RCDD-001

RCDD-001 practice questions, page 2 of 15, with answer review and explanations.

Question 6

Two sinusoidal signals have the same amplitude (A) and the same frequency (f). They differ in phase by 180 degrees. If these two signals are added together, the result is a sinusoidal signal having an amplitude of:

  1. Zero
  2. 0.707A and a frequency of f
  3. A and a frequency of 2f
  4. 2A and a frequency of f
  5. 2A and a frequency of 2f

Question 7

The signal at the input to a balanced twisted pair cable is 10 mW. The cable is 1000 feet long and has an attenuation of 1 dB per 100 feet. This cable is connected to the input of a receiver. The noise level at the input to the receiver is 1 microwatt. What is the signal-to-noise ratio (SNR) (dB) at the receiver input?

  1. 10 dB
  2. 30 dB
  3. 40 dB
  4. 60 dB
  5. 100 dB

Question 8

Time division multiplexing (TDM) systems are designed to transport ________ between end point systems.

  1. Only analog signals
  2. Only digital signals
  3. A mix of both analog and digital signals
  4. Both analog and digital signals, but only one type at a time

Question 9

The public telephone system is an example of a __________ system.

  1. Simplex
  2. Half-duplex
  3. Full-duplex
  4. Purely analog
  5. Purely digital

Question 10

A reasonable approximation for the signal speed in 100 ohm balanced twisted pair cable is __________, where c is the velocity of light in free space.

  1. 0.2 c
  2. 0.4 c
  3. 0.6 c
  4. 08 c
  5. 0.9 c