98J3 What are potential dangers of automatic transceiver switching in response to a dsc call?

A. Incorrectly formatted DSC calls from other vessels result in a warning in the DSC alarm screen but the vessel still might be switched to an illegal or improper outcome.

B. The transceiver may be switched out of the marine bands or the frequency may not match the requested priority or emission.

C. The automatic transceiver switching software always detects improper priorities, emissions & frequencies to ensure there is no danger.

D. The automatic transceiver switching feature always interrupting safe navigation of your own vessel and placing the unit on the GMDSS Distress, Urgency or Safety follow-on frequencies.

98J4 Which of these would not be a bad outcome of an Urgency dsc call to all vessels specifying an alternate telex frequency & emission that cause your transceiver to automatically switch?

A. The DSC controller decoded the contents of the DSC call and the requested frequency is not on the DUS table/placard but is in the marine band frequencies in the J2B emission.

B. The DSC controller decoded the contents of the DSC call and the requested frequency is on the DUS table/placard in the J3E emission.

C. The DSC controller decoded the contents of the DSC call and the requested frequency is on the DUS table/placard in the J2B emission.

D. The DSC controller decoded the contents of the DSC call and the requested frequency is not on the DUS table/placard, is not in the marine band or the other vessel requested a J3E emission.

98J5 An incoming Distress priority 16 MHz DSC call requesting J3E emission might automatically switch to what frequency?

A. 16420.0 MHz

B. 16696.5 kHz

C. 16420.0 kHz

D. 16804.5 kHz

98J6 An incoming DSC Distress alert on 8414.5 kHz will have what result?

A. The DSC controller will emit both an audible and visual alarm.

B. The particulars of the alert may be printed out.

C. The Distress information contained in the alert will be sent to the data directory.

D. All of these answers would typically occur.

Answers: 98J1 - D 98J2 - A 98J3 - B 98J4 - C 98J5 - C 98J6 - D

Section-j: mf-hf Equip. And Comms: Key Topic #99: Batteries:

99J1 What is the normal voltage of a single lead acid battery cell?

A. 1.5 volts

B. 2.5 volts

C. 2.1 volts

D. 1.2 volts

99J2 What is the normal specific gravity of a fully charged lead acid battery cell? What device is used to measuring the electrolyte of a lead acid battery?

A. 1.375 Voltmeter

B. 1.180 Voltmeter

C. 1.210 Hydrometer

D. 1.280 Hydrometer

99J3 What is a gel cell battery and how is it maintained & cared for?

A. Gel cell batteries are typically sealed; special charging rates and voltages may be required.

B. Gel cell batteries are lead acid with a solid electrolyte; each cell is checked with a voltmeter.

C. Gel cell batteries are NICAD with a solid electrolyte; each cell is checked with a voltmeter.

D. Gel cell batteries are have special liquid electrolytes; they are charged with the NICAD charging rates and voltages.

99J4 What will cause an individual battery cell to reverse polarity.

A. High discharge rates without allowing for a cool down period.

B. When discharging the battery string if a cell becomes weaker than the remaining cells, the discharge current will effectively charge the weaker cell in reverse polarity.

C. Insufficient charging which does not bring all of the cells up to full charge.

D. The charging circuits are connected in the correct polarity but all of the cells are equally charged.

99J5 What is the effect of temperature on the specific gravity of lead acid batteries?

A. Higher temperature results in a higher specific gravity reading.

B. Higher temperature results in a lower specific gravity reading.

C. Temperature has no effect on the specific gravity reading.

D. Lower temperature results in a lower specific gravity reading.

99J6 What would be an indication of a malfunction on a GMDSS station with a 24 VDC battery system?

A. All of these symptoms would indicate a potential battery charger malfunction.

B. After testing the station on battery power, a voltmeter reading of 30 volts for a brief period followed by a steady 26 volt reading.

C. A constant 30 volt reading on the GMDSS console voltmeter.

D. After testing the station on battery power, the ammeter reading indicates a high rate of charge that then declines.

Answers: 99J1 - C 99J2 - D 99J3 - A 99J4 - B 99J5 - B 99J6 - C