Home |
Search |
Today's Posts |
|
#1
![]() |
|||
|
|||
![]()
I wouldn't think anything but extremely good grounding
at the antenna will do much. Long ago, when I lived on the west central coast of Florida (lightning alley), I had a 6-meter repeater on a tall building. The transmit and receive antennas were at diagonal corners of the building (no duplexer). We got a direct hit on BOTH antennas. The damage was something to see. Antennas had no damage except some scorch marks, but the coax was another matter. There would be 2-3' of coax, then 2-3' of nothing but scorched roofing. This repeated across the entire 150' or so length of the coax! A whole bunch of RG-8 simply vaporized. Steve |
#2
![]() |
|||
|
|||
![]()
Steve wrote:
"I wouldn`t think anything but extremely good grounding at the antenna will do much." That helps. Company I retired from had radios all over the world. Most base stations used Andrew 1/4-wave stainless steel folded monopoles. These were securely grounded to the tower. The tower had a separate ground rod connected outside the base to each leg of the tower by heavy strap or cable. These radios suffered no lightning damage, despite repeated hits. Kraus has this to say in kis 3rd edition of "Antennas" on pages 719 and 720: "---a short-circuited lambda/4 section of coaxial line is connected in parallel with the antenna terminals. This widens the impedance bandwidth and also places the stub antenna at dc ground potential. This is desirable to protect the transmission line from lightning surges." Whenever we could not use a folded antenna with a single-frequency radio, we connected the shorted stub directly across the antenna and grounded the coax at the tower top. It works. Best regards, Richard Harrison, KB5WZI |
Reply |
Thread Tools | Search this Thread |
Display Modes | |
|
|
![]() |
||||
Thread | Forum | |||
Building a 'simple' Attic Loop Antenna = Not So Simple ! | Shortwave | |||
FYI: NOAA Lightning Safety Awareness Week | Policy | |||
Antenna experiment, coax shielded loop | Shortwave | |||
The "TRICK" to TV 'type' Coax Cable [Shielded] SWL Loop Antennas {RHF} | Antenna | |||
The "TRICK" to TV 'type' Coax Cable [Shielded] SWL Loop Antennas {RHF} | Shortwave |