The General Post Office introduced the 746 telephone in 1967, replacing the 706. The 746 was a refinement of the earlier model, the biggest external change was to the cradle for the receiver which could double as a handle to carry the telephone. So, you could walk around while on a call and try and look cool.
Internally, the 746 had the regulator, which had been optional on the 706, built into the circuit board. The regulator could be used to vary the current flowing into the receiver and transmitter of the telephone as telephone lines too close to an exchange sometimes had trouble with the current on the line being too high.
The 746 remained in production for a long time, some were later modified to use the BT New Plan plug (the type still used today). These were known as the 8746 telephone and can still be used now with a supported line (though this will soon change).
I have three 746s in my collection: red, brown and topaz yellow.
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| Red phone |
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| Topaz yellow phone |
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| Black 706 (left) and 746 (right), showing the external difference |
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| Brown telephone |
