Private branch exchange

This Private Branch Exchange (PBX) or switchboard was used in Buckingham Palace to connect both internal and external calls. It was installed in a room off the Court Post Office in 1930 and was in use up until the late 1960s.

Made by ATM, originally the PBX was designed to have two stations, each for a male GPO telephonist. At night, the switchboard would be operated by one male telephonist only. These staff accompanied the Royal Family between residences, leaving the switchboard in the hands of relief GPO telephonists.

The operator would plug and unplug patch cords to establish connections for callers. When a handset was lifted within the Palace, it would light up a 'pearl'. The operator then plugged into the corresponding jack to check to whom they wished to speak. A secret password needed to be issued before any caller could be connected directly with Royalty. The operator used the speak keys on the console to talk and rang extensions using the ring keys. Calls were connected through a second cord. When the receiver was placed down, the light would go out and the operator would unplug the cords.

This switchboard was installed in 1930 after The Royal Household experienced 'the undesirable intimacy between the operators and the Household servants with its consequent back-stairs gossip, listening-in, and other abuses'. This new type of switchboard was said to 'prevent ‘listening-in’', unlike its predecessor. The Royal Household had just reverted to using GPO staff to operate their switchboards, having directly employed telephonists through the 1920s.

Edward VIII however did not trust it to handle his personal calls and in 1936 arranged for 'a small extra switchboard, with a private line to The Fort to handle my personal calls'. Fort Belvedere in Windsor Great Park was Wallis Simpson's home. With permission from the Home Secretary, the King's telephone calls were 'intercepted' by MI5 from 5 December 1937. That was done through the telephone junction box in Green Park, rather than through this switchboard.

After the Second World War the switchboard was extended with GEC equipment to have a third station. It may have been at this time, or slightly after, that it was modified for use with the new, lightweight headset No 1 (introduced 1958).

We know one switchboard operator who worked on this machine, Leo Baker. Born in 1897 in Bethnal Green, Leo began as a relief telephonist on the previous switchboard before securing a permanent position. He became Chief Telephone Officer and Chair of Royal Household Social Club in the 1940s until at least 1960 and is reported as dancing with the Queen at the Club's 1954 Christmas Ball.
The current switchboard's set up reflects the workings of the Palace as it was around the late 1960s. Internal extensions include Household staff and royalty. Both Queen Elizabeth II and Prince Philip's bedrooms have extensions - any which connected directly to HM The Queen are coloured red.

External direct lines include royal residences such as Clarence House, where HRH Queen Elizabeth the Queen Mother and Princess Margaret lived, government buildings and individuals such as the Prime Minister, Whitehall, Metropolitan Police Inspectors, and military officers.