The document is Pawan Kumar Pandey's training report submitted to Hindustan Aeronautics Limited (HAL) after completing a 4-week training program. It provides an overview of HAL, including its divisions and products. It describes Pawan's work in the Special Test Equipment Group (STEG) department, which designs, fabricates, and maintains special test equipment used for testing electronics components and systems. The report covers concepts like the importance of training, HAL's fighter planes like the Jaguar and Su-30, and avionics divisions involved in manufacturing systems for navigation, displays, and weapons aiming.

1. 1
SUBMITTED IN ACCOMPLISHMENT OF
(FROM 10th
JUNE 2015 TO 9th
JULY 2015)
SUBMITTED BY: SUBMITTED TO:
PAWAN KUMAR PANDEY Mr. RAJESH AGARWAL
B.TECH (ECE, 3rd YEAR
) D.G.M (TRAINING)
G.N.I.O.T, GREATER NOIDA H.A.L. KORWA, AMETHI

2.  ACKNOWLEDGEMENT
 CERTIFICATE
 CONCEPT OF TRAINING
 IMPORTANCE OF TRAINING
 HAL-AN ORGANISATION OVERVIEW
 ABOUT FIGHTER PLANES
 ABOUT HAL KORWA
 INTRODUCTION
 DEPARTMENTS
 S.T.E.G.
 FDR
 INS
 HUDWAC
 PROJECT REPORT
 PCB DESIGNING
 SOLDERING
 DO ’S & DONT ’S

3. This is to certify that the project report entitled “SPECIAL TEST EQUIPMENT
GROUP (STEG)” is a bonafide work of report developed by PAWAN KUMAR
PANDEY (Vocational Trainee, B.TECH. EC 3RD
YEAR) period from 10TH
June,2015 to 09TH
JULY ,2015. This training report forms a part of partial
fulfillment to B.Tech Degree course.
The produced report is genuine and has not been submitted elsewhere for any
reason whatsoever. I am fully satisfied and appreciate the work done on the
project. I wish good luck for the bright future of the candidate.
Sr.Manager (STEG)
HAL AVIONICS DIVN.
KORWA

4. It gives me immense pleasure to state that I have been given opportunity to
produce training report at HAL Avionics Division Korwa for a period of four
weeks. I have a long list of people to acknowledge and because of their active
efforts & suggestions the project has been completed well within the time schedule
& with the desired quality.
First of all I would like to acknowledge General Manager HAL Korwa for his kind
approval of my training. I would like to thank Mr. Rajesh Agarwal(DGM
Training),Mr. M.K NISHAD (Training Officer), and Mr. Gauri Shankar (Sr. CS,
Training) for my deputation in the prestigious S.T.E.G. Department. Also I would
like to thank Mr. Hemant Saxena (Sr. Manager), for devoting their prestigious
time.
My Special thanks and gratefulness to Mr. HEMANT SAXENA (Sr.
Manager,STEG), Mr. Mahesh Babu(Manager), Mr. R. C. Dwivedi (Dy.
Manager), Mr. A. S. Rathode, Mr. H. C. Pant, Mr. Ashok Kumar &
Pramendra Singh with whom I actually worked and learned the basics of work in
the industry as well as the practical knowledge.
PAWAN KUMAR PANDEY

5. CONCEPT OF TRAINING
Every organization needs to have
well trained and experienced
people to perform the activities
that have to be done. If the
current or potential job occupant
fail to meet this requirement,
training becomes important as it
raises the skill levels and increase
the versatility and adaptability of
the employees. Training becomes
all the important complex jobs.
In a rapidly changing society, employee, training is not only an activity that is
desirable but also an activity that an organization must committing source to, if it is
to maintain a viable and knowledgeable work force.
Training is a process of learning a sequence of behavior; it is an application of
knowledge. It gives people an awareness of the rules and procedure to guide their
behavior. It attempts to improve their performance on the current job or prepare
them for an intended job.

6. IMPORTANCE OF TRAINING
Training is the corner stone of sound management, for it makes employees more
effective and productive. It is actively and intimately connected with all the
personnel and managerial activities. It is
an integral part of the whole
management programmer with all its
activities functionally inter related.
Training is a practical and vital necessity because, a part from the other advantages
mentioned earlier, it enables employees to develop and rise within the organization
and increases their market value, earning power and job security. It enables
management to resolve sources of friction and make then aware of the fact that the
management is not divisible, it helps them to achieve better co-operation with the
company and a greater loyalty to it. Training, on the hand, benefits the
management by high standards of quality and on the other hand heightens to
morale of the employees because it helps in reducing dissatisfaction, complaints,
grievances, and absenteeism and also reduces the rate of turnover.

