[time-nuts] GPS Antennas

[Dan Kemppainen]

Hi All,

Just to be clear, the request was about which multi-band antenna to buy. 
I'd like to play with the new F9P or F9T GPS modules. The Chinese unit 
from ebay is now in hand, and I need a free weekend to build a mount for 
the house.

For those concerned with the lightning aspect, The hits were not direct. 
The long wire on the GPS antenna is the suspected culprit. Even with 
surge protection on the coax, the antenna died. The antenna was mounted 
on a tower next to a remote garage, with coax to the house.

The new GPS antenna is going to move from the tower to the house (~200ft 
shorter coax). The tower itself (at the remote garage) has four ground 
rods bonded to it, and it's also tied to the 6" steel well casing (220ft 
deep). The garage has two ground rods at it's service entrance. There 
are two ground rods at the house (sub panel fed from the garage). The 
house rods should be very low impedance, installed in very wet ground, 
driven below the basement footings when those were exposed.

Anyway, I think this will solve the lightning issue. And hopefully give 
multi band capability too.


Thanks for all the input!

Dan







On 10/16/2019 12:00 PM, time-nuts-request at lists.febo.com wrote:
> 
> If your other gear survived, likely, the lightening hit was an indirect one.? If you do install more rods near antennas, it is extremely important that those rods are connected/bonded to the house main feed grounds at service entrance via low impedance/resistance connection.? How exactly this needs to be done is a very deep science people make living out of.? Without this antenna-ground-to-main-ground-connection, there will be enough potential difference that your stuff will blow again.
> In State of Florida where I live, and the lightening capital of the United States, the code says, stick two rods in the ground and call it done.? This is not even close to enough for lightening protection.? It's barely enough for personal protection.? I have five rods at the moment.? I plan to add many more as time and resource permits.? I'd like to have ten rods at least.
> Good luck and let's all be safe!
> 
> ---------------------------------------


> ------------------------------
> After two hits, I'd consider a lightning rod or two near the antenna,
> with the air terminal well above the antenna, but not connected to that
> antenna.
>