Lornet LORNET-24 User manual

NON-LINEAR JUNCTION
DETECTOR
L O R N E T - 24
USER MANUAL
2015

U
US SE ER R M MA AN NU UA AL L
1. Introduction
The non-linear junction detector “LORNET-24” (further NLJD) is used for search and
location of electronic devices both in active and switch-off state.
The detector operation is based on the property of semiconductor components to
generate a response at the 2d and 3d harmonics when radiated by an RF probing
signal. Semiconductor components of artificial origin will have a higher level second
harmonic while semiconductor components of natural origin (e.g. oxide films) will
have a higher level third harmonic respectively. An NLJD analyzes the 2d and 3d
harmonics response of the radiated objects, which enables a quick and reliable iden-
tification of electronic devices and natural oxide semiconductors.
The NLJD “LORNET-24” automatically finds the best receiving frequency channel
free of noise and distortion providing flawless operation even in the complicated
electromagnetic environment. The frequency tuning algorithm implemented in
“LORNET-24” automatically selects the RF probing signal frequency such that the
noise level in 2d harmonic receiving channel is held minimal, while digital processing
of a demodulated signal gives maximum sensitivity.
There are two types of radiated signals:
-continuous wave carrier (CW);
-pulse modulated carrier with duty cycle 40 (pulse).
This enables to combine wide detection range and reliable identification of the de-
vices found.
Output power automatic control mode significantly simplifies operator’s work. “LOR-
NET-24” simultaneously displays the 2d and 3d harmonics levels at its LED panel.
Besides, the 2d and 3d harmonics levels can be estimated in turn aurally by click
repetition rate reproduced through a built-in loudspeaker or wireless earphones.
The detector of the curved over-radiated UHF-signal enables to detect operating e-
devices containing acoustic transformer in the CW mode of carrier frequency aurally.
2. Specifications:
Types of the radiated signal:
-continuous wave carrier;
-pulse modulated carrier with a duty cycle 40.
Carrier frequency step is 0.2MHz within 2409.6 … 2410.4 tuning range. Frequency
selection is automatic. Radiation at a carrier frequency with a minimum noise level in
the 2d harmonic receiver path is possible.
Maximum radiated power in the CW mode does not exceed 0.5W.
Peak radiated power in the pulse mode does not exceed 10W.
The radiated power level is controlled automatically or manually using a built-in at-
tenuator. Dynamic control range is 30dB down from the maximum output power value
with 11 level gradations.
Real sensitivity of receivers is not worse than –140dBW provided signal to noise ra-
tio is 10dB.
Tuning frequencies of receivers are equal to double and triple frequencies of a
transmitter.
Dynamic range of the receiving path is more than 70dB.
Time of continuous operation with a lithium-Ion battery at the maximum radiated
power is not less than:
-3 hours in the pulse mode;
-1,5 hours in the CW mode.
Operation time from 220V mains at a power adapter connected is unlimited.

Weight of the device equipped does not exceed 0.65kg.
Operating conditions:
-ambient temperature 5…40C.
-pressure 450mm of mercury
3. Delivery set, design and accessories
3.1. The device includes units and accessories stated in the Table below:
No.
Description
Q-ty
1.
2.
3.
4.
5.
Receiving-transmitting antenna assembly and control panel
Power adapter
Wireless phones including:
receiving device and earphones
User manual, certificate
Package
1
1
1
1
1
Appearance of the device is shown in Fig. 1, where:
1-LED indicator;
2-receiving-transmitting antenna unit combined with an
indicator;
3-control panel with a power section and a battery (fixed
underneath).
Wireless earphones, chargers and additional batteries are
not shown in the figure.
4. Purpose of the Detector Basic Units
4.1. The receiving-transmitting antenna unit with built-in LED
indicators (shown in Fig. 2) is used for:
Analysis of distortion and interference in the instrument
receiving path, which is made each time the detector
transmitter is switched on. Therefore, if an interfering sig-
nal appears during operation (in a complicated electro-
magnetic environment) it is necessary to turn the detector
transmitter off and on from time to time thus selecting an
optimal frequency automatically, providing the best sensi-
tivity and detection range of semiconductor components.
Generation of CW or pulsed RF signal.
Reception and digital processing of the 2nd and the 3rd frequency harmonics. Simul-
taneous display of the 2nd and the 3rd harmonics levels gives the opportunity to dis-
tinguish with a high reliability between sig-
nals of artificial semiconductors integrated
in electronic devices and natural corrosive
ones which appear at oxidation of connect-
ing points of various metals.
Demodulation of the 2nd and 3rd harmonics
response, their amplification to the level re-
quired for tapping both to earphones and a
built-in loudspeaker. The amplification is
adjustable within 20 dB. The operator can
listen to demodulated signals of the 2nd and
3rd harmonics in turn.
Fig. 2
1
2
3
Fig. 1

