I should’ve stated that I have an LNA at the antenna, but that’s what I’d be looking at. I would be going from a 15ft (i checked the actual length) to a maybe 30ft cable.
I think I’ll just get the 30ft and mess around with it once the full Florida summer heat arrives.
I have 150 ft of RG6 cable after LNA.
I was thinking more along the lines of diminishing returns. I’m currently battling a few sites in my area for top spot and want to keep it that way.
I probably don’t have as nice of a mast as these other sites, but I probably have better equipment and that helps a bunch.
If I can squeeze out an extra one or two percent by moving the airspy and rpi indoors, I would do it. But at these short lengths it’s probably negligible when looking at the thermal noise.
Thermal noise gets generated in the receiver stick. Not in the cable.
That’s why I suggested moving that inside. Especially if you already have a LNA
I feel like an underachiever after seeing some of these setups but I’m limited to an apartment (I’m disabled and this place works well with my limitations so please don’t “HOA” me) and I can’t mount anything outside so I have one of those PCB antennas from eBay mounted to the (nylon, not metal) screen of my living room window with one of the blue dongles and a Raspberry Pi 3B+ and I can pick up planes 200 miles away (occasionally even as far as 250) and track about 500 planes daily. The Pi sits on a bookcase next to the window and the coax run is as short as I could make it. There are two others in my area also running PiAware and my stats are in between theirs so considering my limitations my setup seems to work rather well. Being on the top floor of my apartment building helps a lot too I’m sure. I experimented with several spider antenna builds and the PCB antenna seems to work as well or better than any of them that I built. It is most likely due to a lack of experience on my part but it has been fun trying to figure out what works best for me.
Nothing to be an underachiever.
Many users do not have this range, independent from what they’re doing
You seem to have the right place and the best reception with your setup.
At some point you could try a FA antenna or some DIY, but that is only optional.
My first setup was similar, i was not allowed to mount something outside, so i tried to optimize the current indoor setup.
Every feeder helps the overall product. It’s a hobby, and getting to where you are now I’m sure has taught you some things. If this wasn’t fun, we wouldn’t be doing it 
Don’t write off those PCB antennas and spider antennas. They perform really good. Problem with bigger antennas, because of physics, you need a lot more care placing them as far as possible from anything else. For a spider, or any electrically short antenna, you can put them around 30cm from anything else, and they will not be influenced. The longer the antenna, the further you have to keep them from anything else. Even the PVC-sleeve you put over a perfectly tuned, but open, 10-element collinear will totally destroy their performance.
CPU is reading 74’C now and it’s sunny and 65’F outside so I’ll be adding a fan in March. Glad I didn’t cut those red/black wires too short.
Notice how all of a sudden everything except the peak level jumped up?
I’d like to lower that back down so the spread between the peak and weakest is as great as possible. Would I increase or decrease the gain to accomplish that?
you need to look at message rate and aircraft seen also. Looking on the signal level only does not give you the answer to your question.
There’s message rate and aircraft seen for the same time period. I’m not sure what they indicate as far as gain level adjustments.
It’s really difficult to spot subtle changes, in such a dynamic system as aircraft movements, over a short space in time.
One approach to the problem is to make a change, wait a few days, and then compare statistics with a nearby feeder with similar performance. This is still quite subjective, and aircraft positions does not necessarily follow aircraft tracked.
Another method is to run two feeders, leaving one unchanged, making changes to the other. When an improvement in statistics is achieved, these changes can be made to the reference system too.
Either two separate receiver chains can be employed, or one antenna, LNA and filter which is then split 2 ways to two SDR dongles and one or two RPI. This gives near real-time observation of the effect of relatively minor changes. (Well, a few hours rather than days).
Other approaches are available, such as wiedehopf’s excellent gain setting script.
You really don’t need the script to do what it does.
But people like that it’s automatic.
It targets 0.5% to 10% messages >-3dB.
That’s shown in the graphs as well and setting the gain so that the above target is fulfilled is really easy.
What a reasonable target is, is debatable, if you want to never lose low flying aircraft less than 5 to 10 miles from your receiver, i’d consider a lower percentage.
I have kept my ‘first’ installation very simple it is the out of the box BLUE system from FA. I am new to ADS_B and data recording but understand it very well as aviation is a hobby of mine
Does Flightaware sell a “System”?
As far as I know, they sell individual components (antenna, filter, prostick etc) through Amazon.
The “System” is sold by 3rd party vendors using Flightaware components + cable & fittings they acquire from some other vendors.
They advertise / list these “System” in a way which gives impression these are sold by Flight aware. Generally these “Systems” are over-priced.
I am not sure if they retail their system as I got mine on the ‘FREE’ scheme where they have an area in the world that needs more data feeds and they supply the kit to build up the network. To get this kit you have to make an application and complete a set of questions regarding the propsed site of your installation. It is a good scheme and as such gets people up and running with this data-feed community. Yes it is ‘probably’ a basic system but it works very well for me as I get good coverage of flflights to and from Mauritius where I live .
Oh, ok, I misunderstood that you purchased a “system” from sellers on Amazon.
Now it is clear that you got a “Flightfeeder” supplied free of cost by Flightaware.
Indeed, that is called a “Flightfeeder” and is not available retail.
It’s basically still FlightAware property, you just letting them use your location and infrastructure.
Pi is on top Left, Antenna is a Flightaware stick on my roof. Even though I am above my roof line the mountains to my NW block a lot of lower ALT signals. Although able to see ATL traffic down to 11K feet.
The Pi feeds the Dual Hexa-core Xeon Server w/HT, 48GB ram, and few TB of storage. It runs the Virtual Radar, A Plex Server, various game servers, some VMs when I want to mess around, Backup and data storage.
Router, Switch and Pi are on a Battery backup and have a approx run time of nearly 2 hours. Server has it’s own but will shutdown after few minutes as it’s run time is only 10-20 minutes depending on load.
Virtual Radar site:
http://kcharadar.jumpingcrab.com/
