation
elliptic
Operation modes
SEARCH, AUDIO, ADAPT
Sensitivity range in manual mode
40dB (5 values with 8dB increment)
Visual indication
three 16-segment gauges
Aural indication
internal speaker or headphones
Power supply
two 3.7V Li-ion batteries (type 18650)
Time of operation on one battery charge
3–4 hours, depending on operation mode
Battery charging time
< 3 hrs
Operating conditions
–working temperature range
+5...+40°С
–relative air humidity
up to 85 percent (at 25°С)
Weight (with batteries)
0,85kg
Dimensions (length×width×height) folded
220х130х100mm
Weight of full set in case
5,1kg

ST 401 ‘CAYMAN’ NLJD
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1.4. Principles of Operation
ST 401 ‘Cayman’ is a nonlinear junction detector, or NLJD. Instruments of this type employ
active detection, i.e. they emit probing signals and analyse the return. Their primary search targets
are electronic devices, and those typically consist of circuit plates with conductive elements and
various semiconductor parts connected to them, such as diodes, transistors, and microchips.
The probing electromagnetic radiation induces variable electromotive forces in these loops, and
electronic components with a non-linear current-voltage curve transform the initial signal into its
higher frequency harmonics, which come back to the NLJD’s receiver.
Higher harmonics can also be re-radiated by corroded metal or the so-called MOM-diodes,
metal-oxide-metal structures brought about by contacting metal surfaces. However, these
formations return somewhat different spectra than semiconductors.
With ST 401 one can distinguish with high probability between responses given by real
semiconductors, and those ‘faked’ by MOM-structures or corrosion.Another important advantage
is a confident detection of search targets behind partially shielding obstacles, which is achieved
by simultaneously radiating several frequencies within the 2-3GHz band and analysing the
composite picture of the reflection spectrum.
1.5. Operation Modes
The NLJD ST 401 ‘Cayman’ has the following modes of operation:
Primary operation mode: SEARCH
Secondary operation mode: AUDIO
Service mode: ADAPT
The main operation mode named SEARCH is meant for detecting nonlinear targets and
identifying them, based on the response levels as indicated by 16-segment bars.
The auxiliary operation mode named AUDIO allows demodulating the response and listening
to it through the built-in speaker or headphones. Use this mode upon detecting a response in the
SEARCH mode.
The service mode namedADAPT isused tooptimisethe parameters ina givenelectromagnetic
environment and thus maximise the effectiveness of search. Engaging this mode is necessary
every time the device is switched on. It is advisable to pause during searches from time to time,
to repeat this procedure. During adaptation, the antenna must be pointed away from electronics
and large metal objects.

OPERATING MANUAL
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1.6. Structure
Structurally, the ST 401 ‘Cayman’ NLJD consists of the antenna module and the main unit
connected by way of a hinge joint. The general appearance of ST401 is shown in Fig. 2, the
numbers standing for:
1 –antenna module
2 –main unit
Fig. 2
1.6.1. Antenna module
The antenna module comprises a receiver-transmitter unit, a control-display unit, and an
aerial, all of which are assembled on a single platform and incorporated in a single body.
Fig. 3
The antenna module is connected with the handle through a hinge joint that allows adjusting
the incline within the vertical plane, as shown in Fig. 3. Loosen the hinge screw (2, Fig. 6) to
change the incline, then tighten the screw again.

ST 401 ‘CAYMAN’ NLJD
27
Fig. 4
On the surface of antenna facing operator, there are an indicator panel, a socket for the power-
and-control cable, and a USB port for computer connection (Fig. 4). The numbers in Fig. 4
stand for the following:
No in
Fig. 4
Description
Colour
Subscript on
indicator panel
1
16-segment led gauge of threat-type response
levels
red
1
2
16-segment led gauge of MOM-type
response levels
blue
2
3
16-segment led gauge of reflection levels
white
3
4
Power-on led indicator
red
POWER
5
SEARCH mode indicator
yellow
SEARCH
6
AUDIO mode indicator
yellow
AUDIO
7
5-segment tuning bar*
yellow
TUNING
8
socket for power-and-control cable
CONTROL
9
USB port
USB
* the TUNING segment bar has two functions:
–in the SEARCH mode, it shows the selected sensitivity of the receiver (SEN)
–in the AUDIO mode, it shows the selected frequency combination (CH 1..5)
The boresight directions of the receiving and transmitting antennas are shown in Fig. 5.