Fig.3
1
2
Fig. 5
1
Fig. 4
7
9
8
1
6
2
10
3
4
5
Indication of the probing signal levels (1) as well as of the 2nd (2) and 3rd (3) harmon-
ics levels (Fig. 2).
4.2. Hinge joint of the receiving-
transmitting antenna unit with a knob is de-
signed to transform the unit into transporta-
tion position. (see Fig.3). Besides, it helps
the operator to fix antenna in a position
convenient for search. Fig. 3: 1- Fixing
device; 2- Hinge joint.
4.3. The control panel is used to control
operation of the detector. It consists of a
case combined with a battery and fixed on
the arm. Control board, buttons for opera-
tion modes control and display LEDs are
placed in the package. Control buttons are divided into two groups by their function:
«AUDIO» placed in the upper half of the panel and «POWER RF» in the lower half.
Control panel is shown in Fig.4
The following buttons are referred to «AUDIO»
group:
1-LEDs and LSTN button for switching of acoustic
indication to the output of the 2nd or 3rd harmonics.
2- LEDs and OUT button for switching acoustic out-
put to earphones or a built-in loudspeaker.
3- LEDs and RF button for switching between types
of the radiated signal (CW –continuous, PULSE –
pulsed).
The following buttons are referred to «POWER RF»
group:
4- LEDs and PWR button for switch on/off the prob-
ing signal transmitter. On the switch on the automatic
mode of output power control (AUTO) is set by de-
fault. To switch over to a manual mode of output
power control (MNL) press one of the LEVEL buttons when a transmitter is turned on.
To return to the automatic mode turn the transmitter off and then turn it on.
5,6 - LED and a button for receiving unit attenuator control.
7,8 - LEVEL buttons for control of radiat-
ed signal power in MNL and AUTO
modes (- high, - low). It is possible to
set maximum power level by pressing
LEVEL button (- high, - low) in AUTO
mode before the probing signal transmit-
ter is turned on.
9,10 - Volume buttons for volume control
(- high, - low). Functions of control
panel indicators: continuous light of any
indicator corresponds to “on” position,
absence of light –to “off” position. Simul-
taneous flickering of all indicators on the
panel shows that the battery is dis
charged and needs to be replaced.

Fig. 7
4.4. On the side surface of the control panel (see 1 in Fig. 5) a slide-type power
switch is placed. A slide position corresponding to «ON» is marked by a contrast
point. Each time before operating the device it is recommended to make the full
charging of the battery.
4.5. Battery charging is to be made with a power adapter and a battery charger sup-
plied with the instrument only. Using other chargers is not allowed.
For charging it is necessary to connect a low-voltage connector of the power adapter to
the socket placed underneath the front side of the control panel. (see 1 in Fig.6).
A red LED (see 2 in Fig.6) is lightning while charging (see 2 in Fig.6). When a battery is
completely charged, a red LED goes out, and a green LED lights up (see 3 in Fig.6).
Charging time of a fully discharged battery does
not exceed 5 hours (typical value is 3.5 h). In case
of a failure (charging is not complete within five
hours) a charger switches off automatically, both
LEDs will go out.
4.6. Wireless telephones consist of a receiving de-
vice and earphones. Appearance of the receiving
device and position of control units are shown in
Fig.7
Receiving device operation order:
Using a power adapter supplied with the instrument make sure with a help of the
charge indicator that the battery is completely charged.
Using of other power adapters is forbidden.
Connect head phones to a corresponding socket of a receiving device.
Turn the receiving device on by a slide-type switch (control by the turn-on indica-
tor).
Using volume control set comfortable volume level.
Socket for phones
connection
Socket for power adapter
адаптера
Charge indicator (lights
during charging)
“ON” indicator (lights at
turn-on)
Volume control
Slide-type switch
Fig. 7

If the receiving device is turned on when the detector is off, then there is only a
noise signal in the head phones at higher volume. After turning on acoustic indicator
signals corresponding to operating mode of the detector appear in the earphones.
5. Safety Measures
5.1. By requirements of electric safety the detector corresponds to protection class 1
(according to the Russian standard).
5.2. The instrument is to be operated only by persons who have been duly instructed
for safety measures while working with electric and measuring devices with open RF
energy radiators.
6. Operation Order.
6.1. Remove the detector from the package, and the battery from a protective case,
connect the battery to the detector. After device transportation at negative temperatures
it is necessary to keep the device in the switch-off state at room temperature at least 30
minutes.
6.2. To start operation set the battery and turn «LORNET-24» on by the power switch
placed on the control panel (Fig.5). The 2nd and 3rd indicators on the control panel will
light up, indicating that the detector has been powered on.
One yellow LED should be lightning on the antenna unit (a circle scale of the probing
signal power indicator). Its initial position corresponds to the maximum power of the
probing signal. The probing signal transmitter is off (it is turned on after pressing PWR
button only).
The 2nd and 3rd harmonics indicators should not light (flashing of the first LEDs of the 2nd
and 3rd scales is permitted).
Turn the probing signal transmitter on pressing PWR button. This will switch on the
transmitter pulse mode and automatic mode of signal power control. The power of a ra-
diated signal will change depending on a signal level at the 2nd harmonic receiver input.
In the given mode sound information of the 2nd harmonic response is applied to the
loadspeaker or head phones. When switching on mode 3-RD by pressing LSTN on the
control unit, output power of the transmitter is adjusted automatically depending on a
signal level at the 3rd harmonic receiver input. Sound information of the 3rd harmonic re-
sponse is put to the loudspeaker or head phones.
To switch over to the manual mode of the probing signal power control (MNL indicator
lights up) press one of LEVEL buttons after the probing signal transmitter has been
turned on. Turn the probing signal transmitter off and then turn it on for a reverse switch
over.
If it is necessary to tap the third harmonic response turn on mode 3–RD using LSTN
button on the control panel.
During operation in premises with a lot of electronic devices, you will normally have to
decrease the level of the probing signal by 2-4 points counterclockwise from the initial
position.
The optimum level of the probing signal is reached experimentally.
6.3. Simultaneous flashing of all indicators on the control panel indicates that the battery
is discharged and needs to be replaced urgently. In this case the power should be
turned off and the battery - replaced.
6.4. If a response signal is to be tapped by phones, switch over acoustic indication to
the head phones mode pressing the corresponding button on the control panel (see 2 in
Fig.4) and turning wireless phones on (according to their User Manual).
Attention:

