Blitzortung.org Forum

Hello,

i play in my mind with the idea to participate to the network with a system blue. After study all the documents i very well informed. But there are some questions left who i didn´t find a answer what satisfy me. 

It´s planned to mount the system on top of the roof of a hall 50m x 50m with 15m height. The complete structure, including the roof, are mostly made of metal. There are not many electrical intereferences around, just some LED lamps inside the building. I don´t expect many noises from them.

I´m aware that i have to search a perfect place for the antenna a while. But maybe there is someone who already tried such kind of configuration and can give me a short information if these is possible or if it´s a complete disadvantage. From my HAM Radio experiences i know that metal below a Antenna can decide over sucess or failure. Thats the reason why i ask before i start with the project. 

There is one more thing, whats about the cable length between controller and amplifier? I have a suited place for the controller, but this require cabling length around 40m. Not sure if the system will work properly if i do that. Is there anybody who have some experiences about this? Somewhere i read about 30m as maximum. 

Thanks in advance for your answer.

Greetings from Germany

Flo

If you can use LW radio. You can also use the VLF antenna (Loop or Ferrite)
E-Field antenna must sit outside - You can use either H-Field or E-Field or both

As the cables to the antennas often sit near other cables that interfere, we I set a limit of 30m - If the cable is free for nearby cables, it can easily be 40-50m
The resistance of a wire in 50m cable is 4.2 ohms, so it makes no noticeable loss.

/Richo

Hi Richo,

thanks for your reply. 

I´m really going for ferrit antenna for the H field. Of course, there is enough space on the roof, but i can´t go very high. The lightning rod are just 1,2m, so no place for a loop. Otherwise the lightning could strikes direkt the antenna... ok, also a form of detection
There are no others antenna on the roof, because the same reason i wrote above. 

Cables lengths untill 50m sounds very good for me. No other cables next to it. Could work.

I think i give it a try. There is nothing better then a try and error experience

(2016-06-06, 13:06)RichoAnd Wrote: [ -> ]As the cables to the antennas often sit near other cables that interfere, we I set a limit of 30m - If the cable is free for nearby cables, it can easily be 40-50m
The resistance of a wire in 50m cable is 4.2 ohms, so it makes no noticeable loss.

When we speak about resistance, CAT 6 is still better : 22 AWG instead of 24 AWG. 
22 AWG = 52.96 mΩ/m
24 AWG = 84.22 mΩ/m

But according to what you write, there is no need to invest in expensive cables

No! as long it's shielded