What type of receiver setup do you have? Where is your antenna located? Anything interesting or unusual in your setup? Let’s see it!
I’ll go first.
Here’s my setup for location #11261. It’s pretty standard with off-the-shelf components. Computer: Raspberry Pi 2 Model B running PiAware SD card edition. Receiver: NooElec NESDR Mini 2 (with R820T2 tuner) Antenna: FlightAware antenna. No amplifier or filter. The location is quite far from potential sources of interference. Cable: 10m of CO100AF with an N-male connector on the antenna side and a SMA-male on the other, plus an SMA-to-MCX pigtail with 6" of RG-316. Location: Antenna is mounted about a third of the way up a 2m mast on top of a ~12m tall solar observatory tower. The tower is very nearly at the top of a 950m-tall hill just south of Bern, Switzerland and has a clear view to the horizon out to 250nm from 90 degrees west, through due north, to 90 degrees east with certain sectors having ranges of 250+. Coverage to the south is limited due to (a) the mast to which the antenna is mounted and (b) the Swiss Alps. Interesting Notes: From this location I can observe most air traffic in Switzerland, as well as all traffic in/out of the Zurich airport down to an elevation of 4500ft AGL. Zurich traffic alone makes up about 10% of the reported positions visible to this station. I can also see flights at 30,000+ft over Frankfurt, Munich, Luxembourg, and France (nearly to Paris).
Here’s some photos (click to enlarge). Unfortunately the panorama-making utility on my Android tablet was a little confused and some of the panoramas didn’t stitch together quite right.
Nice write up of your stuff. I just have simple 2nd floor window mounted 8 segment coco or FA antenea. And basic PiAware setup. Rg6 quad shield cable 6 feet in length from antenea to reciever. I have a converter on the FA antenea to connect the rg6 cable.
I could do so, but I don’t have any standoff mounting arms. It’s also not my tower or mast, so I’m reliant on the goodwill (and willingness to humor me by putting some effort into helping me install stuff, provide power and connectivity, etc.) of the owner. I don’t want to get too greedy.
Even if the antenna was mounted a bit away from the mast, the Alps would still block signals from the south from around 60nm, so any improvement would be minor.
**HARDWARE: ** Raspberry Pi model B rev 2, RTL2832U R820T2 dongle, Perfect Vision 30db in-line amp, Direct TV power injector, ChannelPlus signal combiner, Holland DPD2 diplexer.
**SOFTWARE: ** OS is MiniBian 2015-2-18 (4th release). This is a minimalist Raspbian and compatible with the standard release. The RPi B is clocked at 900MHz.
dump1090-mutability v1.15~dev
piaware 2.1-2
ANTENNAS: 8-segment coco and a collinear wire antenna both in a window. House is elevated about 10 ft above ground level on a steep hillside, so no trees (not many anyway in high desert of Arizona) . Both antennas fed to the RTL2832U using ChannelPlus signal combiner. Collinear wire antenna similar to http://www.sprut.de/electronic/pic/projekte/adsb/adsb_en.html
LOCATION: Approximately midway between El Paso TX and Tucson AZ. Problem – live in a valley with low mountains on two sides restricting exposure to the main airline route to the north, but some exposure to the northwest and good exposure to southeast. Can see into the northern part of the state of Chihuahua, Mexico. On a daily basis log a few planes as far as 200-250 nm. Rarely log more than 100 aircraft per day with positions but have a unique vantage point into Mexico which keeps it interesting.
Using the http://www.heywhatsthat.com/ website (thanks to FlightAware member PeterHR for making me aware of this tool) I am completely in-line with what the site predicts my reception range should be based on geographic features.
**COMMENTS: **This setup using the small Minibian version of Raspbian with dump1090-mutability is a recent change from using the Piaware image. Advantage in that it doesn’t include all of the peripheral software of the full Raspbian which is unnecessary for a dedicated Raspberry Pi application such as this. Everything required fits on a 2GB memory card, utilizing only about 1GB. This includes a few extra utilities I added such as wavemon, rpi-monitor, sudo, nano, etc.
