radio-frequency
(3)
Alex Wulff
From high-school science fairs and campus walkie-talkie tests to a New York defense startup, Alex Wulff has spent a decade making invisible signals legible - and low-cost radio hardware useful in the field.
Nine Fives
Nine Fives builds modern radio-frequency (RF) test equipment for manufacturers of wireless devices in cellphones, drones, and satellites. Founded by two former SpaceX engineers, the company replaces slow, driver-heavy legacy instruments with driverless, touchscreen, network-connected modules that share a single machine-readable API (REST and SCPI) and ship AI-readable documentation. The pitch: get RF test off the critical path and cut a hardware team's production-readiness timeline from months to minutes.
Distributed Spectrum
Distributed Spectrum builds AI-powered radio-frequency sensors and software that automatically detect, classify, and locate signals - drones, jammers, tactical radios, GPS spoofers - in real time. Founded by three Harvard engineers, the company packs commercial hardware and edge AI into sub-one-pound sensors that give soldiers and analysts persistent spectrum awareness without specialist RF expertise. It raised a $25M Series A in March 2025 and has fielded systems with US military branches and partners in Ukraine.