7. Hindustan Aeronautics Limited (HAL) came into existence on 1st October
1964. The Company was formed by the merger of Hindustan Aircraft Limited with
Aeronautics India Limited and Aircraft Manufacturing Depot, Kanpur.
The Company traces its roots to the pioneering efforts of an industrialist with
extraordinary vision, the late Seth Walchand Hirachand, who set up Hindustan Aircraft
Limited at Bangalore in association with the erstwhile princely State of Mysore in
December 1940. The Government of India became a shareholder in March 1941 and
took over the Management in 1942.
Today, HAL has 19 Production Units and 9 Research and Design Centres in 7
locations in India. The Company has an impressive product track record - 12 types of
aircraft manufactured with in-house R & D and 14 types produced under license. HAL
has manufactured over 3550 aircraft , 3600 engines and overhauled
over 8150 aircraft and 27300 engines.
HAL has been successful in numerous R & D programs developed for both Defence
and Civil Aviation sectors. HAL has made substantial progress in its current projects :
 Dhruv, which is Advanced Light Helicopter (ALH)
 Tejas - Light Combat Aircraft (LCA)
 Intermediate Jet Trainer (IJT)

8.  Various military and civil upgrades.
Dhruv was delivered to the Indian Army, Navy, Air Force and the Coast Guard in
March 2002, in the very first year of its production, a unique achievement.
HAL has played a significant role for India's space programs by participating in the
manufacture of structures for Satellite Launch Vehicles like
 PSLV (Polar Satellite Launch Vehicle)
 GSLV (Geo-synchronous Satellite Launch Vehicle)
 IRS (Indian Remote Satellite)
 INSAT (Indian National Satellite)
HAL has formed the following Joint Ventures (JVs) :
 BAeHAL Software Limited
 Indo-Russian Aviation Limited (IRAL)
 Snecma HAL Aerospace Pvt Ltd
 SAMTEL HAL Display System Limited
 HALBIT Avionics Pvt Ltd
 HAL-Edgewood Technologies Pvt Ltd
 INFOTECH HAL Ltd
Apart from these seven, other major diversification projects are Industrial Marine Gas
Turbine and Airport Services. Several Co-production and Joint Ventures with
international participation are under consideration.
HAL's supplies / services are mainly to Indian Defence Services, Coast Guards and
Border Security Forces. Transport Aircraft and Helicopters have also been supplied to
Airlines as well as State Governments of India. The Company has also achieved a
foothold in export in more than 30 countries, having demonstrated its quality and price
competitiveness.
HAL has won several International & National Awards for achievements in R&D,
Technology, Managerial Performance, Exports, Energy Conservation, Quality and
Fulfillment of Social Responsibilities.
 HAL was awarded the “INTERNATIONAL GOLD MEDAL AWARD” for
Corporate Achievement in Quality and Efficiency at the International Summit
(Global Rating Leaders 2003), London, UK by M/s Global Rating, UK in
conjunction with the International Information and Marketing Centre (IIMC).

9.  HAL was presented the International - “ARCH OF EUROPE” Award in Gold
Category in recognition for its commitment to Quality, Leadership, Technology
and Innovation.
 At the National level, HAL won the "GOLD TROPHY" for excellence in Public
Sector Management, instituted by the Standing Conference of Public Enterprises
(SCOPE).

10. DIVISIONS OF HAL

11. ABOUT FIGHTER PLANES:
The SEPECAT Jaguar is an Anglo-French jet
ground attack aircraft still in service with
several export customers, notably the Indian
Air Force and the Royal Air Force of Oman.
It was among the first major Anglo-French
military aircraft programs. The aircraft served
as one of the French Air Force's main
strike/attack aircraft until 1 July 2005 (when it was replaced by Dassault Rafale) and with
the Royal Air Force until the end of April 2007.
HAL commenced production of Jaguar International - deep penetration strike and
battlefield tactical Support Aircraft in 1979 under licence from British Aerospace,
including the engine, accessories and avionics.
Jaguar aircraft is designed with 7 hard points (4 under wing, 2 over wing and 1 under
fuselage) capable of carrying a huge load of several of weapons in different combinations
to meet the Customers needs.
Basic Data
Dimensions Wing Data Weight Fuel
Capacity
Power Plant
Length:
16.955 m
Wing Span:
8.691 m
Height:
4.813 m
Area:
24.03 m2
Sweep:
40o
2'
Aspect Ratio:
3.12
Maximum
Take Off:
15700 kg
Pay Load:
4000 kg
Internal :
4.171 liters
With ext.
tanks (max
usable
capacity):
7726 liters
Rolls Royce
Adour MK 811
Turbofan
Max. thrust at sea
level:
Dry - 2549 kg
Reheat - 3810 kg

