On 10 December a launch left Sadarghat for Bhola carrying fifteen people and, waiting for them at Kachchhapia ghat, a truck with roughly a tonne of tents, solar panels, generators, batteries, coils of feeder cable and antennas. Two and a half hours by trawler later, they waded ashore on Tarua, an uninhabited beach at the southern tip of Char Fasson where the Meghna meets the sea. For the next twelve days their address was a call sign: S21DX.
What amateur radio actually is
Amateur — “ham” — radio is a licensed hobby in which private individuals talk to each other across the world by radio, with no internet, no operator and no network in between. The pleasure is not that it works but that making it work is hard. A high-frequency signal from a Bangladeshi beach reaches Texas only if the antenna, the power, the time of day and the state of the ionosphere all cooperate; the operator who builds a station that achieves it has done something closer to science than to chatting. Every licensed operator carries a call sign issued under International Telecommunication Union rules. The prefix says the country: S21 is Bangladesh, so when the writer of the original account, S21R, keys his microphone, an astronaut on the space station would know where he is.
Islands On The Air
IOTA is a worldwide programme in which operators earn credit for contacting stations on islands. Bangladesh has run an IOTA expedition every year since 2009, and the regulator, BTRC, issues a special call sign — S21DX — that is valid for just seven days annually. Because it is so rare, hams on every continent wait all year to log a contact with it, which is why a dozen antennas rose on Tarua within hours of landing and why the team ran shifts through the night. The 2024 expedition was also a homecoming: the author flew in from Dallas with three suitcases of camping equipment, forty years after his last trip down the river by steamer.
How you get a licence in Bangladesh
Transmitting was illegal for private citizens for decades; the author built his first receiver in 1973 in class five and could only listen. The Bangladesh Amateur Radio League, founded under Saifuddahar Shahid (S21A), pushed for years to open the hobby; in 1992 a US-licensed exam was run in Dhaka with help from the Foundation for Amateur International Radio Service. Today BTRC holds an amateur radio examination every year. Pass it, meet the conditions, and you receive your own S21 call sign. It is one of the few technical licences in the country that a teenager can earn.
Why it still matters
When cyclones take down mobile towers, licensed hams are the people who can still pass messages. In a country whose coast floods every few years, a hobby that trains people to build a working radio station on a beach with solar power is not nostalgia. It is a skill in reserve.
