CBT CBT Signal Processing & Distribution 1 — Questions and Answers
Question 1: What does SDI stand for in broadcast signal distribution?
- Serial Digital Interface (Correct answer)
- Standard Digital Input
- Synchronous Data Integration
- Signal Distribution Infrastructure
Correct answer: Serial Digital Interface
SDI (Serial Digital Interface) is a family of digital video interfaces used in professional broadcast to carry uncompressed digital video over coaxial cable.
Question 2: Which type of filter is used to remove frequencies above a specified cutoff frequency in a broadcast signal chain?
- High-pass filter
- Band-pass filter
- Low-pass filter (Correct answer)
- Notch filter
Correct answer: Low-pass filter
A low-pass filter allows frequencies below the cutoff to pass while attenuating higher frequencies, commonly used to limit bandwidth in broadcast audio and video chains.
Question 3: What is the purpose of a distribution amplifier (DA) in a broadcast facility?
- To encode video to compressed format
- To split and amplify a signal for multiple destinations without degradation (Correct answer)
- To convert analog signals to digital
- To synchronize genlock across all equipment
Correct answer: To split and amplify a signal for multiple destinations without degradation
A distribution amplifier splits one input signal into multiple identical outputs while maintaining proper impedance and signal level to prevent degradation.
Question 4: What impedance is standard for coaxial cables used in professional broadcast video?
- 50 ohms
- 75 ohms (Correct answer)
- 110 ohms
- 300 ohms
Correct answer: 75 ohms
75-ohm coaxial cable is the standard for professional broadcast video, balancing cable loss and power handling characteristics for video frequencies.
Question 5: In digital broadcasting, what is the function of a multiplexer (MUX)?
- To reduce signal noise
- To combine multiple signals onto a single transmission path (Correct answer)
- To convert HDMI to SDI
- To measure signal loudness
Correct answer: To combine multiple signals onto a single transmission path
A multiplexer combines multiple signals—such as video, audio, and data streams—into a single composite signal for efficient transmission over one channel.
Question 6: What is 'genlock' in broadcast signal processing?
- A digital encryption standard for broadcast content
- Synchronizing a video signal's timing to an external reference signal (Correct answer)
- A method of locking audio levels to video frames
- A type of error correction used in ATSC transmission
Correct answer: Synchronizing a video signal's timing to an external reference signal
Genlock synchronizes the timing of a video signal's sync pulses to an external house sync or black-burst reference, ensuring all sources in a facility are phase-aligned.
CBT CBT Signal Processing & Distribution 1
What does SDI stand for in broadcast signal distribution?