1). Do not direct the antenna towards the operator and people nearby.
2). While operating the device constantly monitor batteries state replacing them in-time
(by the indicators signal). The batteries must be kept fully charged.
3). Charging should be done in a charger supplied with the instrument only.
4). Self –assembling or - disassembling and use of undue chargers is forbidden.
5). When the operation is finished, or during long operation breaks, it is recommended
to remove the battery from the detector.
6). To avoid short-circuiting of leads (see 1 in Fig.6) batteries are to be kept in an isolat-
ed case when not used.
7). If necessary under complicated interference conditions as well as for more preci-
sious localization and protection of radio-receiving devices from overloading attenuators
can be used by switching them on consequently using “ATT” button. Weakening of each
attenuator is 2 dB. Number of attenuators - 5.
7. Search Recommendation
7.1. If possible remove electronic devices from the room examined. If it is impossible,
examination should be done at a decreased radiated power.
7.2. Set maximum radiated power level and one of the operation modes of the receiver.
7.3. In the CW mode it is recommended to use manual operation mode “Man” only.
7.4. Place the antenna unit parallel to the surface examined at the distance not exceed-
ing 10cm.
7.5. Slowly moving the antenna unit parallel to the surface examined and changing ori-
entation of antennas, analyze changes in the signal received at the 2nd and 3rd harmon-
ics visually by the indicator (aurally the click repetition rate should be maximum).
7.6. Analysis of the received 2nd and 3rd harmonics levels is made by number of LEDs
lightning on the corresponding indicator scale.
7.7. Remove the antenna unit from the surface examined or decrease output power and
repeat measurements stated in 7.4. of the present manual. For a more accurate loca-
tion as well as for protection of receiving devices from overload it is possible to de-
crease the signal level using attenuators.
7.8. When an artificial р-n transition is found you will normally see stable lightning of the
2nd harmonic indicator LEDs. While rapping at the suspected place of a p-n transition,
readings of LEDs do not change.
7.9. When a natural р-n transition is found, you will observe stable lightning of the 3rd
harmonic indicator LEDs. While rapping at the examined surface intensively, readings
of indicators by the 3rd harmonic will change, as a rule.
The search technique offered does not reflect all nuances which may appear in each
exact case, and represents a recommendation only.

C
CE ER RT TI IF FI IC CA AT TE E
1. General
1.1. Before operation thoroughly study User Manual for «LORNET-24».
1.2. The warranty certificate is included in the delivery set and should be always kept with the
instrument.
1.3. If the device is sent for repair or to a different place during operation the Certificate
is to be shipped with the instrument.
2. Delivery set
Name
Q-ty
Serial No
Notes
A receiving-transmitting antenna unit
with a control panel and a built-in bat-
tery with a charger
1
Power adapter
1
Wireless phones
included: a receiver and earphones
1
User manual
1
Certificate
1
Package
1
3. Warranty
3.1. Warranty period for «LORNET-24» is 12 months upon supply to the customer.
3.2. Life time is 6 years.
3.3. If the device fails during warranty period provided the customer has followed all the
operation, transportation and storage rules, the manufacturer is to make the repair free
of charge or replace the device.
3.4. Warranty does not cover power elements.

4. Claims Data
In case of package damage during transportation claims are applied to the transporta-
tion organization in the order stated.
If delivery set is not complete or the NLJD is damaged, provided a package is not dam-
aged, an Act is made together with a representative of the manufacturer.
If a defect appears during warranty period, a customer is to send the NLJD to manufac-
turer with an accompanying letter, stating the reason of the claim.
All claims with a brief description of encountered problems and measures taken are
recorded in Table 1.
Table 1
Claim content
Reason, measures taken
Notes