Oleg Rogozovsky, a 1964 graduate of physical mechanics at LPI, could not find a job in his specialty in Kyiv. The patronymic - Abramovich - got in the way. Finally, he was lucky, he was allowed to drop an “anchor” in mailbox 153. At the physical mech, he was forced to learn something that was not what he wanted; in the box, he had to do something that was not taught to him. The new field of activity was described by the romantics as “a sparkling mixture of physics, electronics and maritime science”; physicists called it hydroacoustics. A book about a young specialist becoming a professional, expeditions, flight and sea tests, about colleagues, family and friends against the backdrop of life in Kyiv and the USSR in the 60s and 70s. Contains obscene language.