[time-nuts] Coaxial Lightning Arrestors

Stan, W1LE stanw1le at verizon.net
Fri Feb 29 19:19:46 EST 2008

Hello The Net:

At one time the ICE lightning arrestors did not pass DC, so DC on the 
coax center conductor
will be blocked and will not get to the preamplifier, up front at the 
antenna element.

Other lightning arrestors are simply a 50 ohm coaxial line with a gas 
discharge tube
between the center conductor and the outer shield. With an over voltage 
the gas discharge element conducts and shunts the voltage to ground.

When the transient over voltage disappears, the gas discharge element stops
conducting and operation is back to normal.

For low level rain/precipitation static, the gas discharge tube will not 
shunt the noise to ground.

Lightning can blow up a gas discharge element, So a periodic inspection 
serves a purpose.

These gas discharge elements can be spec'd for RX only, with a lower 
conduction voltage
or much higher to run lotsa RF power, as with a transmitter.

Looks like disposal of the gas discharge element is controlled in 
Germany, as are smoke detectors.

But like smoke detectors, here in America, these small radioactive 
wastes are handled like household trash.
Maybe some municipalities have regulations.

Be sure to understand if your lightning protector will pass DC or not, 
and is suitable for your frequency range.

Stan, W1LE   FN41sr   Cape Cod


More information about the time-nuts mailing list