He is also an active IOTA activator. Within the last seventeen years he was QRV from 38 islands located in 35 IOTA groups. His radio trips was described in the book "My Island Holidays with Radio" published in 2024. The second edition of it, revised and updated is planed for the second half of 2026.
With his radio he visited 16 DXCC entities using callsigns: 3W2JK, 3W4JK, 3W9C, 3W9JK, 5B/SP5APW, 9A/SP5APW, 9M2/SP5APW, 9W2/SP5APW, CE7/SP5APW, DL/SP5APW, DU1/SP5APW, DU9/SP5APW, ES8/SP5APW, FO/SP5APW, H84JK, KH0/SP5APW, OM/SP5APW, W4/SP5APW, W5/SP5APW, XU7AKC and XV9JK.
Jacek also participated in two multi-operator expeditions: S79C to Coëtivy Island AF-119 in 2015 and TX7N to Hiva Oa Island OC-027 in 2025.
Jacek is a member of PZK (PARU) and SPDXC.