Lightning protection for GPS antenna

[sixtimesseven]

Hi

I'd like to mount a GPS antenna for both gpsdo and as an rtk base station on my roof.
For both applications it should have an open, unobstructed view of the sky. The house has lightning protection fitted and there is a cut down to the roof level antenna mast (for old TV antennas) on the very top, which is already attached to the lightning system. So far so good for the lightning arresting part I guess(?)

However, what kind of protection do I need on the inside? As far as I could gather there should be an earthing point right after entry into the house. Something of that kind: https://www.amazon.com/Lightning-ARRESTOR-Ham-Base-Antennas/dp/B01LYK5TU5

However, I did not really find anything for the frequency range in the ham space nor do the WLAN / amazon type arrestors in the 20-20 bucks range look particularly trustworthy(?)

Also, where the antenna rod goes inside, there isn't really an earthing connection available. Would I just run a 2.5mm2 PE cable from the next outlet / distribution box to the surge protector (about 10m and from there another 15m down to the houses earthing point).

I guess an additional arrestor / overvoltage protection circuit would also be in order since the arrestors I've seen so far in the ham space seem to work with gas discharge tubes and I do not think a gps module likes >50V on it's input 

[trobbins]

Perhaps a sketch of all the parts and cables and equipment you have described would be so much easier to appreciate and then make comments on.  That should also include an expected path that transient currents would take, and include the mains power distribution and how that gets back to earthing points and where it could be susceptible to transients coming in from other circuits that may receive lightning ingress, and where earth potential rises could originate.

[BravoV]

I'm no expert, its just this is current my setup.

This is what I'm currently use -> PolyPhaser DGXZ-06NFNF-A , as its designed to pass DC bias voltage 5 V for the antenna's LNA, and suitable for GPS freq @ 800MHz up to 2.5 GHz.

They claim its capable to withstand multi strikes without the need of replacing the GDT tube as in ordinary types.

Took few photo shots when I received them.



Below is the recommended lightning protection scheme and illustration from HP 58503A/B GPSDO manual on the wirings, watch carefully the ground wirings, there two earth connections, and joined at some place at the ground, pointed by red box.