Authorities believe they have found the culprit that was causing static for T-Mobile US Inc. customers in southern Brooklyn: an energy-sucking, interference-spewing cryptocurrency miner tucked away in a home.

T-Mobile signage
Bloomberg News

Agents for the Federal Communications Commission used direction-finding devices to locate the offending equipment in a home in zip code 11229, an area that includes Sheepshead Bay. On Thursday they sent a notice to a resident telling him to shut off his Antminer s5 Bitcoin Miner, or risk fines and seizure of the device.

“The device was generating spurious emissions on frequencies assigned to T-Mobile’s broadband network and causing harmful interference,” David Dombrowski of the FCC’s enforcement bureau, said in the notice. “Are you still actively using the device?”

The increasingly difficult computations needed to create new blockchains -- the encrypted digital ledgers that underpin cryptocurrencies -- require powerful computers.

That means bitcoin mining consumes electricity on a large scale, and operators often choose to work near cheap electricity sources -- which wouldn’t seem to include a home in Brooklyn.

For instance, one entrepreneur put computers inside a cargo container in a dilapidated Soviet-era tractor factory in the nation of Georgia. That site made sense for running servers 24 hours a day because it has access to cheap electricity generated by water flowing from the nearby Caucasus Mountains.

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