As far as moving to dump1090-mutability, it’s too soon to draw conclusions, but aircraft numbers have increased by around 25 percent and positions up by 2x. But large daily variances can occur due to weather related rerouting of aircraft – we’re in the midst of the monsoon season in the southwest US.
This combining of two antennas would bother me, in case of partial signal cancellation from certain directions (remember the double slit experiments done a school at about 10th grade [a long time ago for me]? en.wikipedia.org/wiki/Double-slit_experiment)
dschre wrote:
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ANTENNAS: 8-segment coco and a collinear wire antenna both in a window. House is elevated about 10 ft above ground level on a steep hillside, so no trees (not many anyway in high desert of Arizona) . Both antennas fed to the RTL2832U using ChannelPlus signal combiner. Collinear wire antenna similar to sprut.de/electronic/pic/proj … sb_en.html
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This combining of two antennas would bother me, in case of partial signal cancellation from certain directions (remember the double slit experiments done a school at about 10th grade [a long time ago for me]? en.wikipedia.org/wiki/Double-slit_experiment)
Theoretically that is the case, but as I am inclined to do with all of my various antennas (ADSB, medium wave, beverages for my SWL monitoring work, etc) end up trying multiple approaches. So far I have not seen degradation using the combiner. The wire collinear seems to have a somewhat different response to signals based on elevation angle. But I plan to do a more objective comparison when we are back to normal weather and more consistent aircraft counts.
I am liking Minibian and definitely think the dump1090-mutability is helping. Still using --gain -10
as for gain, Obj said look at /var/log/dump1090-mutability section below
Statistics: Thu Aug 13 05:17:10 2015 UTC - Thu Aug 13 06:17:10 2015 UTC
Local receiver:
8640135168 samples processed
0 samples dropped
0 Mode A/C messages received
30411940 Mode-S message preambles received
14978067 with bad message format or invalid CRC
10986335 with unrecognized ICAO address
4263911 accepted with correct CRC
183627 accepted with 1-bit error repaired
-14.4 dBFS mean signal power
-0.8 dBFS peak signal power
10745 messages with signal power above -3dBFS
Messages from network clients:
0 Mode A/C messages received
62355 Mode S messages received
0 with bad message format or invalid CRC
0 with unrecognized ICAO address
62355 accepted with correct CRC
0 accepted with 1-bit error repaired
4509893 total usable messages
144 surface position messages received
you want no more than 1 - 3 % of the usable messages to be over -3db
so 10745 * 100 / 4509893 = 2.38% for me
if I move the gain 1 step down, the figure goes to 0.3% … but I lose a lot of range.
Computer: Raspberry Pi 2 Model B running raspbian-ua-netinstall
Receiver: R820T2 RTL-SDR Adapter (cheapest one I could find on ebay)
Antenna: 8 leg spider
Cable: 30cm of WF65, inline amp, ~3m of WF65, flat cable window section, ~50cm RG6 into power inserter, 10cm RG6 into MCX to F adapter.
Location: Antenna is mounted at the top of 3m of PVC tubing. Unfortunately it isn’t above the roof line. I would like to get this attached to the chimney because there’s a lot more potential.
Software: dump1090-mutability - git
Computer: Raspberry Pi 2 Model B running Raspbian
Receiver: R820T RTL-SDR Adapter
Antenna: Cantenna
Cable: 6m of coax (RG58?) - no amp
Location: Antenna is mounted above a satellite dish at the front of the house
Software: dump1090-mutability - git
Extra: I had a spare RTL-SDR adapter and wanted to test another antenna.
With both of these, after 30 days I should be in the top 100.
you want no more than 1 - 3 % of the usable messages to be over -3db
so 10745 * 100 / 4509893 = 2.38% for me
if I move the gain 1 step down, the figure goes to 0.3% … but I lose a lot of range.
PeterHR
Finally got around to testing my setup and initially way too many messages over -3 dBFS. I experimented with different gain settings but somehow always ended back with gain -10.
