For more than four decades PolyPhaser has worked to become the authority on lightning and surge protection.

Top defense contractors rely on the experts in highly specialized EMP/HEMP filter technology at PolyPhaser and Transtector systems. Their design experience and patented technology allows them to meet requirements set by military standards for EMP-EMI mitigation. 

This proven technology and unique surge protection design is now being expanded to support commercial network operators as they plan HEMP network threat assessments.

surge protection against lightning
Protecting Critical Assets

Power and signal integrity has a role in critical asset protection. If the application is key to revenue and growth or necessary functionality, it must be protected from malfunction and downtime. PolyPhaser offers assurance to numerous key markets that rely on their critical electronic equipment and communication links for strategic functions, growth and stability.

How are EMP HEMP Tested Surge Protectors Different from Standard Devices?

  • HEMP Tested RF protection by PolyPhaser is tested to MIL-STD 188-125.
  • They are effective against the HEMP E1 and E2 pulses.
  • They provide fast response time, low inductance surge path and enhanced shielding characteristics.
  • Military grade staged hybrid protection circuit designs are available.

What is HEMP?

HEMP refers to an electro-magnetic chain reaction created by a nuclear explosion detonated high above our planet’s surface, where the gamma ray pulse from the payload reacts with the earth’s atmosphere to create a multi-stage electromagnetic pulse event. Learn more.

Military HEMP Standard

Today, the pulse current injection (PCI) testing included in Military Standard 188-125 sets the ultimate benchmark for product performance in HEMP applications. Transtector and PolyPhaser test all of their HEMP Tested products to this key standard to ensure a high level of protection.

MIL-STD 188-125 was developed in the early 1990’s to describe the threat environment, test methods and minimum protection requirements for HEMP hardening of fixed and transportable ground-based facilities that perform critical, time-urgent command, control, communications, computer, and intelligence (C4I) functions. The standard assumes the need for absolute critical command and control with no margin for disruption of command chain communications. These tests are severe and pass requirements are extremely high, since the intent is to preserve the executive chain of command of the US armed forces.

Product Highlights:

  • RF Surge Protection
  • RF Filtering
  • RF Interconnects
  • Data Surge Protection
  • Grounding


Using innovative filter technology, PolyPhaser’s HEMP Tested RF products, systems, and solutions are engineered to address the EMP protection requirements for critical infrastructure networks.


PolyPhaser’s RF surge protection platforms include DC Pass, DC Block, Bias T, Ultra Low PIM, and customized integrated solutions to protect your critical equipment from damage and loss of downtime.

Learn about the four pillars of protection you can implement to guard a system against HEMP and EMP: surge protection, grounding, shielding, and filtering. And listen in for an extra bonus pillar: backup power.

In this Spirit: Behind the Screen podcast, Dan Rebeck and Adam Perone of Transtector and PolyPhaser discuss HEMP protections

Whether you’re concerned about facilities, high-reliability military equipment, or your local community networks, electromagnetic pulse (EMP) could disrupt your day-to-day capabilities. From leaving you without power to leaving you without data or sensitive equipment, having a plan to address EMP now protects you from equipment loss in the future.

Add in high-altitude electromagnetic pulse (HEMP), which can generate 3 separate strong EMP events, and our vulnerability becomes much more complicated.

Product News


HEMP Tested Type N F/F Bulkhead Coaxial RF Surge Protector, 10MHz - 700MHz, DC Block, 500W, 20uJ, 50kA, Blocking Cap

PolyPhaser coaxial RF surge protector (also known as lightning surge protector, lightning surge arrestor or suppressor) HT-RI-E3PM-BNFM is in-stock and will ship same-day as purchased. This radio frequency surge protector / lightning surge arrestor helps protect your equipment from electromagnetic pulse (EMP) or power surges that are commonly caused by lightning or other strong electrical changes. This RF surge protection device is also HEMP (high-altitude EMP) tested. Our radio frequency coaxial surge protector product is commonly used for radio and antenna installations where part or all system equipment is outdoors to protect sensitive equipment and is designed to pass 10 MHz to 700 MHz while suppressing DC surge.