SBCA Installation Practices & Standards 5 — Questions and Answers
Question 1: What is the correct polarity of DC voltage applied over coax to power an LNB and select vertical polarization on a linear polarization system?
- 18V DC
- 13V DC (Correct answer)
- 0V DC
- 22V DC
Correct answer: 13V DC
13V DC applied over the coaxial cable selects vertical polarization on a linear LNB, while 18V selects horizontal polarization.
Question 2: When installing a satellite dish in a high-wind coastal area, which mounting configuration provides the greatest structural stability?
- J-mount on fascia board
- Chimney strap mount
- Ground-mounted concrete base with embedded pole (Correct answer)
- Non-penetrating roof mount with sandbags
Correct answer: Ground-mounted concrete base with embedded pole
A concrete-embedded ground mount provides the most rigid, wind-resistant foundation and is preferred in high-wind or coastal environments.
Question 3: According to FCC regulations, who is responsible for ensuring that a satellite receiving system does not cause interference to other users?
- The satellite operator
- The equipment manufacturer
- The installation technician and system owner (Correct answer)
- The local municipality
Correct answer: The installation technician and system owner
FCC Part 25 places responsibility on the licensee/system owner and, by extension, the installation technician to ensure the system operates within regulatory parameters.
Question 4: What is the maximum distance a ground rod electrode can be from the building entry point for the grounding conductor to remain compliant under NEC 810?
- The conductor must be as short and direct as possible with no stated maximum distance (Correct answer)
- 5 feet
- 10 feet
- 25 feet
Correct answer: The conductor must be as short and direct as possible with no stated maximum distance
NEC 810 requires that the grounding conductor be run as short and straight as practicable, but does not specify a maximum distance — minimizing conductor length is the goal.
Question 5: A customer reports intermittent satellite signal loss during rain. The dish alignment was verified to be correct. What is the most likely cause?
- Rain fade affecting the satellite uplink or the signal path (Correct answer)
- Receiver firmware bug
- LNB overheating
- Ground loop interference
Correct answer: Rain fade affecting the satellite uplink or the signal path
Rain fade occurs when precipitation absorbs and scatters microwave signals in the path between the satellite and the dish, causing signal attenuation.
Question 6: When using a cable stripper to prepare RG-6 for an F-connector, what portion of the cable dielectric (foam insulation) should be exposed?
- 1/8 inch
- 3/8 inch (Correct answer)
- 1/2 inch
- 1 inch
Correct answer: 3/8 inch
Proper RG-6 preparation exposes approximately 3/8 inch of center conductor and dielectric to correctly seat inside most compression or crimp F-connectors.
Question 7: Which SBCA installation standard addresses the requirement for a technician to verify 'clear line of sight' before finalizing a dish mounting location?
- SBCA STD-0101 (Correct answer)
- SBCA STD-0202
- NEC Article 810.15
- TIA-568
Correct answer: SBCA STD-0101
SBCA STD-0101 covers residential satellite system installation standards, including the requirement to confirm unobstructed line of sight to the satellite arc.
SBCA Installation Practices & Standards 5
What is the correct polarity of DC voltage applied over coax to power an LNB and select vertical polarization on a linear polarization system?