FCC Commercial Radio case studies
FCC Commercial Radio · Put your knowledge to work in context.
The FCC Commercial Radio Operator License is a United States federal credential issued by the Federal Communications Commission for people who operate certain radio stations and transmitting equipment. It is distinct from the amateur (ham) radio service and from broadcast-station licensing; it is a personal operator authorization held by an individual, not a station authorization. The FCC Commercial Radio case studies are 5 cases and about 4,451 words.
1Two MF DSC Distress Alerts, No Voice Contact, Marginal Coast Guard Coverage
You are the only licensed operator on watch at a remotely sited public coast station on the Maine coast; the time is 0342 local. The MF DSC receiver monitoring 2187.5 kHz prints a distress alert: format distress, MMSI 316009887, position 44°11.6'N 068°40.2'W, nature 'fire/explosion', time 0340, telecommand 'no information'.
860 words, about 4 min2A MAYDAY for a Hydraulic Pump, a Real Medical Emergency on the Same Channel
You are the licensed operator at a small public coast station serving a working harbour. At 1128 a vessel hails your working channel: 'MAYDAY, MAYDAY, MAYDAY, [station], this is the fishing vessel North Star, we need immediate assistance.' You answer, and the skipper explains that the hydraulic steering pump seized, the boat is anchored in light winds two miles off the breakwater with four people aboard, nobody is hurt, and a mechanic has ordered a replacement part that should arrive on the 1400 tide.
897 words, about 4 min33:1 SWR on 2182 kHz After an Antenna Insulator Repair
After a rigger replaced a cracked ceramic insulator at the base of a ship's 10 m MF/HF whip and re-taped the connector where the coaxial feedline joins the antenna, the ship's 150 W MF/HF transmitter no longer matches its antenna. The installation uses a base-mounted automatic antenna coupler.
922 words, about 5 min4GMDSS Reserve Battery That Passes on Paper and Fails in a Cold Compartment
The GMDSS reserve source of energy on a 24 V DC vessel is a single lead-acid battery bank: 12 cells, nameplate 120 Ah at the 20-hour rate, installed in a compartment that reaches 0 °C in winter, now six years old. The ship's GMDSS documents require the reserve to carry all GMDSS loads for 6 hours, and the approved load figure in the manual is 14 A at 24 V.
936 words, about 5 min5Overdeviation on a Coastal Station's VHF Working Channel
A small marine public coast station operates a 50 W VHF base station licensed for 50 W output. Boaters in the harbour complain that whenever the coast station transmits on channel 22A their conversations on the neighbouring channel break up, and one reports hearing the coast station faintly two channels away.
836 words, about 4 min