12. The Sukhoi Su-30 MKI (NATO reporting name: Flanker-H) is a variant of the Sukhoi
Su-30 jointly-developed by Russia's Sukhoi Corporation and India's Hindustan Aeronautics
Limited (HAL) for the Indian Air
Force (IAF). It is a heavy class, long-
range air superiority fighter which ca n
also act as a multirole, strike
fighter aircraft.
The development of the variant started
after India signed a deal with Russia in
2000 to manufacture 140 Su-30 fighter
jets. The first Russian-made Su-
30MKI variant was integrated into the
IAF in 2002, while the first indigenous Su-
30MKI (with Russian engine) entered
service with the IAF in 2004. In 2007, the IAF ordered 40 additional MKIs. As of October
2009, the IAF had 105 MKIs under active service with plans to have an operational fleet of
280 MKIs by 2015. The Su-30MKI is expected to form the backbone of the Indian Air
Force's fighter fleet to 2020 and beyond.
The aircraft is tailor-made for Indian specifications and integrates Indian systems and
avionics as well asFrench and Israeli subsystems. It has abilities similar to the Sukhoi Su-
35 with which it shares many features and components

13. The Dassault Mirage 2000 is a French multirole, single-engine fourth-generation jet fighter
manufactured by Dassault Aviation. It was designed as a lightweight fighter based on the Mirage
III in the late 1970s for the French Air Force.The Mirage 2000 evolved into a successful multirole
aircraft with several variants developed.
The variants include the Mirage 2000N and
2000D strike variants, the improved Mirage 2000-
5 and several export variants. Over 600 aircraft
were built and it is in service in nine countries as
of 2009.
The Mirage 2000 features a low-set thin
delta wing with cambered section, 58
degrees leading-edge sweep (4 at the exit
wing border) and moderately
blended root; area-ruled; two small canard wings, fixed, placed just behind the air intakes.
The flight commands on the wing are: four elevons (+15/-30°), four slats, four airbrakes (2
above and 2 below each wing).
Its neutral point is in front of its center of gravity, giving the fighter relaxed stability to
enhance maneuverability. It was the first fighter jet to incorporate negative stability and
fly-by-wire controls in its design. An airbrake is fitted on top and below each wing in an
arrangement very similar to that of the Mirage III. A noticeably taller tailfin allows the
pilot to retain control at higher angles of attack, assisted by small strakes mounted along
each air intake.
It has a runway arresting hook or fairing for a brake parachute can be fitted under the tail.
The landing roll was reduced by robust carbon brakes. The backward-retracting, steerable
nose gear features dual wheels, while the main gear features single wheels and retracts
inward into the wings. A parachute brake is on the tail, just above the engine exhaust.
A fixed removable refueling probe can be attached in front of the cockpit, offset slightly to
the right of center.

14. AVIONICS DIVISION, KORWA IS INVOLVED IN THE MANUFACTURE OF
ADVANCED AVIONICS
SYSTEMS LIKE INERTIAL
NAVIGATION
SYSTEM(INS),COMBINED MAP
AND ELECTRONIC
DISPLAY(COMED),HEAD UP
DISPLAY & WEAPON AIMING
COMPUTER(HUDWAC),LASER
RANGER AND MARKED
TARGET
SEEKER(LRMTS),AUTOSTABILI
ZER AND FLIGHT DATA
RECORDER(FDR).
THE DIVISION HAS ALSO ESTABLISHED THE FACILITIES FOR DEPOT
LEVEL MAINTENANCE FACILITIES FOR DIGITAL MAP GENERATOR
(DMG), HEAD UP DISPLAY (HUD) FOR JAGUAR AND SU-30 AIRCRAFT
AND PRODUCTION FACILITIES FOR MANUFACTURE OF MULTI
FUNCTION DISPLAY(MFD) FOR SU-30 MKI AIRCRAFT.

