Trimphones

Trimphones are a model of telephone that were designed in the UK in the late 1960s. It was considered a more fashionable alternative to the standard telephones available from Post Office Telephones. The name 'trimphone' is an acronym which stands for Tone Ring Illuminator Model, which refers to the, at the time, innovative electronic ringer and illuminated dial.

The trimphone was invented by Martyn Rowlands for Standard Telephones and Cables. The initial idea originated in 1959 for a new, luxury telephone to add to the Post Office's range. Near the end of 1963 the Post Office chose Martyn Rowlands' design, although it had considered others. Then in 1964 the General Post Office placed the contract for 10,000 units.

In June 1991 the United Kingdom Atomic Energy Authority was fined £3,000 by Wantage Magistrates Court for accumulating radioactive waste, due to having collected several thousand Trimphone luminous dials in a skip! This was due to the luminous dial or betalight being mildly radioactive as it contained tritium. This later caused some concern about safety.

Even though the later model did not feature the original, light up dial, it was continued to be known as the Trimphone. This caused division amongst consumers regarding its aesthetic merits. Some models needed rewiring in order to connect to the UK public phone network.