Telephone exchange for use by blind operators, made by Imperial College and the RNIB, London,1977. Consisting of standard PABX7 switchboard plus special interface unit giving the operator guidance as to the state of the switchboard by means of synthesised speech, plus receiver and metal connector.

Telephone exchange for use by blind operators, made by Imperial College and the RNIB, London,1977. Consisting of standard PABX7 switchboard plus special interface unit giving the operator guidance as to the state of the switchboard by means of synthesised speech, plus receiver and metal connector.

In 1977, a project was begun at Imperial College, in partnership with the Royal National Institute for the Blind, to develop an interface unit that would allow blind telephone operators to use modern telephone exchanges. Previously, blind operators had relied on touch, with the standard flashing lights of a telephone exchange unit being replaced with pins that would protrude to indicate different functions. However, this was proving inadequate for the levels of information being made available by telephone exchanges. A new interface unit was designed by Graeme Wood, a post-graduate student at Imperial College, which instead gave basic audio instructions to blind operators. This set was the pioneer equipment that was installed at the Royal National Institute for the Blind.