Definition of a good noise-free site for BlitzOrtung probe
#1
From my understanding, the probe should be at least 10 meters away from any electrical equipment.
I am planning to put the probe on top of an old building.

My site is on the French country side, in a very rural area, but :
* I don't have a clear view on sky, because of a small hill. Does it matter?
* I can view a 4G mobile phone emitter, 5 kilometers away. Will it spoof the probe?

Kind regards,
Kellogs
Reply
#2
You'll probably have diminished reception in that direction. In the context of things, probably not an issue, since yours is one of many. 4G phone emiiter - what us Yanks call a cell site - will have no effect. Blitzortung is looking at under 1 Mhz. Cell site is ~1-2 Ghz - microwave. No effect whatever.

So some questions. You talked of "probe". That's e-field. What of the h-field? What are you going to use? ferrite, or loops? Is the Receiver going to be in this old building, or someplace further away? Remember that you should keep some distance between whatever you are using for power supplies - switching type - for the Blitzortung, and whatever network gear you have for it. One thing that really helps sensitivity, and keeps the noise down is to run the coax for the probe past the electrical ground for the building and use a grounding block at that point as though it's a satellite antenna -I assume those type of practices for protection are global. Here's a link to a diagram as it applies in the US to antennas. http://www.mikeholt.com/download.php?fil...014NEC.pdf

Of interest is image 810-3 and 810-4. Make believe that the antenna in that is the probe, and the "TV" is the Blitzortung receiver. The concept is the same. It picks the noise from equipment inside the building off the coax.
Stations: 1156
Reply
#3
Thank you for explanation.
Reply
#4
A 4G cell might be down in the 800 MHz band, though as you say not an issue for a Blitzortung receiver and 5 km is a long way.

Depending on where in France Kellogs is the VLF ransmitter near Rosnay might be more of a problem as it uses 18.3 kHz, 20.9 kHz & 21.7 kHz, possibly not all at the same time.

Any chance of that link pointing to a file on the web somewhere rather than a file on your local C:? Grounding of aerial downleads is not a global practice, doesn't happen in the UK. But the laws of physics don't change and if it reduces noise...
Cheers
Dave.

Stations: 1627
Reply
#5
Only thing that need good view of sky is the GPS antenna.

I am currently running my station in the basement of my house.

GPS antenna is placed next to a window and works fine.

I plan to relocate to my garage which will be final location, just have not gotten it there yet.
Kevin McCormick KB0UOI
Macomb, IL USA
Stations: 1539
Reply
#6
(2017-05-13, 22:16)allsorts Wrote: A 4G cell might be down in the 800 MHz band, though as you say not an issue for a Blitzortung receiver and 5 km is a long way.

Depending on where in France Kellogs is the VLF ransmitter near Rosnay might be more of a problem as it uses 18.3 kHz, 20.9 kHz & 21.7 kHz, possibly not all at the same time.

Any chance of that link pointing to a file on the web somewhere rather than a file on your local C:?  Grounding of aerial downleads is not a global practice, doesn't happen in the UK. But the laws of physics don't change and if it reduces noise...

Missed the fact the link was a local file. Fixed in post.

Also, with regard to the 4G frequencies, I was talking in generalities about the frequency ranges. In many countries, the frequencies used for 4G / LTE ranges from low 700 Mhz on up through 5700 Mhz (US T-Mobile). I was just trying get the point across that cell sites at any reasonable distance - outside of VLF noise from power supplies and the like if you were right near the building - are completely invisible to the Blitzortung receivers.

Thanks for pointing out the bad link.
Stations: 1156
Reply


Possibly Related Threads...
Thread Author Replies Views Last Post
  Another New Site Review. Phil23 16 1,100 2017-07-30, 18:36
Last Post: pasense
  national radio quiet zone site davidsaroff 3 948 2017-04-29, 15:00
Last Post: Max_Headroom
  What is good station quality? cbhiii 8 1,496 2017-03-30, 03:30
Last Post: cbhiii01



Users browsing this thread: 1 Guest(s)