Mullard Limited was a British manufacturer of electronic components. The Mullard Radio Valve Co. Ltd. of Southfields, London, was founded in 1920 by Captain Stanley R. Mullard, who had previously designed valves for the Admiralty before becoming managing director of the Z Electric Lamp Co. The company soon moved to Hammersmith, London and then in 1923 to Balham, London. The head office in later years was Mullard House in Torrington Place, Bloomsbury, now part of University College London. In 1923, in order to meet the technical demands of the newly formed BBC, Mullard formed a partnership with the Dutch manufacturer Philips. The valves (US vacuum tube) produced in this period were named with the prefix PM, for Philips-Mullard, beginning with the PM3 and PM4 in 1926. Mullard finally sold all its shares to Philips in 1927. In 1928 the company introduced the first pentode valve to the British market. Mullard opened a new manufacturing plant at Mitcham, Surrey in 1929 and in late 1930s Mullard opened a new plant in Blackburn, Lancashire. By 1949 Mullard had produced a number of television sets, such as the MTS-521 and MTS-684 and in 1951 Mullard was producing the LSD series of photographic flash tubes. In the early 1980s, Mullard manufactured the SAA5050, some of the earliest teletext decoding modules made in the UK. In 1957 Philips-Mullard helped to set up the Mullard Radio Astronomy Observatory (MRAO) at the University of Cambridge. Philips continued to use the brand name "Mullard" in the UK until 1988. Mullard Research Laboratories in Redhill, Surrey then became Philips Research Laboratories. As of 2007, the Mullard brand has been revived by Sovtek, producing a variant of the ECC83 and EL34. The Z Electric Lamp Co. continued business into the 1970s operating from premises in Thornton Heath, south London, manufacturing lamps of specialised design but it closed due to the recession in the mid 1970s. Sovtek is a brand of vacuum tube owned by Mike Matthews's New Sensor Corporation and manufactured in Saratov, Russia. They are often used in guitar amplificationA box with a 'Mullard' valve for a radioTop of box : MULLARD / ELECTRONIC VALVE / Side of box; GAURANTEED ELECTRONIC / VALVE / MULLARD ( in a shield) : mullard radio valve co. ltd., london, mullard captain stanley, electronic equipment, moorabbin, bentleigh, cheltenham, early settlers