15. Products in Current Manufacturing Range
Currently the Korwa Division manufactures the Navigation, Ranging, Display and
Attack Systems for both Jaguar and MiG-27M aircraft.
Brief details of the avionic system are as under:
JAGUAR AVIONICS
 Inertial Navigation System
o Stabilized Inertial Platform with Dry-tuned Gyroscopes and
Accelerometers
o Digital Nav-Attack Computer
o Interface Unit and Cockpit Control Panels
 Head-Up Display & Weapon Aiming Computer (HUDWAC)
o Microprocessor based head-up
Display & Sighting System
o Scan and Cursive modes of display
o Weapon Aiming Computations in
Reversionary modes in the event of
failure of INS Computer

16. o Head Down Navigation & Map
Display
o Soft key Selectable Display
Modes
o Integrated with INS and HUDWAC on MIL-STD 1553B Digital Data
Bus
 Flight Data Recorder (FDR)
o Crash protected Flight Data Recording System with Data Acquisition
Unit
o Simultaneous recording of Data and Audio tracks
o Recording duration of 90 minutes in endless loop
 Laser Ranger and Marked Target Seeker (LRMTS)
o Operates both in Ranging and Target Seeking modes
o Target Range Computation
o Neodymium Doped YAG Laser
 Autostabliser System (AUTOSTAB)
o Computer Based System for Control of Tailplane, Rudder and Spoiler
Movements
o Incorporate BITE Facility

17. MiG-27M AVIONICS
Integrated Navigation and Sighting Complex
(44 LK System)
 Inertial Navigation System
 Centralized Digital Computer
 Radio and Doppler Navigation
 Stabilised Sight
 Air Data Computer
 Laser Ranging System
Flight Data Recorder (UZL TESTER)
 Recording Duration of 3 Hours
 Crash Protected Recording System
 Records 38 Analogue and 32 Discrete Parameters

18. DEPARTMENTS
Departments under HAL Korwa are categorized for the proper functioning of the
division. These departments have their functional heads supported by other
executives and workers. The functional heads report directly to General Manager
who in turn reports to respective MD.
These departments are as follows:
Assembly and Testing (MIG)
Manufacturing
Assembly and Testing (Jaguar)
Tool Design
STEG
Management Services Department
Design
Vigilance
Commercial and Purchase
Civil;
Process Shop;
Finance/ Account;

19. Training Department;
Plant Maintenance;
Quality Control;
Admin and Personnel;
Computer Section;
Security;
Su-30

20. SPECIAL TEST EQUIPMENT
GROUP (S.T.E.G.)
Testing of Equipment’s
1. Transistor
2. Resistance
3. Diode
4. Capacitor
The special to type test equipment group (STEG) at HAL Korwa has been involved
in Design, fabrication and maintenances of various kinds of special to type test
equipment. This play a vital role in the house development of different test
equipment, test rigs, jigs and fixtures, high vacuum systems and optical test
benches for testing of precision gyros, accelerometers and associated electronics.
Equipment designed developed at STEG are in regular use at various avionics
labs, testing of LRU in assembly shops of our division, air fours bases throughout
the country and other division .Accordingly this department has been nominated as
a nodal agency for making of test equipment for other divisions. This group also
provides maintenance support of standard test equipment and test equipment
manufactured by the department to the division.
This department is the backbone of H.A.L. as it the main group of Quality Control.
This is the main group which involves testing of electronic equipments and
instruments used in the factory. All the equipments of the factory are tested and
calibrated against the working standard. These standards are compatible to the
N.P.L. Standards. All those equipments, which fail in the tests, are repaired.
So at the functional point of view, this department is divided into two main groups.
1. Calibration Lab.
2. Repair Shop

21. S.T.E.G. is also involved in the production of new
instruments used in Avionics.
1. CALIBRATION LAB: This is the lab where the different instruments and
equipment are calibrated against the working standards and ideal standards
under the ideal physical conditions from all the different departments of the
H.A.L. the electronics instruments are rushed here for calibration.
2. REPAIR SHOP: This lab is mainly concerned with repair of damaged
electronic equipments from any part of the factory. The basic strategy
followed is cold testing of each component such as diode, transistor, relays,
IC’s. Once found faulty, they are replaced and again the output is checked.
SPECIAL TEST EQUIPMENT GROUP (S.T.E.G.)
The special to type test equipment group (STEG) at HAL Korwa is involved in
fabrication and maintenance of various kinds of “special to type test
equipment”.
The Objective of STEG Department is as follows :
 Design, Modification and manufacture of Special Type Test Equipment
(STTE)
 Repair and servicing of commercial, Standard Test Equipment &
indigenously manufactured test equipment for various shops over the
years.

22. The main activities of STEG (Special Test Equipment Group) includes:
1. Scrutinize the work order for the production of test equipments.
2. Fabrication, Production and maintenance of test equipments.
3. To develop in house test equipments like Test Rigs, Optical test benches,
High Vacuum systems, for testing of precision instrument such as Gyros,
Accelerometer and associated electronics etc.
4. To provide maintenance support of standard test equipments.
5. Procurement action for spare parts.
6. Outsourcing of repair of Special Test Equipments.
Various types of Special type Test Equipments STEG are produced in STEG
catering to different requirements:
 O-LEVEL (Operational level)
These benches are meant for 1st
level maintenance of units at Air
bases and are of GO/NOGO type which gives the output whether unit
under test is PASS/FAIL.
 I-LEVEL(Intermediate level)
It is meant for fault diagnosis/functionality testing up-to Module
level at (Assembled PCB) level.

