Astec

[1][2] Astec was founded in British Hong Kong in 1971[1] by Brian Christopher and Neal Stewart, as a producer of DC-to-DC converter hardware.

[5] Astec's converters were initially purchased chiefly by manufacturers of electronic calculators, a market which was experiencing meteoric growth in the early 1970s.

[6][8] Helped by these lucrative contracts, Astec grew to become the world's largest manufacturer of power supply units by 1985, taking the top spot from Lambda Electronics.

[9] Birmingham Sound Reproducers (BSR), a British manufacturer of home audio equipment, purchased a controlling 53.6-percent stake in the company in May 1980.

[12][13] By 1984, BSR began shedding its home audio assets as computer power supplies became the company's core business.

Power supply unit from an Osborne 1 portable computer manufactured by Astec