ON PASSAGE - ROUTINE COMMUNCATIONS
1. Selecting Correct VHF channel for local shore authorities.
i) Know your correct location.
ii) See the back of each part of ALRS Volume - 6, so as the know the correct part of the
ALRS volume 6.
iii) After selecting the correct part, refer the volume for the country in which you are. The
order of countries in the volume will be in the alphabetical wise.
iv) After finding your country, refer to the port in which you are. The port details will be
under your country's section.
v) Select Appropriate Channel/ Frequency for that particular port.
Note - 1) Refering to the correct part of the ALRS Volume - 6 is very important.
2. Adjusting transmitter power output on VHF
We adjust transmitter power output depending upon the range of communication so as to minimise the interference caused by/ caused to other stations.
For Greater distance we use HIGH Power
For Smaller distance we use LOW Power.
Note - For onboard communication we preferably use LOW Power.
3. Setting Volume and Squelch
4. Adjusting Dimmer/ Contrast Control on VHF
We will use Dimmer/ Contrast Control when the intensity of the light of the VHF display is distracting us in Navigation.
Note - It is not necessay thay we use dimmer/ contrast control during night time only.
5. Demonstration of Dual Watch
Dual watch means keeping watch on 2 channels simultaneously.
We preferably keep dual watch on Pilot's Channel/ Port Control AND CHANNEL 16.
i) Enter the channel with whom you want to keep Dual Watch. (Except Ch 16)
ii) Press Scan to enter Dual Watch Mode/ to remove Dual Watch Mode.
Note - While keeping Dual Watch One Channel has to be 16.
6. Selecting International Distress Channel on VHF R/T
7. Making Routine Ship to Ship Call using VHF or MF DSC.
i) Refer to International Telecommunication Union (ITU) List 5 (List of ship stations to find the MMSI number of the given
ship's name. (Note - Ship Names are arranged in alphabetical order)
ii) Select "Main Menu" in VHF/MF DSC controller.
iii) Select "TX-CALL".
iv) Select "Individual".
v) Enter the MMSI number of the ship to call.
vi) State appropriate R/T frequencies (2048 KHz for MF/ Ch. 06 for VHF).
vii) Press "Call".
8. Adjusting Power Output of MF/HF Transmitter
Max Power (HF) - 1500 Watts
Max Power (MF) - 400 Watts
Medium Power (MF) - 200 Watts
Low Power (MF) - 100 Watts
We use different transmitter power output depending upon the distance between us and the target station.
Larger the distance, Higher the power output used.
9. Selecting Correct HF R/T ITU Channel with a given coast station for a given position and time
i) Know the correct location of the given Coast Station.
ii) See the back of each part of ALRS Volume - 1, so as the know the correct part of the ALRS volume 1.
iii) After selecting the correct part, refer the volume's index for the country in which the Coast Station is. The order of countries in
the volume will be in the alphabetical wise.
iv) After finding the country, refer to the port in which the station is. The port details will be under your country's section.
v) Swith over to the given page as found in the index.
vi) Select Appropriate HF Frequency for that particular station depending upon the LMT and the availability of the frequency at the
given time for that station.
Frequency Band in MHz
Distance Covered Daylight Coverage
800 - 1200
800 - 1000
1200 - 1600
1000 - 1200
1600 - 2000
1200 - 2000
2000 - 2500
2000 - 2500
10. Adjusting MF/ HF Transreceiver for Reception of Live Signal.
i) Press RX.
ii) Enter frequency.
iii) Apply Tune Rate to listen the frequency clearly.
iv) If signal starts fading use Automatic Gain Control (AGC) for proper reception of the frequency.
v) Use Sensitivity Control or R/X Gain Control for proper reception of the frequency.
vi) Adjust Volume as required.
11. Sending Routine text message to a given destination on INMARSAT-C.
i) Prepare message in File Menu.
ii) Go to Transmit Menu.
iii) Select Routine Priority.
iv) Select Telex Number from address book.
v) Select CES of the country.
Note - We can choose any CES while sending Routine message only.