Frequency Electronics

Frequency Electronics has been making precision time and frequency hardware on Long Island since Martin Bloch founded it in August 1961. The company sits in an unglamorous but hard-to-replace position in the defense supply chain: almost nothing in modern military electronics works without a reference oscillator that holds its accuracy, and FEI has been building the space-qualified versions of those for over half a century. Its clocks flew on Voyager, and its rubidium atomic frequency standards are the timing heart of the GPS III satellite constellation, where an error of about one billionth of a second per day is what keeps the whole positioning system honest.

The company reports two segments. FEI-NY is the larger, and it contains three subsidiaries: FEI Government Systems, FEI Communications, and FEI-Elcom Tech. This segment makes precision timing and frequency control products for communication satellite payloads, terrestrial telecommunications infrastructure, and components and systems for the US military. The product list runs through rubidium atomic frequency standards, including an advanced digital rubidium clock released in 2022, space-qualified quartz oscillators, frequency synthesizers and direct digital synthesizers, reference generators and DC-DC converters. FEI-Elcom Tech contributes RF and microwave modules operating up to 67 GHz and electronic warfare subsystems, which is a meaningfully different business from atomic clocks and is often overlooked in descriptions of the company.

The second segment is FEI-Zyfer, based in California, which builds GPS-referenced time and frequency systems for military and commercial customers. Its catalogue includes the CommSync II rack systems in 3U and 2U redundant modular configurations, the GSync 1U and GSync II 2U systems, and the compact NanoSync IV and NanoSync IV Low Profile units. What distinguishes these from commercial network timing gear is the GPS receiver option: authorized US and allied military customers can specify SAASM or M-code encrypted receivers rather than civilian C/A code, paired with rubidium or OCXO oscillators for stable holdover when the satellite signal is lost. FEI-Zyfer also supplies M-code GPS receivers and multi-channel receiver and downconverter assemblies. Markets named for the segment are military, communications, public safety and network synchronization.

End applications reach across satellite payloads, C5ISR and JADC2 architectures, electronic warfare, missiles, unmanned aircraft, manned aircraft, GPS, secure communications, energy exploration and both wireline and wireless networks. Customers include NASA and the large primes, and FEI has repeat business from Lockheed Martin on GPS III and received a Northrop Grumman supplier excellence award in 2025.

Recent work has pushed toward lunar infrastructure. FEI won a roughly 7 million dollar contract in March 2026 for compact high-precision atomic clocks supporting position, navigation and timing for a lunar mission, followed by an approximately 8 million dollar follow-on production contract in July 2026. The company has publicly set a three-year revenue target of at least 150 million dollars. It trades on Nasdaq as FEIM, employs roughly 242 people, and is led by chief executive Thomas McClelland.