Group of electronics companies, of Sussex
1959 Company formed[1]
1960 C. T. Chapman (Reproducers) [2] and L. S. B. Components joined the group[3]
1963 Reslosound, microphone producers of Romford, was a member of the group[4]
1965 Public quotation of the shares; company was involved in electronics in the communications and environmental testing fields[5]
1973 Acquired Technical Indexes; acquired Hanbush from Amalgamated Industrials in exchange for shares which gave Amalgamated c.26 percent of the group[6].
1974 Amalgamated bid for the rest of the equity[7]
1978 Acquired Servotest[8]
1980 Amalgamated sold most of the shares it owned in the market[9]
1982 Derritron, of Middlesex, ran out of cash and called in the receiver[10]. The receiver aimed to sell the group by parts
By 1986 Derritron Electronics of Hastings, specialist in vibration testing, was part of the Derritron Group which was wholly-owned by Armstrong Equipment[11]