A conductor in a printed circuit should be considered a transmission line if its length l (in meters) is
l > Tr/100 nsec ( Tr- rise time of pulse) 0%
l > 2Tr/100 nsec 0%
l > Tr/200 nsec 0%
l > 2Tr/50 nsec 0%
A standard hole(0.8mm) in a PCB design is represented by which symbol.
All the processing steps for manufacturing ultra thin foils except ____are conventional.
drilling 0%
aluminium foil removal 0%
fortification 0%
etching 0%
By which material is the transfer of the conductor pattern from the film master on to the copper clad base material done?
Photo printing 0%
Hand printing 0%
Screen printing 0%
Both a and c 0%
By which material is the typical resin/filler laminate of ordinary PCBs replaced in metal core boards?
Sheet metal covered with insulation material 0%
Cardboard 0%
Foil with insulation 0%
None of the above 0%
Copper plating is done in multilayer boards to _____.
remove etchants 0%
remove excess copper 0%
withstand thermal shock due to soldering 0%
clean a PCB with chemicals 0%
Crosstalk is much less dangerous in which of the following.
ECL-ICs 0%
TTL-ICs 0%
RTL-ICs 0%
CMOS -ICs 0%
Current spikes in TTL circuit boards can be eliminated by which technique.
removing the TTL circuit 0%
replacing transistors with diodes 0%
using a ground line 0%
All of the above 0%
Etch back is a technique by which ______.
epoxy smear is removed and the exposed glass fibers prepared for copper deposition 0%
epoxy smear is deposited and the exposed glass fibers prepared for copper removal 0%
etchants are removed again 0%
None of the above 0%
Fabrication of PCBs for microwave use requires
VSWR > 1 0%
VSWR < 1 0%
VSWR exactly 1 0%
VSWR equal to zero 0%
Ferric chloride is used in PCB designing as a/an _____.
resist 0%
etchant 0%
board cleaner 0%
a soldering material 0%
For the etching process, the temperature should preferably be around
30°C 0%
10°C 0%
45°C 0%
100°C 0%
For TTL , we require a wave impedance of_____.
50-100ohm 0%
100-150ohm 0%
150-200ohm 0%
200-250ohm 0%
How much copper surface is reserved on multilayer boards for the solderability test?
20×70 mm 0%
10×50 mm 0%
20×70 cm 0%
10×50 cm 0%
If Ohmic losses are neglected, the wave impedance Zw in a homogenous material can be calculated by using the formula.
Zw =(L/C)1/2 0%
Zw =(2L/C)1/2 0%
Zw =(2C/L)1/2 0%
Zw =(C/L)1/2 0%
If a ground line is kept close to a signal line, crosstalk would be _____.
In fast signal or high – speed logic circuits , the conductors are considered to be _____.
impedances 0%
transmission lines 0%
capacitors 0%
inductors 0%
In the component code used in the circuit diagram, by which letter, according to ANSI, is an integrated circuit represented?
In the layout approach, a 'Puppet' is used for_____.
a diode 0%
a transistor 0%
an IC 0%
any commonly used electronic component 0%
In which of the following processes is porosity test done?
Plating 0%
Etching 0%
Cleaning 0%
Film master preparation 0%
In which of the following ways can the required quantity of heat for the melting of the solder be supplied?
Iron soldering 0%
Hot gas soldering 0%
Radiant heat soldering 0%
All of the above 0%
It is a common experience of electronic circuit designers that at high frequency{>10 MHz), amplifiers behave as _____.
oscillators 0%
tuned amplifiers 0%
feedback amplifiers 0%
Inverters 0%
Large values of wave impedance call for _____.
broader signal conductors 0%
thin signal conductors 0%
both a and b 0%
Multiwire boards are used in
the implementation of high density electronic circuits 0%
the implementation of low density electronic circuits 0%
the implementation of power electronic circuits 0%
the implementation of power supply circuits 0%
On a PCB, the low power part and the high power part have to be spread sufficiently to avoid _____.
capacitive and inductive coupling between power circuits 0%
crosstalk 0%
only inductive coupling 0%
only capacitive coupling 0%
Parasitic effects influence the working of a PCB.
true 0%
false 0%
sometimes true and sometimes false 0%
Polymeric materials exhibit a very high resistance to
temperature variations 0%
pressure 0%
humidity 0%
elasticity 0%
Removing the resists from the board in photo printing is called
Post backing 0%
stripping 0%
touch up 0%
dyeing 0%
Screen printing is used in _____.
photo printing 0%
screen printing 0%
hand printing 0%
All of the above 0%
Self soldering or soldering generally implies that the joining process occurs at temperatures below
100°c 0%
200°c 0%
350°c 0%
450°c 0%
The absolute dimensional accuracy of a film master is determined by
the accuracy of the original artwork 0%
the dimensional stability of the artwork 0%
the reduction scale of the artwork to the actual PCB size 0%
All of the above 0%
The analog and the digital circuit on the same PCB should have _____.
common ground conductor networks 0%
independent ground conductor networks 0%
no ground conductor network 0%
None of the above 0%
The biggest disadvantage of flexible PCBs is that
they can not be used for low frequency applications 0%
they are not suitable for high frequency applications 0%
they can be used only in military applications 0%
they can used only in aerospace applications 0%
The biggest problem associated with striplines and microstrip lines is the
low attenuation per unit length 0%
high attenuation per unit length 0%
low impedance per unit length 0%
high impedance per unit length 0%
The dielectric constant of any material is also referred to as _____.
