hˈaɪpoʊ wʌz ɐsˈaɪnd ɹᵻspˌɑːnsəbˈɪlᵻɾi fɔːɹ wˈɜːk ˌɔn dʒˌæpənˈiːz nˈeɪvi sˈɪstəmz, ænd ˈæftɚɹ ɐn ɐɡɹˈiːmənt wɪð ɔːstɹˈeɪliə, ðə juːnˈaɪɾᵻd kˈɪŋdəm ænd nˈɛðɜːləndz tə ʃˈɛɹ ðɪ ˈɛfɚt, wˈɜːkt wɪð kɹˈɪptoʊ ɡɹˈuːps bˈeɪst æt mˈɛlbɚn, hˈɑːŋ kˈɑːŋ ænd bætˈeɪviə.
HYPO was assigned responsibility for work on Japanese Navy systems, and after an agreement with Australia, the United Kingdom and Netherlands to share the effort, worked with crypto groups based at Melbourne, Hong Kong and Batavia.