23.  D-LEVEL ( Depot level)
It is meant for fault diagnosis/functionality testing up-to component
level and it is primarily used for component level repair of the
PCBs/Module. This type of Test equipments are essential for repair
agencies/OEM for detail investigation & repair.

24. PROJECT:
To study various electronic measuring equipments used in STEG
Following equipments has been studied:
1. DRU(Data Retrieval Unit)
2. Digital Multi-meter
3. Cathode Ray Oscilloscope
4. Function Generators
5. Power supplies
Data Retrieval Unit
This test bench is presently under development/manufacturing by STEG. It
is used for testing of various parameters of SSFDR like power supply,
frequency parameter, analog parameter, data recording and retrieval etc.
The bench is fully designed & developed in-house at KORWA. All
mechanical parts (chassis) are fabricated in-house tool room. PCB
assembly/wiring/interconnections are done at STEG.

25. Ground Replay Equipment (GRE) :
The real-time data of various aircraft parameters recorded in the Flight Data
Recorder (FDR) are downloaded and replayed on the ground with the help of the
GRE. The application software will run on the Host PC (GRE) and will acquire the
recorded data from the FDR through Asynchronous serial communication link
(RS422). A suitable adapter card with suitable device driver software is used to
access this asynchronous serial communication channel (RS422) through the USB
port.
The time tag information recorded on FDR is used as an absolute reference. The
recorded data acquired from the FDR is stored in the hard disk in prescribed format
for further analysis and retrieval.
The proposed system consists of the following.
1. A Laptop system.
2. A USB RS422 adaptor.
3. Printer.
4. Power Supply Unit.
5. Battery Backup.
6.
RS 422
CONVERTER
FLIGHT
DATA
RECORDER
POWER SUPPLY
PRINTER
LAPTOP

26. EXTERNAL INTERFACE
3. REPAIR GROUP:
This lab is mainly concerned with repair of damaged electronic equipments
from any part of the factory. The basic strategy followed is cold testing of each
component such as diode, transistor, relays, IC’s. Once found faulty, they are
replaced and again the output is checked.

27. A flight data recorder (FDR) (also ADR, for accident data recorder) is a kind of
flight recorder. It is a device used to record specific aircraft performance
parameters. Another kind of flight recorder is the cockpit voice recorder (CVR),
which records conversation in the cockpit, radio communications between the
cockpit crew and others (including
conversation with air traffic control
personnel), as well as ambient
sounds. In some cases, both functions
have been combined into a single
unit. The current applicable FAA
TSO is C124b titled Flight Data
Recorder Systems.
Popularly referred to as a "black
box," the data recorded by the FDR is used for accident investigation, as well as for
analyzing air safety issues, material degradation and engine performance. Due to
their importance in investigating accidents, these ICAO-regulated devices are
carefully engineered and stoutly constructed to withstand the force of a high speed
impact and the heat of an intense fire. Contrary to the "black box" reference, the
exterior of the FDR is coated with heat-resistant bright Red paint for high visibility
in wreckage, and the unit is usually mounted in the aircraft's empennage (tail
section), where it is more likely to survive a severe crash.
DESIGN
The design of today's FDR is governed by the internationally recognized standards
and recommended practices relating to flight recorders which are contained in
ICAO Annex 6 which makes reference to industry crashworthiness and fire
protection specifications such as those to be found in the European Organisation
for Civil Aviation Equipment documents EUROCAE ED55, ED56 fiken A and
ED112 (Minimum Operational Performance Specification for Crash Protected
Airborne Recorder Systems). In the United States, the Federal Aviation
Administration (FAA) regulates all aspects of U.S. aviation, and cites design

