"Design conscious but supremely functional- the new STC Deltaphone represents an entirely new approach to telephone design. A choice of restrained colours, lightweight handset, electronic tone caller with volume control, optional dial illumination, compactness... everything new! The STC Deltaphone is particularly suited for use in homes, hotels, reception lounges and 'front offices', where harmony of design, functional elegance and prestige are essential. As well as its superb modern appearance, fit to grace any expensive flat, the basic economies of space and effort give this new telephone utmost utility in offices and other business premises. High technical specifications match the trend-setting symmetry of this truly new telephone."



Advertising the Deltaphone: One of the first adverts for the Deltaphone was featured in the Summer 1965 Post Office Telecommunications Journal.

Here's a selection of magazine adverts which appeared in the Post Office Telecommunications Journal between 1965 and 1972.

Text as per Summer 1965 ad (above).


STC's Deltaphone advert (Feb 1965) in the Post Office Telecommunications Journal Spring 1965.

This is the only time most ordinary phones become interesting; when they ring. But we can show you a very out-of-the-ordinary telephone that will interest you - and everyone who sees it - at once. On sight. Even without ringing. A phone that is both entirely new in design and supremely functional.

Wouldn't you be interested to see such a phone? Even before you hear it ring? Especially as the Deltaphone doesn't ring at all; just warbles discreetly, at any volume you choose.



STC's Deltaphone advert in the Post Office Telecommunications Journal Spring 1966.

Her phone will never ring again.

Not the Deltaphone. It warbles instead, And that's only one feature of this revolutionary instrument. So compact and light is the Deltaphone, you can pick up the whole set with one hand. It's a technical masterpiece - entirely new in design - ideal for use wherever functional elegance and prestige are essential. Take a look at it. Then you'll see why it won a British Design Centre Award.


STC's Deltaphone advert in the Post Office Telecommunications Journal Autumn 1966.

Even in the dark, you can tell the new Deltaphone is revolutionary. Try picking it up with one hand. Easy. The compact body is only slightly wider than the dial - 4.3 inches (109 mm). And it's as lightweight as it is compact. At 4 ounces (120 gms), the handset - which rests neatly along the body - is less than half the weight of an ordinary handset. Listen when the phones start ringing. The Deltaphone doesn't. It warbles discreetly. At any volume level you choose. And, when it's silent, the Deltaphone still attracts attention. By its looks. Its functional design has earned an award from the Council of Industrial Design. Once you've studied its high technical specifications, seen the restrained colours in which it comes, and noted such features as optional dial illumination, you'll have your own awards to make. Sufficient to say now that the Deltaphone is ideal for reception areas, modern offices - wherever prestige is essential.

You can pick out the new Deltaphone with your eyes closed - Post Office Telecommunications Journal Spring 1967.

The Deltaphone can have a luminescent dial. So when the lights fail at the office, you can still see to 'phone. Or on bedside extensions at home you can dial without turning on the lights and waking the wife. Nobody gets disturbed when the Deltaphone rings either. Mainly because it doesn't ring. It just warbles at the volume you set. In fact the Deltaphone is a very sociable instrument. People like it because it's slim - at 4.3 inches it's only a fraction wider than the dial. And the 4-ounce handset is only half the weight of a conventional one. So it's twice as nice to hold. Add the Deltaphone's restrained colours, its elegant shape - and its exacting technical specification - and you have an irresistible telephone.


STC's Deltaphone glows in the dark... with pride - Post Office Telecommunications Journal Winter 1968.

STC's Deltaphone is pretty exciting, after all. And it does things other telephones don't. For instance, it can glow in the dark. There's an optional luminescent dial which lets you dial without turning the lights on. And nobody gets disturbed when the Deltaphone rings. Mainly because it doesn't ring. It just warbles- at the volume you set. In fact the Deltaphone is very sociable. People like it because it's slim-at 4.3 inches it's only a fraction wider than the dial. And the 4-ounce handset is only half the weight of a conventional one. So it's twice as nice to hold. Add the Deltaphone's restrained colours, it's elegant shape- and its exacting technical specification- and you have an irresistible telephone.


Some people get quite worked up when they have an STC Deltaphone -  Post Office Telecommunications Journal Winter 1969.

Every Deltaphone your subscriber rents means more profit for you. And Deltaphone has a modern shape and comes in colours to blend with any colour-scheme. That's why so many people want one. There is no extra outside plant investment and maintenance is easy. Let us help you make your fortune.


STC Subscriber Apparatus & Acoustic Division, New Southgate, London, N.11. Tel: 01-368 1234. Telex: 21917 


Our phone is your fortune -  Post Office Telecommunications Journal Winter 1971/2.

You can take any colour Deltaphone and turn it into gold. Deltaphone is sculptured on modern lines but fits in beautifully with any decor. That's why more and more people are asking for them. And with no extra outside plant investment-plus easy maintenance-there's also extra income in it for you.


STC Subscriber Apparatus & Acoustic Division, New Southgate, London, N.11. Tel: 01-368 1234. Telex: 21917 


As good as gold -  Post Office Telecommunications Journal Autumn 1972.