CTS General 4 — Questions and Answers
Question 1: A client reports that a newly installed projector displays a 'no signal' message even though the source device is connected via HDMI. What is the FIRST troubleshooting step?
- Replace the HDMI cable immediately
- Verify the projector input selection matches the connected port (Correct answer)
- Restart the source device and projector simultaneously
- Check the projector lamp life hours
Correct answer: Verify the projector input selection matches the connected port
Confirming the input source selection on the projector matches the physical HDMI port in use is the quickest first diagnostic step.
Question 2: Which cable type is BEST suited for transmitting both uncompressed HD video and audio over distances up to 100 meters in a professional AV installation?
- HDMI with a standard copper cable
- HDBaseT over Cat6 cable (Correct answer)
- DisplayPort over fiber
- Composite video with balanced audio
Correct answer: HDBaseT over Cat6 cable
HDBaseT extends uncompressed HD video, audio, control signals, and power over a single Cat5e/6 cable up to 100 meters.
Question 3: In a conference room with significant ambient noise, which microphone polar pattern is MOST appropriate for capturing a single presenter at a podium?
- Omnidirectional
- Figure-eight (bidirectional)
- Cardioid
- Hypercardioid (Correct answer)
Correct answer: Hypercardioid
A hypercardioid pattern has a narrower pickup angle than cardioid, providing better rejection of ambient room noise while focusing on the presenter.
Question 4: What does the term 'gain structure' refer to in an AV audio system?
- The physical mounting structure of gain amplifiers
- The optimized setting of each device's gain to maximize signal quality and minimize noise (Correct answer)
- The total wattage output of all amplifiers in a system
- The frequency response curve of the audio signal chain
Correct answer: The optimized setting of each device's gain to maximize signal quality and minimize noise
Gain structure is the practice of setting each component's input and output levels to maintain the best signal-to-noise ratio throughout the entire signal chain.
Question 5: A CTS professional is calculating the throw distance for a projector. The room is 30 feet deep and the image must be 10 feet wide. Which specification should be consulted?
- Lumens rating
- Contrast ratio
- Throw ratio (Correct answer)
- Keystone correction range
Correct answer: Throw ratio
Throw ratio (throw distance ÷ image width) determines the required projector placement distance for a desired image size.
Question 6: Which AVIXA standard defines the minimum and recommended video display levels for AV systems?
- ANSI/AVIXA 2M-2010 (Correct answer)
- ANSI/AVIXA 4OHMS
- IEEE 802.3
- EIA-861
Correct answer: ANSI/AVIXA 2M-2010
ANSI/AVIXA 2M-2010 (Audiovisual Systems Performance Verification) includes standardized criteria for display brightness and image quality.
Question 7: During an AV system commissioning, a technician notices a 60 Hz hum in the audio output. What is the MOST likely cause?
- Incorrect sample rate on the audio interface
- A ground loop between connected equipment (Correct answer)
- A damaged speaker cone
- Insufficient amplifier headroom
Correct answer: A ground loop between connected equipment
A 60 Hz hum in audio systems is a classic symptom of a ground loop, caused by multiple devices sharing different ground potentials.
CTS General 4
A client reports that a newly installed projector displays a 'no signal' message even though the source device is connected via HDMI.
What is the FIRST troubleshooting step?