28. requirements in their Technical
Standard Order, based on the
EUROCAE documents (as do the
aviation authorities of many other
countries).
Currently, EUROCAE specifies that a
recorder must be able to withstand an
acceleration of 3400 g (33 km/s²) for
6.5 milliseconds. This is roughly equivalent to an impact velocity of 270 knots
(310 mph) and a deceleration or crushing distance of 450 cm. Additionally, there
are requirements for penetration resistance, static crush, high and low temperature
fires, deep sea pressure, sea water immersion, and fluid immersion
GROUND REPLAY EQUIPMENT:
The real-time data of various aircraft parameters recorded in the Flight Data
Recorder (FDR) are downloaded and replayed on the ground with the help of the
GRE.the application software will run on the host PC (GRE)and will acquire the
recorded that from the FDR through asynchronous serial communication link
(RS422). A suitable adapter card with suitable device driver software is used to
access this asynchronous serial communication channel (RS422) through the usb
port.
The time tag information recorded on FDR is used as an absolute reference.the
recorded data is acquired from the FDR is stored in the hard disk in prescribed
format for futher analysis and retrieval.
the proposed system consists of the following:
 A laptop system
 A USB RS422 adaptor
 Printer
 Power supply unit
 Battery back up.

29. PRINTER LAPTOP
RS 422
CONVERTER
BATTERY BACKUP
FLIGHT DATA
RECORDER
POWER SUPPLY

30. PROJECT:
To study various electronic meteorological measurement equipments.
INTRODUCTION:
Today in the present era, in every industry there is need of electronic
gadgets. Without these equipment’s the work would really be impossible. For
better accuracy sophisticated equipment’s are used. So my area of project covers
all the most sophisticated electronic equipment’s that are used in every generators,
Digital millimeters, Counters and Power supplies.
SCOPE:
These equipments are studied and limited to following scope:
o Operation and function.
o Specification and accuracies.
o Block diagram and working principles.
o Calibration needs.

31. The following equipments are studied in this project are:
 Various types of Digital Multimeter
(HP34401).
 Various types of CRO’s (TEKTRONICS).
 Function Generators (HELWETT
PACKERD).
 Various power supplies (HIL, APLAB).
CAPACITOR CODING
Capacitor Number Code
A number code is often used on small capacitors where printing is difficult:
 the 1st number is the 1st digit,
 the 2nd number is the 2nd digit,
 the 3rd number is the number of
zeros to give the capacitance in pF.
 Ignore any letters - they just
indicate tolerance and voltage
rating.
Capacitor Colour Code
A colour code was used on polyester
capacitors for many years. It is now
obsolete, but of course there are many
still around. The colours should be read like the resistor code, the top three colour
bands giving the value in pF. Ignore the 4th band (tolerance) and 5th band (voltage
rating).

32. Printed circuit board
A printed circuit board, or PCB, is used to mechanically support and electrically
connect electronic components using conductive pathways, tracks or signal traces
etched from copper sheets laminated onto a non-conductive substrate. It is also
referred to as printed wiring board (PWB) or etched wiring board. A PCB
populated with electronic components is a printed circuit assembly (PCA), also
known as a printed circuit board assembly (PCBA).
PCBs are inexpensive, and can be highly reliable. They require much more layout
effort and higher initial cost than either wire-wrapped or point-to-point constructed
circuits, but are much cheaper and faster for high-volume production.
Manufacturing
Materials:
Conducting layers are typically made of thin copper foil. Insulating layers
dielectric are typically laminated together with epoxy resin prepreg. The board is
typically coated with a solder mask that is green in color. Other colors that are
normally available are blue and red. There are quite a few different dielectrics that
can be chosen to provide different insulating values depending on the requirements
of the circuit. Some of these dielectrics are polytetrafluoroethylene (Teflon), FR-4,
FR-1, CEM-1 or CEM-3.
Patterning (etching):
The vast majority of printed circuit boards are made by bonding a layer of copper
over the entire substrate, sometimes on both sides, (creating a "blank PCB") then
removing unwanted copper after applying a temporary mask (e.g. by etching),
leaving only the desired copper traces. A few PCBs are made by adding traces to
the bare substrate (or a substrate with a very thin layer of copper) usually by a
complex process of multiple electroplating steps.
There are three common "subtractive" methods (methods that remove copper) used
for the production of printed circuit boards:
1. Silk screen printing uses etch-resistant inks to protect the copper foil.
Subsequent etching removes the unwanted copper. Alternatively, the ink

