ISRO Scientist or Engineer Electronics 2012
For the following questions answer them individually
ISRO Scientist or Engineer Electronics 2012 - Question 51
The RF amplifier A is having 3 dB NF & 5 dB ofgain, amplifier B is having 3.5 dB NF & 15 dB. For overall noise figure of the cascaded system, the correct statementis :
ISRO Scientist or Engineer Electronics 2012 - Question 52
For this RF Circuit, the correct statement is :
ISRO Scientist or Engineer Electronics 2012 - Question 53
The gain of a parabolic dish antenna of 1 m diameterand 80% efficiency at 9.5 GHzis :
ISRO Scientist or Engineer Electronics 2012 - Question 54
In a uniform linear array, four isotropic radiating elements are spaced $$\frac{\lambda}{4}$$ apart. The progressive phase shift between the elements required for forming -
the main beam at $$60^\circ $$ of the end fireis:
ISRO Scientist or Engineer Electronics 2012 - Question 55
The radiation resistance of a thin line centre fed A/2 antenna with sinusoid currentdistributionis :
ISRO Scientist or Engineer Electronics 2012 - Question 56
To increase gain of a parabolic reflector antenna by 6dBi, the correct
ISRO Scientist or Engineer Electronics 2012 - Question 57
The waveguide Magic Tee can be used as:
ISRO Scientist or Engineer Electronics 2012 - Question 58
The microwave device working on the principal of Faradayrotation is called as:
ISRO Scientist or Engineer Electronics 2012 - Question 59
The phase difference between adjacent anode poles of Magnetron is generally:
ISRO Scientist or Engineer Electronics 2012 - Question 60
Which of the following devices cannot be used as microwaveoscillator:
