Selective Calling System Saves Time For Oceangoing Tankers And River Vessels

A new selective calling system is helping AMOCO solve the problem of putting marine radiotelephone calls through promptly to its fleet of vessels scattered around the world.

On the inland waterways, barge owners are using the same system to dial calls directly to their fleets of towboats without voice monitoring.

At present, 12 oceangoing tankers in the AMOCO fleet are equipped with Lorain Encoders and Decoders, permitting selective automatic communications. Each of the 12 tankers can be called without use of voice calling and without the use of voice monitoring, much in the same way that you would dial a telephone call. A Lorain Selective Encoder and Decoder with six-channel search is installed at Station WSY, Lorain, Ohio, which in turn is connected to the AMOCO home office by a dedicated telephone circuit.

Each vessel is assigned its own five-digit calling code. For example, the Amoco Baltimore has the code 15142. When the company wants to contact the Amoco Baltimore off the African coast, the operator sets the code 15142 on the five thumbwheel switches of the Lorain Encoder. He then selects the correct frequency for the location of the vessel on the single sideband radio and presses the "transmit" button on the Encoder. The correct five-digit code is automatically transmitted in the proper sequence to the vessel.

On the Amoco Baltimore, the Lorain Selective Decoder is constantly searching six channels for a tone sequence representing the code 15142. The first tone stops the search until the tone sequence is identified. The search, and identification of the five digits, requires approximately two seconds.

Upon identification of the correct code by the Decoder on the Amoco Baltimore, an audible two-second signal is sounded and the appropriate channel indicator pushbutton (one of six) is illuminated. This identifies the calling frequency or station. The radio operator then selects the indicated frequency on the single sideband radio and answers the call.

AMOCO is able to save valuable time on its daily position report calls and other business with its fleet. Each call is placed by merely setting up the code and pushing the transmit button.

The radio operators also save time, and the radio can be turned down without missing an incoming call. No voice monitoring is necessary since each call is signaled audibly and also visually displayed on the vessel's Call Indicator.

This indication remains until canceled by the operator. Up to six calls can be stored on the "Call Indicator" until the pushbuttons cancel them.

Time can be devoted to navigation and other work, secure in the knowledge that the Lorain Decoder is doing the listening for the radio operator.

The best testimonial a user can make of a system is to make repeated purchases. AMOCO has done just that with 12 ships encoder/ decoder equipped, or on order, and more to come.

How do the barge lines feel about this new communications systems? "Based on present results from our encoder/decoder system," said one company spokesman, "we estimate that savings resulting from the ease of picking up new cargo en route should help us pay for the system in a matter of months. The pilothouse remains quiet and the crew is no longer bothered by radio chatter." Comments from the towboat captains have been favorable. The Lorain decoders have provided dependable communications in the same manner as an office telephone . . . when the signal sounds and a channel indicator light comes on. there is a call for the vessel.

In the words of one captain, "Tt's just like having a telephone in the pilothouse. When it rings, it's for you." The system operates from 117 volts AC 50/fi0 cycles or 13.6 volts DC. Power consumption is 30 watts. Solid-state modules assure dependable performance. The overall cost of the equipment depends upon specifications.

Some of the major barge lines using the Lorain encoder/decoder system fleet-wide are the Ohio River Company, Valley Line, and Wisconsin Barge Line.

Tack Cain, executive vice president, and Bill Taylor, sales manager, are optimistic about the future of the new automatic dialing system. Public correspondence stations on the inland waterways also have praise for the encoder/ decoder system. Offshore dredging rigs utilize the Lorain 'System as well.

Lorain Electronics Corporation has been a leader in the marine communications field since 1928, with headquarters at 2307 Leavitt Road, Lorain, Ohio 44052.

Other stories from February 1974 issue


Maritime Reporter

First published in 1881 Maritime Reporter is the world's largest audited circulation publication serving the global maritime industry.