After the death of Howard Anthony in 1954, Heath was bought by Daystrom Company, a management holding company that also owned several other electronics companies. Daystrom was absorbed by oilfield service company Schlumberger Limited in 1962, and the Daystrom/Schlumberger days were Heathkit's most successful. Those years saw some "firsts" in the general consumer market. The early 1960s saw the introduction of the AA-100 integrated amplifier. The early 1970s saw Heath introduce the AJ-1510, an FM tuner using digital synthesis, the GC-1005 digital clock, and the GR-2000 color television set. In 1974, Heathkit started "Heathkit Educational Systems", which expanded their manuals into general electronics and computer training materials. Heathkit also expanded their expertise into digital and, eventually, computerized equipment, producing among other things digital clocks and weather stations with the new technology.