ESAT Pre-Board Exam 18

What determines the bandwidth of a transmitted AM signal?

• the maximum modulation amplitude
• the lowest frequency component of the intelligence
• the lowest modulation amplitude
• the highest frequency of the modulating signal

A receiver has two uncoupled tuned circuits before the mixer, each with a Q of 75. The signal frequency is 100.1 MHz, and the IF is 10.7 MHz. The local oscillator uses low-side injection. Calculate the image rejection ratio in dB.

• 58.60 dB
• 29.30 dB
• 62.48 dB
• 31.24 dB

If the SWR is equal to one, what type of load transmission line has?

• purely reactive
• purely resistive
• purely capacitive
• purely inductive

Waveguides are generally used above ______.

• 20 MHz
• 100 MHz
• 200 MHz
• 1000 MHz

Which of the following is most often transmitted in a binary (two-level) digital mode?

• USB emission
• ISB emission
• FSTV emission
• CW emission

An important operational point in the SPADE system is that the carriers are _____.

• voice operated
• suppressed
• filtered
• always present

Which of the following is not necessarily an advantage of FM over AM?

• less modulation power is required
• lower bandwidth is required
• better noise immunity
• the transmitted power is more useful

The process of ____ is used to overcome the degradation of the S/N ratio.

• suppression
• companding
• regeneration
• equalization

Group 3 fax uses what type of modulation?

• QAM
• PSK
• Vestigial sideband
• FM

What portion of the TV signal is used to synchronize the video information on the recording tape?

• the vertical sync
• the horizontal sync
• the vertical deflection coil
• the raster line