Ukrainians Built a Jammer That Tells Russian Drones They're In Peru

The Lima jammer protected the port of Reni from drones—and from jamming skeptics

In August 2023, the Ukrainian defense ministry tasked the Night Watch electronic warfare team with a critical mission: defending the port of Reni from Russia’s Shahed drones.

Reni, one of the ports of the Danube River in southwestern Ukraine, is a vital backup to Ukraine’s main strategic port, Odesa. The 440-pound Shaheds threatened to throttle Ukraine’s grain exports—the backbone of its economy.

Night Watch’s Lima jammer was just the thing to protect the port. But actually defending Reni wasn’t the team’s only challenge. It also had to prove it was defending the port.

One of the team’s methods was also an inside joke. It branded its Lima jammer by programming it to tell Russian drones—and Ukrainian rivals—that they were in Peru, not in Ukraine.