Information Is Available On Three New Doppler Speed Logs By Raytheon
Literature is now available describing three new Doppler speed logs that use b o t t o m - r e f l e c t ed sound to provide accurate speed data from 0.01 knot to 40 knots, from Raytheon Marine Company.
The Raytheon Doppler systems track the bottom to depths of 1,000 feet using acoustic beams directed ahead, astern, and to each side of the vessel. In deeper water, the system automatically shifts from bottom-tracking to watermass-tracking. In addition to calculating speed, the Raytheon Doppler speed logs also provide a digital depth display to a maximum of 1,000 feet and can be read in feet, fathoms, or meters. The model DSL-250, simplest in the Raytheon line, is a singleaxis, dual-beam system designed for providing continuous accurate speed and depth resolution in the ship's f o r e / a f t axis.
In the "normal" operating mode, at speeds less than 9.99 knots, speed is displayed in hundredths of a knot. This ensures that the system will sense movement of as little as one foot per minute when approaching anchorage, moorings, or berths. Other features include an adjustable depth alarm, builtin self-test circuitry, and a mechanical distance-run log.
The model DSL-350 is a dualaxis, dual-beam system for selectable resolution of the ship's f o r e / a f t and p o r t / s t a r b o a rd speed. The p o r t / s t a r b o a r d or athwartships speed feature is especially useful in determining set and drift from the steered course. The model DSN-450 is a dualaxis, four-beam sonar navigator that provides continuous, simultaneous readout of the fore/aft and athwartships speed.
On all three models, data is processed for digital display on an easily read 11-inch by 14-inch bridge display/control unit and for input to radars, other shipboard electronic equipment, and i n t e g r a t e d navigation systems. Weatherproof digital and analog repeater displays are also available for use in exposed locations.
Additional i n f o r m a t i o n and complete specifications can be obtained by w r i t i n g to Stanley Clark, Raytheon Marine Company, 676 Island Pond Road, Manchester, N.H. 03103.