In any private marine vessel, whether it is a humble sailing dinghy or a full-powered yacht, knowing your location is the single most important item considered for proper navigation. There are varieties of devices that can assist the seafarer with location positioning, aside from navigational sea charts, but one piece of equipment that no boat should be without is the marine depth sounder.
A depth sounder is a deceptively simple device: Sound, usually in the form of a high frequency pulse, or “ping”, is broadcasted to the bottom of a body of water and the returning echo is digitally calculated to indicate depth. For instance, if the distance to the bottom of a coral reef is needed, the ping is directed downward, “bounces” off the solid surface, and the returning echo arrives at the sensor at a certain time, thus calculating the distance from the transmitter to the bottom.
The ping involved is a concentrated beam of sound waves produced by a transmitting device known as a “transducer”. This is usually a submerged, small metal instrument installed either to the side of the boat hull or mounted directly beneath. This allows for a clean transmission of sound. The sound itself is of a frequency that is unique to the device used so there is no interference from natural or artificial sounds. The frequency is also tuned for seawater, which is denser than fresh water, and this type of depth analysis device is designed for sea vessels.
The receiver is also installed somewhere on the hull, or on a pole to the side of the hull. The receiver of a marine depth sounder is designed to detect the sound waves reflecting off of a solid object. The echo is then transformed into electrical signals, which can be sent via electrical wiring to the apparatus that actually does the calculation.
The device that receives the electrical signal is a marvel of modern computing technology. Older marine depth sounders were bulky and hard to read accurately for the nonprofessional. Now, however, virtually anyone can use the devices without formal training. If you can read a simple manual, then the depth sounder you choose to use will become a part of your instrumentation in no time.
The instrument calculates depth by deducing the time between “ping” and “echo”. The ping is sent downward, at the speed of sound, and is reflected, or “bounced”, off the solid bottom surface. The reflected sound, or “echo”, comes back at a slower speed and at a certain time depending on the depth of the water. This “time scale” is what the calculation device of a marine depth sounder uses to indicate depth.
Many of the newer depth sounders have water temperature and even water speed incorporated into their sensors. This is a boon to both angler and researchers as depth, temperature, and water flow can be catalogued constantly. Marine depth sounders are tools that will become more and more precise and easy to use, so that everyone with sea legs can enjoy the waves.
Welcome to Marine GPS For U, inside you will discover an amazing selection of low priced and excellent quality marine depth sounders.
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