Antennas Practice Test 8

1. Log periodic antenna uses which range of frequencies?

HF and VHF

VHF and UHF

VHF and SHF

MF and VHF

2. Height criteria required for mounting AUT under elevated range test is ______

h_r ≥ 2D

h_r ≥ 4D

h_r ≤ 4D

h_r ≤ 2D

3. Log periodic antenna is frequency dependent.

True

False

4. The empirical formula for the measurement of the high VSWR is give by ____

\(VSWR =\frac{λ_g}{π(d_2-d_1)}\)

\(VSWR =\frac{2λ_g}{(d_2-d_1)}\)

\(VSWR =\frac{λ_c}{π(d_2-d_1)}\)

\(VSWR =\frac{λ_g}{2(d_2-d_1)}\)

5. The value of periodicity factor in LPDA is _____

< 1

≥1

6. Which of the following level can be measurable by the Low VSWR?

7. In order to get more number of channels in TV reception, we prefer Yagi-Uda than LPDA.

False

True

8. Which of the following equation holds good for gain transfer method?

G_{test antenna} / G_{std antenna}) = \(10log⁡(\frac{P_{Test}}{P_{Std}}) \)

G_{test antenna} = G_{std antenna}) + \(10log⁡(\frac{P_{Test}}{P_{Std}}) \)

G_{test antenna} + G_{std antenna}) = \(10log⁡(\frac{P_{Test}}{P_{Std}}) \)

G_{test antenna} = G_{std antenna}) - \(10log⁡(\frac{P_{Test}}{P_{Std}}) \)

9. In normal mode of operation, the radiation is along the end-fire direction.

True

False

10. The dipoles in the inactive transmission region offer ________ impedance.

Resistive

Characteristic

Capacitive

Inductive