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1.6.2. Main Unit
The main unit of ST 401 ‘Cayman’ consists of a battery compartment, a control panel, and
mechanical parts that form the bearing structure. The appearance of the main unit and the location
of its components are shown in Fig. 6.
Fig. 6
The numbers in Fig. 6 stand for:
1 –bracket mount for the antenna module
2 –lever handle of the clamp
3 –power-and-control cable with plug
4 –headphone socket
5 –power and volume knob
6 –battery compartment
7–control panel
8–grid of the built-in speaker
9 –ID plate
10 –battery compartment cap
Fig. 5

ST 401 ‘CAYMAN’ NLJD
29
A three-button control panel is located in
the upper part (Fig. 7).
The MODE button (1, Fig. 7) is used
to set the operation mode of the device. A
short press of this button alternates between
SEARCH and AUDIO; holding it down for a
few seconds will set the device to the ADAPT
mode.
The other two buttons marked with arrows
and (2 and 3, Fig. 7) are for tuning
the device. Depending on the mode, they
allow:
–in the SEARCH mode, increasing
and decreasing the receiver sensitivity,
respectively.
–in the AUDIO mode, setting the desired
frequency combination.
Fig. 7
The main unit has a battery compartment for 2 type 18650 accumulator batteries. Those are
enclosed with a screw cap (10, Fig. 6) that also serves as the negative contact.
Fore of the handle are the headphone socket (4, Fig. 6) and the power and volume knob
(5, Fig. 6). In the lower part there are a speaker grid (8, Fig. 6) and an ID plate (9, Fig. 6) that
indicates:
–product name
–serial number
–logo, and name of the manufacturer company.
2. USE
2.1. Preparation
Take the device and 2 batteries out of the case. Examine the antenna module, handle, cable,
and socket for mechanical damage. Examine the batteries for mechanical damage and electrode
corrosion. Do not use the device if any such defects are found! To replace the batteries, do the
following:
•unscrew the battery compartment cap;
•insert two accumulator batteries as
shown in Fig. 8, making sure you
observe the polarity;
•screw the cap back in place.
Fig. 8

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Make sure the power switch (5, Fig. 6) is in its leftmost position (OFF). Insert the power-and-
control cord plug (3, Fig. 6) into the socket (8, Fig. 4) on the antenna module.Activate the device
by rotating the knob clockwise. The device status will be displayed on the antenna module as
shown in Table 1 below.
Table 1
Legend
Colour
Light indication
Interpretation
POWER
red
continuous
The antenna module is powered
properly.
blinking
The battery is discharged and needs
to be replaced.
TUNING
SEN
yellow
continuous
This displays receiver gain. At
startup the gain is automatically set
to maximum, which is signalled by
all the 5 indicator segments being lit.
SEARCH
yellow
continuous
This displays the operating mode.
The SEARCH mode is selected
automatically at startup.
Upon activation of the device one or more segments of the signal level gauges (1..3, Fig. 4)
may light and go out spontaneously. This would mean that the device should need to be adjusted
to the electromagnetic environment using the adaptive mode.
2.2. Adaptation mode
Toactivate this mode, press and hold for 3-4 sec the MODE button (1, Fig. 7) on the control
panel. The antenna must be directed away from large metal objects and anything that is presumed
to contain nonlinear elements (it is often best to point the antenna at either the floor or ceiling).
The adaptation takes 10–15 seconds, with all the indicators but TUNING lit in the meantime
on the antenna module. The TUNING indicator will be showing a consecutive lighting of
segments. The user can check if any of the indicator LEDs are dead.
Upon adaptation the device status will be displayed in accordance with Table 1.
Upon activation of the device one or more segments of the signal level gauges (1..3, Fig. 4)
may light and go out spontaneously. This would mean that the device should need to be adjusted
to the electromagnetic environment using the adaptive mode.
2.3. Operational check with test dummies
For that purpose, place the dummy that is marked red in an area free of responses from
nonlinear elements or reflecting surfaces.
Press button (3, Fig. 7) repeatedly to set the receiver gain at 3 lit segments of the
TUNING indicator, which corresponds to medium sensitivity.
Point the antenna at the test dummy and find the distance at which all the 16 segments of the
INPUT LEVEL Gauge bar 1 light up. For a device that is in proper working order and has self-
tuned properly, this distance should be no less than 0.8 m.