33. may be conductive, printed on a blank (non-conductive) board. The latter
technique is also used in the manufacture of hybrid circuits.
2. Photoengraving uses a photo mask and chemical etching to remove the
copper foil from the substrate. The photo mask is usually prepared with a
photo plotter from data produced by a technician using CAM, or computer-
aided manufacturing software. Laser-printed transparencies are typically
employed for photo tools; however, direct laser imaging techniques are
being employed to replace photo tools for high-resolution requirements.
3. PCB milling uses a two or three-axis mechanical milling system to mill
away the copper foil from the substrate. A PCB milling machine (referred to
as a 'PCB Prototyper') operates in a similar way to a plotter, receiving
commands from the host software that control the position of the milling
head in the x, y, and (if relevant) z axis. Data to drive the Prototyper is
extracted from files generated in PCB design software and stored in HPGL
or Gerber file format
4. Lamination
5. Some PCBs have trace layers inside the PCB and are called multi-layer
PCBs. These are formed by bonding together separately etched thin boards.
Drilling:
Holes through a PCB are typically drilled with tiny drill bits made of solid tungsten
carbide. The drilling is performed by automated drilling machines with placement
controlled by a drill tape or drill file. These computer-generated files are also
called numerically controlled drill (NCD) files or "Excellon files". The drill file
describes the location and size of each drilled hole. These holes are often filled
with annular rings (hollow rivets) to create vias. Vias allow the electrical and
thermal connection of conductors on opposite sides of the PCB.
Exposed conductor plating and coating:
PCBs are plated with solder, tin, or gold over nickel as a resist for etching away the
unneeded underlying copper.
Matte solder is usually fused to provide a better
bonding surface or stripped to bare copper. Treatments, such as
benzimidazolethiol, prevent surface oxidation of bare copper. The places to which
components will be mounted are typically plated, because untreated bare copper
oxidizes quickly, and therefore is not readily solderable. Traditionally, any exposed
copper was coated with solder by hot air solder leveling (HASL). This solder was a
tin-lead alloy, however new solder compounds are now used to achieve
compliance with the RoHS directive in the EU and US, which restricts the use of
lead. One of these lead-free compounds is SN100CL, made up of 99.3% tin, 0.7%
copper, 0.05% nickel, and a nominal of 60ppm germanium.

34. Solder resist:
Areas that should not be soldered may be covered with a polymer solder resist
(solder mask) coating. The solder resist prevents solder from bridging between
conductors and creating short circuits. Solder resist also provides some protection
from the environment. Solder resist is typically 20-30 microns thick.
Screen printing:
Line art and text may be printed onto the outer surfaces of a PCB by screen
printing. When space permits, the screen print text can indicate component
designators, switch setting requirements, test points, and other features helpful in
assembling, testing, and servicing the circuit board.
Screen print is also known as the silk screen, or, in one sided PCBs, the red print.
Printed circuit assembly:
After the printed circuit board (PCB) is completed, electronic components must be
attached to form a functional printed circuit assembly, or PCA (sometimes called a
"printed circuit board assembly" PCBA). In through-hole construction, component
leads are inserted in holes. In surface-mount construction, the components are
placed on pads or lands on the outer surfaces of the PCB. In both kinds of
construction, component leads are electrically and mechanically fixed to the board
with a molten metal solder.

35. SOLDERING
Soldering is a process in which two or
more metal items are joined together by
melting and flowing a filler metal into the
joint, the filler metal having a relatively
low melting point. Soft soldering is
characterized by the melting point of the
filler metal, which is below 400 °C
(752 °F).[1]
The filler metal used in the
access is called solder.
APPLICATIONS
One of the most frequent applications of soldering is assembling electronic
components to printed circuit boards (PCBs). Another common application is
making permanent but reversible connections between copper pipes in plumbing
systems. Joints in sheet metal objects such as food cans, roof flashing, rain gutters
and automobile radiators have also historically been soldered, and occasionally still
are. Jewelry components are assembled and repaired by soldering. Small
mechanical parts are often soldered as well. Soldering is also used to join lead
came and copper foil in stained glass work. Soldering can also be used as a semi-
permanent patch for a leak in a container or cooking vessel.
SOLDER
Common solder alloys are mixtures of tin and lead, respectively:
 63/37: melts at 183 °C (361 °F) (eutectic: the only mixture that melts at a
point, instead of over a range)
 60/40: melts between 183–190 °C (361–374 °F)
 50/50: melts between 185–215 °C (365–419 °F)

36. FLUX
In high-temperature metal joining processes (welding, brazing and soldering), the
primary purpose of flux is to prevent oxidation of the base and filler materials. Tin-
lead solder, for example, attaches very well to copper, but poorly to the various
oxides of copper, which form quickly at soldering temperatures. Flux is a
substance which is nearly inert at room temperature, but which becomes strongly
reducing at elevated temperatures, preventing the formation of metal oxides.
Secondarily, flux acts as a wetting agent in the soldering process, reducing the
surface tension of the molten solder and causing it to better wet out the parts to be
joined.
BASIC SOLDERING TECHNIQUES:
Soldering operations can be performed with hand tools, one joint at a time, or en
masse on a production line. Hand soldering is typically performed with a soldering
iron, soldering gun, or a torch, or occasionally a hot-air pencil. Sheetmetal work
was traditionally done with "soldering coppers" directly heated by a flame, with
sufficient stored heat in the mass of the soldering copper to complete a joint;
torches or electrically-heated soldering irons are more convenient. All soldered
joints require the same elements of cleaning of the metal parts to be joined, fitting
up the joint, heating the parts, applying flux, applying the filler, removing heat and
holding the assembly still until the filler metal has completely solidified.
Depending on the nature of flux material used, cleaning of the joints may be
required after they have cooled.

