What is a common occurrence when voice-testing an SSB aboard a boat?

Voltage panel indicator lamps may glow with each syllable.

The key word here is "boat." Smaller ships used for recreation (e.g., sailing, diving, sport fishing, fishing, water skiing) are not required to have radio stations installed but they may be so equipped by choice.

Generally, unlike on commercial vessels, there is far less protection of electrical systems from electromagnetic emissions, and the transmitted energy affects surrounding electronic instruments. Even small fluorescent tubes may glow during transmissions.

For marine SSB, the greater the MHz, the farther the signal will carry. For example, a 2 MHz may carry from 200 to 400 miles, while 22 MHz may extend from 2,200 to 4,000 miles. Thus, the selection of frequency bands may affect surrounding electronics differently.

For more information please see:

Power & Motoryacht site for The Skinny on SSB

Practical Sailor site for Conjuring Up Some SSB Magic

Latitude 38 site for Idiot's Guide to Marine SSB

FCC site for Ship Radio Stations (useful overall info)

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What might contribute to apparent low voltage on marine SSB transmitting?

Blown black negative fuse.

The SSB unit may not receive adequate current if it is drawing power from an alternative connection due to not functioning black negative fuse someplace within the electrical system.

The alternative connections tend to have a far greater resistance, so less current is delivered. The negative supplies energy and the positive returns to the source.

See WikiHow for the article "Identifying Positive & Negative Wires: Colors & Power Types"

Useful is Google's "Marine Electrical Checklist."

For more information, please see J.D. Power site, for the article How to Tell if a Car Fuse is Blown?

Also, please see National Library of Medicine, well illustrated article on Checking and replacing fuses

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What type of wire connects an SSB automatic tuner to an insulated backstay?

GTO-15 high-voltage cable.

This well-insulated copper wire is very flexible stranded twisted, and can be used in many systems.

The GTO stands for Gas Tube and Oil. It can carry a high voltage of up to 15,000 volts (thus GTO-15 kilovolts) and is preferred for neon sign installations.

It carries the 14AWG rating. See The Engineering ToolBox, for the AWG - American Wire Gauge Current Ratings.

For an example of the wire, please see Amazon, product Ancor Marine Grade Electrical GTO15 High Voltage Cable

For information about the insulated backstay, please see Wikipedia's article on Backstay insulator

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Which of the following statements concerning SITOR communications is true?

ARQ message transmissions are made in data groups consisting of three-character blocks.

For ARQ details, please see Geeks for Geeks site, for the well-illustrated article What is ARQ (Automatic Repeat Request)?

Also, see Wikipedia's article Automatic repeat request

SITOR (SImplex Teletype Over Radio) is a system for sending text messages. It was an improvement on the old RTTY radio teletype. This mode has error correction through the use of the automatic repeat request (ARQ). If error noticed, retransmission is requested.

For more info, please see Wikipedia's article on SITOR

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The sequence ARQ, FEC, SFEC best corresponds to which of the following sequences?

Two way communications, one-way communications to all stations, one-way communications to a single station.

ARQ --> Two way communications
FEC --> One-way communications to all stations
SFEC-> One-way communications to a single station

See Wikipedia's article on Automatic repeat request

See the TechTarget site for the article forward error correction (FEC), and the Tutorials Point site for the article Forward Error Correction (FEC)

For more information, please see My Sea Time site, for the article Where Does NBDP Fit in GMDSS and How to Use It ?

Also, see a comprehensive pdf document from the Crypto Museum site, titled Manual of Transmission Methods Reference Document, from Rohdes & Schwarz.

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Which of the following statements concerning SITOR communications is true?

Two-way communication with the coast radio station using FEC is not necessary to be able to receive the broadcasts.

As this is a texting service over radio, the receipt is not dependent on the two-way exchange. An example would be a marine weather report.

SITOR (SImplex Teletype Over Radio) is a system for sending text messages. It was an improvement on the old RTTY radio teletype. This mode has error correction through the use of the automatic repeat request (ARQ). If error noticed, retransmission is requested.

For more info, please see Wikipedia's article on SITOR

Also, for comprehensive details, please see the pdf document, Radio Navigational Aids, Publication 117 2005, published by the National Geospatial Intelligence Agency. Use CTRL-F and search for "SITOR"

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