permeability 0%
permittivity 0%
proximity 0%
resistivity 0%
The fundamental principle of electrolysis is understood from
Ampere's law 0%
Faraday's law 0%
Ohm's law 0%
Coulomb's law 0%
The inks used in screen printing are mostly
acid based 0%
alkali based 0%
vinyl based 0%
All of the above 0%
The microstrip line is derived from a _____.
conductor on the ground 0%
conductor below the ground 0%
conductor above the ground 0%
None of the above 0%
The skin-effect losses are sometimes also called
semiconductor losses 0%
conductor losses 0%
insulator losses 0%
None of the above 0%
The volume resistivity of a laminate is given by
R*A / l R- resistance measured 0%
R*l / A A-area of gourde electrode (cm2) 0%
A*l / R l-thickness of sample(cm) 0%
R / A*l 0%
To overcome the motorboating effect, we must _____.
do decoupling of power supply conductors with sufficiently large capacitors 0%
do decoupling of power supply conductors with small capacitors 0%
not to do any decoupling 0%
To reduce the skin-effect losses, what is required to be done.
decrease PCB – thickness 0%
increase PCB thickness 0%
keep line length large 0%
None of the above 0%
Ultra thin copper foil has a range of thickness varying from
5-10cm 0%
5-10mm 0%
5-10um 0%
5-10nm 0%
Under etching can be minimized by keeping the etching time _____.
as short as possible 0%
as long as possible 0%
equal to 5 minutes 0%
equal to 30 seconds 0%
Under which of the following conditions is a multilayers board used?
Where the overall PCB dimensions and interconnections are not feasible on a double-sided PCB 0%
Where reduction in electronic equipment weight and volume is the prime concern 0%
Where decoupling and shielding of the interconnections is important 0%
All of the above 0%
What is hot air leveling used for?
Etching 0%
PCB finishing 0%
PCB layout 0%
PCB artwork 0%
What would be the simplest and most suitable remedy for electro-magnetic coupling between two wires?
To increase the space between two wires 0%
To increase the lamination between two wires 0%
To twist the both wires 0%
To decrease the spacing between two wires 0%
When two transmission lines are placed close to each other, they are said to be coupled. This coupling can be used to built
band pass filters 0%
band elimination filters 0%
directional couplers 0%
All of the above 0%
Which size of rack is used as a standard rack in PCB design?
18" 0%
19" 0%
20" 0%
21" 0%
Which of the following can be called multilayer construction?
Clearance holes 0%
Plated through holes 0%
Fused tubelets or eyelets 0%
All of the above 0%
Which of the following is a base material used in the manufacturing of flexible PCBs?
Epoxy resin 0%
Polyester foil 0%
Teflon foil 0%
All of the above 0%
Which of the following is a category of dry film resists?
Solvent developing dry film resists 0%
Liquid developing dry film resists 0%
Hand developing dry film resists 0%
All of the above 0%
Which of the following is a characteristic parameter of a photographic material?
Density 0%
Resolving power 0%
Exposure latitude 0%
All of the above 0%
Which of the following is a coating process for wet film resists?
Flow coating 0%
Roller coating 0%
Dip coating 0%
All of the above 0%
Which of the following is a design constraint for the design of the flexible PCBs?
Current carrying capacity of the conductors 0%
Bending 0%
Contours 0%
All of the above 0%
Which of the following is a disadvantage of a solder mask?
Less contamination of the solder alloy 0%
Avoidance of solder bridging 0%
Its capability with the flux has to be verified before use 0%
Improved flexural strength 0%
Which of the following is a mechanical machining operation on PCBs?
Shearing 0%
Sawing 0%
Punching 0%
All of the above 0%
Which of the following is a solderability test method?
Solder bath test 0%
Solder globule test 0%
Surface tension balance test 0%
All of the above 0%
Which of the following is a technique for the generation of the circuit pattern on metal core boards?
Substance additive processing 0%
Additive processing with catalytic adhesive 0%
Semi-additive processing 0%
Both a and b 0%
Which of the following is a type of soldering fluxes?
Corrosive fluxes 0%
Intermediate fluxes 0%
Non-corrosive fluxes 0%
All of the above 0%
Which of the following is not a basic ingredient of a copper clad laminate?
Filler 0%
Resin 0%
Silver foil 0%
Copper foil 0%
Which of the following is not a film used in PCB design?
A copper film 0.0%
A polyester film 0.0%
A photographic glass 100.0%
A tri-acetate film 0.0%
Which of the following is not a machine cleaning process for boards?
Sanding 0%
Water rinse 0%
Wet brushing 0%
Scrubbing 0%
Which of the following is not a physical characteristic of a copper clad laminate?
Flame resistance 0%
Water absorption 0%
Flexural strength 0%
Color 0%
Which of the following is not a solder alloy?
Tin lead 0%
Tin antimony 0%
Tin silver 0%
Iron lead 0%
Which of the following techniques is used in mass soldering?
Dip soldering 0%
Drag soldering 0%
Wave soldering 0%
All of the above 0%
Which of the following tests is done for quality control for multilayer boards?
Electrical and metallographic test 0%
Continuity between layers test 0%
Insulation resistance between layers test 0%
All of the above 0%
Which one of the following is not a plating technique?
Immersion plating 0%
Electroless plating 0%
Hard plating 0%
Electroplating 0%