37. PIPE SOLDERING:
Copper pipe, or 'tube', is commonly joined by soldering. Copper is an outstanding
conductor of heat, therefore it requires more heat than a soldering iron or gun can
provide, so a propane torch is most commonly used; for large jobs a MAPP or
acetylene torch is used.
Solder fittings, which are short sections of smooth pipe designed to slide over the
outside of the mating tube, are usually used for copper joints. There are two types
of fittings: end feed fittings which contain no solder, and solder ring fittings, in
which there is a ring of solder in a small circular recess inside the fitting.
DESOLDERING:
Used solder contains some of the dissolved base metals and is unsuitable for reuse
in making new joints. Once the solder's capacity for the base metal has been
achieved it will no longer properly bond with the base metal, usually resulting in a
brittle cold solder joint with a crystalline appearance.
It is good practice to remove solder from a joint prior to resoldering—desoldering
braids or vacuum desoldering equipment (solder suckers) can be used. Desoldering
wicks contain plenty of flux that will lift the contamination from the copper trace
and any device leads that are present. This will leave a bright, shiny, clean junction
to be resoldered.
The lower melting point of solder means it can be melted away from the base
metal, leaving it mostly intact, though the outer layer will be "tinned" with solder.
Flux will remain which can easily be removed by abrasive or chemical processes.
This tinned layer will allow solder to flow into a new joint, resulting in a new joint,
as well as making the new solder flow very quickly and easily.

38. SOLDERING DEFECTS:
Some of the common soldering defects are:
 Cold Joint
 Fractured Joint
 Improperly bonded joints
 Excessive / Less solder
 Rosin Joint
 Wetting / Non wetting
 Pin holes / Blowholes

39. DO‫׳‬S
1. TO be ensure that the input voltage of 230vac, ±10v of 50Hz is present in
clean room.
2. Take to care avoid short circuit & with measuring clip & hooks if the
instruments is switched ON, near input terminal when high voltage are
present.
3. Fault finding activities are started read the instruction about Before
switching ON the test equipment whenever operation /servicing /
maintenance procedure.
4. Maintain the norms of IS/ISO 1400-2004(environmental control)
5. During soldering & dislodging period keep temp. of soldering /disordering
station to the optimum value i.e. 300degreeC ±5dehreeC approx. always use
lead free solder.
6. Use only original /equipment spare parts. The spare should be checked
before replacement of them during repairing of equipments.
7. Ensure that all working station should be prepared with all types of
measuring equipments with testing accessories in calibrated condition.
8. Before attempting to repair of equipment it is necessary to read the nature of
fault given by user in repair.
9. After production /repairing /maintenance of the test equipment must be
calibrated in calibration lab. After calibration of equipments will be send to
user (shop) agency.
10. Routine calibration of test equipments to be updated.

40. DONT’S
1. Don’t start the equipment ´ON in uncontrolled atmospheric condition of
clean room.
2. No equipment will be switched ´ON´/start in beyond suggested
tolerance/limit of input supply voltage.
3. During testing of the high voltage 500V-25000V at least two operators
should available to the workstation.
4. Don’t start faultfinding /repair maintenance of test equipment without
reading the operation /servicing/maintenance manual.
5. No wastages like cleaning reagents , expired consumable & plastic should
not be scattered on roof because it disturb to the norms of ISO 1401-2004.
6. During soldering /disordering period don’t keep the temp. of the soldering
station beyond given range , item cane damage /burst/burnt or loose their
original value.
7. Don’t use spare parts on random selection basis as may it cause failure of
test equipments.
8. Don’t use wrong /faulty measuring equipment with improper accessories
during production /repair of equipments.
9. Nature of fault must be diagnosed at first ,because most of the time
consumed by operator, Secondly it is also very harmful for operator’s daily
man hours calculation.

41. 10. Don’t send the production /repairing /maintenance of test equipment/items
to user without calibration. because the non-calibrated equipment gives
wrong results , which is dangerous for testing of modules/unit.
11. Without routine calibration of equipments wrong readings are obtained
which may results failure of the modules as per testing procedures.