FlightAware Discussions

Setup and Antenna position - USB to RJ45 an option?

Hello. I’m new here, thanks for having me.
Looking for some advice regarding setup.
I started with a little magnetic base antenna off amazon and very quickly moved up to a FlightAware 1090MHz ADS-B N-Type Antenna 26" (and a 10m cable).
Due to cable length and pi positioning the antenna is currently mounted IN MY ROOF SPACE.
My tile roof is also lined with what looks like aluminium insulation (the stuff that comes on a roll) which I guess is working like a faraday cage and is likely to be reducing my max reception.

This what I’m getting now.
Imgur link due to being new

I have two possible options for getting the antenna out of the roof.
Option one - mount the antenna on the tv antenna mount already on the roof.
The issue of cable length then comes into play - due to the fact this is the worst roof space I’ve ever been in (it’s a rental due to being relocated with work) I don’t want to put the pi in the roof space (heat would become an issue and I don’t want to have to get up there to fix issues, PoE not an option at this time).
If I put the FA pro stick in the roof would a usb to rj45 extension work?
I’ve read review of these and it seems they’re ok at USB1 devices, not so good for USB2. Also not sure how the power drawer of the FA pro stick would work.
If these did work the antenna could go on apex of roof and my pi will sit where it currently is plugged into my network.

Option two - I can install a mount on the eves of the house and mount the antenna just above gutter height.
The pi will still be inside connected with wifi rather than ethernet and no further extensions are required.

If option two is the recommended option - would the height of the bracket make much difference. Here are two height options I have.
Shorter option 300mm $28.49 AUD
Higher option 1400mm $57.74 AUD

If I go with option two would the tree cause much interference?

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Welcome!

microwave RF is very much ‘line of sight’, so getting your antenna up above local obstacles will be the single best improvement you can make.

I’ve used short (200mm) usb extension leads and seen a 50% drop in performance (others have reported no drop with long leads), so try it by all means, but don’t be surprised if you don’t like it.

For $8 delivered (not expecting much) I’ve got the USB to rj45 ordered. I’ll make up a test CAT6 lead and try it out. Is there anywhere I can see performance or do I simply look at what I’m picking up?
Even with the tree - I’m expecting better performance with the antenna being outside rather than in the roof space (behind aluminium).

Start by installing @wiedehopf’s graphs. Then you’ll have some history of your sites performance when you install the long cable.
My suggestion is to add the cable without moving anything so you know what difference (if any) it made.

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+1 for installing graphs1090 1st. I had my aerial moved from inside the roof space to on my chimney and seen a marked improvement. *especially with MLAT positions)
If I were you I would go for Option 1 and use the shortest USB possible in your scenario. (with option 2 your house is going to block that whole side of the sky?

I’ve installed graphs1090.
If I install on my current tv antenna mast I’ll need about 10meters to get from the pro stick to the pi. I don’t think a USB extension will work at this distance - that’s why I was wondering if running it over CAT6 would help/work.

10m is quite acceptable for a coax run. The better the coax, the lower the attenuation (and the higher the price!).

Mounting the dongle at the antenna (and running a long USB cable) still requires a weather proof enclosure. If you do that, you may was well use a bigger box and mount the Pi in it as well (then you need ethernet and power).

It’d be easier to use a good quality coax - say LMR200 as a minimum up to LMR400 if you can put up with the thicker, stiffer cable (plenty of similar/equivalent cables available).

Hey all.
So after a few days thinking about it a third option came to mind.
I got hold of an old roof tile foot mount - used for solar panel installations. (Got given two second hand ones from a solar installer for free.)
This meant I was able to mount the antenna on the roof without running into cable length issues.


(Mark II may be a little taller and more upright)

It’s made the difference I was hoping for.

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Remember to now set your gain if you have not already done so.

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Gain has now been adjusted - still working through the finer details of getting it just right.
I’m tracking small planes overhead without dropouts and larger planes out to about 180nm.
Thanks for your input.

Just upgraded my mount to MK II.
I’ve posted more detailed pictures on a seperate post.

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