Trans-Oceanic

The Trans-Oceanic (abbreviated T/O) was the name given to a series of portable radios produced from 1942 to 1981 by Zenith Radio. They were characterised by their heavy-duty, high-quality construction and their performance as shortwave receivers.

Zenith's founder, Commander Eugene F. McDonald, was a great admirer of advanced technological development and believed that his company's products should include the latest, most practical advances in a well-built product that continued to enhance the company's reputation. Of the many products of Zenith Radio, the 'Trans-Oceanic' series of portable radios were amongst the most famous.

McDonald was a keen yachtsman and outdoorsman and wished for a portable radio that would provide entertainment broadcasts as well as being able to tune into weather, marine and international shortwave stations too. He asked his company's engineers to develop prototypes to meet his criteria and by 1940 they had concept sets that were ready for production.

The Zenith 'T/O' began life in 1942 as the Model 7G605 'Trans-ocean Clipper'. Priced at $75, it was released in January but ceased production in April as Zenith shifted their production to war-related equipment. During this short production run, some 35,000 units were produced and sales data showed that many were sold to customers in the 'above average' income group. However, many also found their way into various theatres of war and in to the hands of appreciative servicemen—demand for a resumption of production at war's end was kept high.

The T/O was a dual-powered radio receiver; it could operate from electrical service AC or DC and via a pair of "A" and "B" dry cell batteries for portability. The batteries are obsolete but the early T/O models live on either due to the ability to use AC line or a battery made of modern cells (6 Ds for the "A" power and 10 9 volt transistor batteries for "B") or an inverter. Zenith used a selenium rectifier of later versions of the T/O, replacing rectifier tubes used on the earlier models. Inserting the power plug into a socket on the chassis or the side of the radio (depending on model) switched the T/O to battery operation.

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