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Information on Digital Calling Service

Digital calling service refers to a system of sending pre-determined digital messages through medium frequency, high frequency and very high frequency. The digital calling service was used a replacement for older warning methods. The main reason for this is that DCS uses a signal system which is pretty much stable. Its range is also a bit longer than that of analog signals. It has a significantly longer range by almost twenty five percent and is carried much faster as well. Tis makes it easier to rescue hips in critical situations.

The digital calling service senders are equipped with the ability to identify the maritime mobile service and is normally connected to the ship’s GPS. This allow the apparatus o identify the signal which is being sent, the time and the date of the signal as well. This comes in especially handy when there is a distress warning which is imminent in the near future.

Most often ships make use of different high frequency or medium frequency receivers. However in case of a very high frequency signal the digital calling service has its own dedicated receiver. For users who receive these signals the controller normally compromises of a single unit. These devices are designed to receive multiple distress signals.

What happens during the receiving of a distress signal?

When the digital calling service sends a distress signal it will ensure that’s the ships mms number is included. It will even provide the coordinates if those are available plus information about the channel to receive these radiographic transmissions. Distress signals are sent as a single frequency or as a multiply frequency request. The DCS would wait for a four minute interval is no acknowledgement is made for the distress signal before sending another one. The distress signals can be sent for five times at least. Multiple signals should only be sent in case of the ships batteries becoming wet in a little while.

The distress calls can be both designated and non-designated. The following designations could be received which include

  • In case of abandoning ship
  • In case of a fire or explosion on the ship
  • Flooding
  • Collision between a ship or any other object
  • In case of grounding and listing
  • A piracy attack
  • Or man overboard

False distress alerts are avoided with the help of protective covers. The cover are spring loaded it’s necessary to sue both hands when sending signals. Any coast station which receives a distress signal should immediately send an acknowledgement. The ships which are beyond reach yet receive a distress signal are supposed to relay the signal on land as immediately as possible.

There are certain high quality devices on ships which can easily send the distress signals. These devices can even send telephonic alerts as well. For recreational vessels these devices are not a necessity and they can make use of any D quality devices to send a distress signal at different frequencies.