Mohd Nazry Mustapa wrote:
"Anyone know how to make a simple lightning arrester (Homebrew) that
really work in case of lightning?"

I`ve found shorted (folded) antennas are less susceptible to lightning
overload than are open-circuit antennas.

A folded VHF monopole fed by coax and well grounded at the tower top is
nearly immune to lightning.

Coax, inside, rejects common-mode propagation of lightning energy. Coax,
outside, needs good grounding to make a good path around (bypass for)
protected equipment.

The equipment needs direct low-impedance grounding so that most surge
energy is dropped across the coax, not the equipment.
Coils of extra coax may be used to raise the impedance of the outside of
the coax.

Equipment is still vulnerable to excess differential voltage on the
power wires. Perhaps, excess common-mode voltage too. Manufacturers make
brute-force L-C pi-network low-pass filters for each power wire
connected to the equipment. These can be homebrewed if desired. They are
important in delaying the surge on the power source lines to give time
for the arresters time to spark across, giving protection to the
equipment. Arresters need to be fast acting and placed to protect
line-to-line and line to ground. These low-pass filters and arrestors
are suitable for power and control wires, not for antenna wires in most
cases. I`ve used lots of gas tubes on audio and control lines but never
on a coax cable where I believe they are superfluous.

I`ve used tower lighting RF chokes for the inductor in the low-pass
powerline filters to get the needed current carrying capability, and
various breakdown devices on the input and outpur of the filter. MOV`s
work well. They are fast and cheap but may require replacement at times.

Power lines are susceptible to dangerous surges. Filters reduce the
bandwidth of energy that must be handled by the suppressor, just as the
folded antenna or short-circuit 1/4-wave stub across an antenna limits
the bandwidth of lightning energy that it has to accept.

Lightning and other related surges are just enormous noises. They can be
suppressed with the same techniques used with weaker noise. The
equipment must be sturdy to endure a lightning strike. Arresters may be
compared to sturdy noise clippers.

Best regards, Richard Harrison, KB5WZI