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Lightning Protectors Description

Quarter-wave Stub Lightning Protector

lightning protector

The IEL lightning protector works on the principle that a short circuit quarter-wave stub acts as an open circuit on the wanted frequency and looks like a short at the low frequencies associated with lightning energy.

Lightning Energy peaks between 100kHz and 10MHz. Our range of stubs provide a high current direct path to the coax ground and the station ground via a substantial brass fitting housing the stub.

Advantages over Gas discharge Lightning Protectors.

Gas discharge lightning protectors work on the principle that the working voltage of the transmission system is much less than the strike voltage of a gas discharge tube mounted in coaxial fitting that shorts the inner to the outer conductor of the coaxial cable when the strike voltage has been exceeded.

Three major flaws addressed by the IEL Lightning Protector

  1. The minimum strike over voltage obtainable is 90 volts and it takes time albeit short for the tube to start conducting this presents voltages in spike form of up to several hundred volts before the tube strikes and holds the voltage constant. This is not good for multi coupled receiver systems.
  2. For Transmitter systems higher strike over voltages are used so that the tube does not strike over on the applied RF. Unless substantive protection networks are applied around modern solid state FET amplifiers the high voltage spike before strikeover of the tube is well known to destroy or damage the final amplifier.
  3. The gas discharge tube is not immortal and unless a lightning event counter is added to the system (at considerable expense) there is no way of telling if the gas discharge tube is still working to specification.

Disadvantages of Quarter-wave stub Lightning protectors

  1. Narrow bandwidth typically half an octave or lower compared to the Gas discharge type which has several decades of suitability.
  2. The coax is shorted at all times making phantom powering of tower top pre-amplifiers difficult.

Lightning Protectors 400 - 520MHz

PricingQty 1-9Qty 10+
POA
400-450MHz$170POA
450-520MHz$160POA

NOTE:These Prices are in US Dollars and do not include GST

©2008 IEL