Here’s How To Test and Screen Multistage Arrestors – Check Out The New Technical Note!

Although this new Technical Note covering how to test/screen an arrestor to ensure that it is working and operating properly was specifically created in reference to our FPL series of units designed to protect GPS and other Global Navigation equipment…the input here also applies to the majority of the NexTek FPL and FPN series units.  Most of the FPL and FPN series, including the FPL GPS arrestors, use multiple stages of protection circuitry inside. 

This relative complexity makes the FPL and FPN series Fine Protectors a bit more complex to test properly, when compared to other common types such as Gas Discharge Tube or Quarter Wavelength Shorted Stub arrestors.


Operational/Protection Voltage Testing

  • Without an actual lightning tester (such as the common 1.2×50µs / 8×20µs Induced Lightning waveform testers,) it is difficult to completely verify Transient Response and Performance.
  • The lowest-voltage component is usually the only one that can be tested using a Diode Tester or Slow Rising DC Power Supply & Multimeter combination.  For NexTek FPL and FPN series devices, this usually means a fast-acting semiconductor Protection Diode that is responsible for final energy cleanup.  However, this component is usually the least robust in terms of Transient Current Handling so if it remains intact and operating within specs…the entire unit should be working OK.
    • Test Voltage Levels – Units may have +1V, +3.3V, +5V, +12V, +24, or other common Protection Voltage ratings

Continuity and Insulation Testing

  • Any FPL or FPN series units that are rated to pass DC Power through the unit will test positive for continuity between center pins, when using a Multimeter tool.


RF Thru-Performance / Proper Radio Operation

  • One of the simplest ways to test the basic functionality of any arrestor, not just the FPL and FPN series units, is to test the unit in a radio installation and verify proper system operation.  This alone is a positive indicator that the unit is operating properly and is probably not damaged.

Download Technical Note and Learn More

Technical Note – NexTek Arrestors – Servicing and Testing Multistage Units [FPL + FPN] .PDF

Technical Note – NexTek Arrestors – GDT Arrestor Testing & Screening .PDF

Blog Post – Testing Gas Discharge Tube Arrestors

Protecting Radio Equipment from HEMP/NEMP High Speed Transients – Coaxial Arrestor Threat Type Spotlight

This post is about protecting against high speed HEMP/NEMP pulses, one of the many types of transient threat that NexTek arrestors provide protection against.  Although Lightning energy is the primary source of damage to coaxial lines and systems where they are used, there are also other types of Surge Energy that can cause damage to electronics.

HEMP, NEMP, EMP Effects over USA
Map of Estimated Effects of High Altitude EMP Blast over the United States

HEMP/NEMP, or High altitude Electro Magnetic Pulse/Nuclear Electro Magnetic Pulse, discharges are among the most rare types of coaxial transient threats…but also among the most potentially damaging!

Damaging Nature of HEMP/NEMP Threats – The high-speed and extremely high energy nature of HEMP/NEMP transient events means that most modern electronics are left vulnerable to damage or permanent failure.  The total energy contained within a nanoseconds long pulse has hundreds of kV or potential and multiple kA of current.

Difficulties in Providing HEMP/NEMP Protection – Providing protection against high-speed transient energy pulses such as those caused by HEMP/NEMP events can be extremely challenging for coaxial RF applications for one important reason;  some of the Transient Energy can actually be within the normal pass-band of the radio/system during normal operation.  This type of conflict makes it difficult to provide optimal (minimal loss) performance during normal system and radio usage but also maintain adequate high-speed Transient response to provide protection against this type of high-speed threat.

To learn more, discuss your requirements, or receive feedback regarding protection options for your application…Please Contact Us!


How to Determine Protection Level Requirements and Identify the Correct Solution – When examining a specific application and to quantify the EMP threat level so as to inform the selection of appropriate protection, there are two main paths to travel down:

One, the EMP threat may be given by a specific Industry Standard document (MIL-STD, IEC, IEEE, EN, etc) according to a judgement made upstream in the overall program… Second, in the absence of a specific requirement…you can determine an approximate threat level or desired protection level based on the program-level requirements, estimated risk, and even things like the estimated cost of protection.

See below for a table which lists some EMP Requirements which may apply to a given application:

  • MIL-STD 188-125-1
  • MIL-STD 188-125-2
  • MIL-STD 461, multiple subsections
  • MIL-STD 464, multiple subsections
  • IEC-61000-x-x, multiple subsections
  • Or any others that deal with E1, E2, and E3 Pulse Types
  • Also Related – IEMI Standards

Learn More:

Threat Type Page – HEMP/NEMP Protection

Coaxial Surge Arrestors – Home Page