➀ Researchers at the University of Padova are developing low-cost underwater communication modems and transducers, aiming to make water acoustic communication more accessible. ➁ The SubSeaPulse modem, priced at a tenth of the market rate, is built on a Raspberry Pi base with additional sound card hardware and a front end. ➂ The team is also working on a cost-effective transducer, reducing the price from over $2000 to around $400, using a modified device typically used for listening to marine mammals.