However I decided to install a 10db in-line attenuator/DC block (DISH network salvage) which is producing the expected range and message counts and the signal level has moderated.
Here are the latest stats:
1.3% messages with signal power above -3dBFS
-9.9 dBFS mean signal power
-2.5 dBFS peak signalpower
I think the 10db attenuator is helping control the signal level, since I am using the 30 Db amp. So the gain control stabilizes the levels and the attenuator brings the entire level down slightly andprevents overload. Or am I just imagining how it is helping?
Time will tell.
if you really want gan 10 below max - don’t you set it to about 40?
(by the way, the 2 / 3% above -3db came from one of Obj’s posts)
That’s my understanding of gain -10. So I want to use AGC rather than a specific gain setting. For example, when set at “40” it really diminishes the signals whereas AGC is more even handed.
I did find obj’s post about interpreting the stats. Good info there.
May eventually have to set an absolute number. Because I don’t get a very large number of total messages in my location, there is a lot of variability in the data stats. But at least the dBFS range is under better control.
Computer: Raspberry Pi 2 Model B running Raspbian
Receiver: R820T2 RTL-SDR Adapter (you know, the blue version)
Antenna: DIY 8 elts coco made from TV coaxial cable
Cable: just pigtails to the LNA/Filter (HABAmp) and then to the dongle
Location: in the attic, planning to move it outside. The antenna is within a fiberglass fishing rod. I have a very good location on the top of the hill, especially to the north and north east.
Software: dump1090-mutability
Computer: Raspberry Pi 2 Model B running Raspbian
Receiver: R820T2 RTL-SDR Adapter (also the blue version)
Antenna: DIY 5 elts coco made from TV coaxial cable
Cable: just pigtails to the LNA/Filter (HABAmp) and then to the dongle
Location: in the attic. The antenna is within a fiberglass fishing rod. Location is much worse, just OK to the north.
Software: dump1090-mutability
I must feed quite a lot of MLAT data in the south/southwest UK, but we miss receivers near my place to gather more MLAT data for the flights around.
Computer: Raspberry Pi 2 Model B running FlightAware image. Receiver: NooElec NESDR Mini 2 Antenna: Stock antenna (working on a homebrew one)
Initially, the Raspberry stayed indoors, with the antenna placed in a westward window. I then move it up onto my roof out of curiousity, wondering how much an improvement I’d get. Needless to say, it’s stayed up there since. As time progressed, I added Apache and created a much more “polished” look to dump1090. I also added various PHP monitoring applications, as well.
I got a sprinkler timer housing for it. There’s enough room for the raspberry, dongle, and anything else I feel like installing at some point.
To do list:
Build (or purchase) a higher quality antenna
Install mutabilty.
Improve case ventilation.
This project is still very much a work in progress. I just need the skills, time, and money . Interesting fact: the vent acts as a ground plane for the antenna, so I get somewhat improved reception from it.
That looks very cool. Would you be willing to share the updates you did to add “polish” to the web interface?
Also, that sprinkler timer housing looks completely sealed: how hot does it get in the summer? Any issues with condensation? How does the antenna handle being outside? Any difference with the antenna being retracted all the way (which is more in line with the resonant length) compared to being fully extended?
I somehow formatted my SD card today while attempting to do a backup (it’s a long story). On the bright side, though, doing that opened the opportunity to install a fresh copy of Raspbian, along with mutability.
On a hot day, the Raspberry usually maxes out at 70 C with the fan running. As of yet, haven’t experienced any issues with condensation, however, during the winter I’m sure something will pop up. The antenna works fine outside, it hasn’t been blown over by winds and isn’t affected much by sunlight. I’ve experimented with the antenna being retracted, and actually have experienced a drop in performance.
If enough people are interested, I’ll be willing to share my “polished” web interface. Really though, it’s just a simple HTML landing page.
Hi all,
A brief description of my setup (Site 2508) just south of Eindhoven, The Netherlands:
Antenna: 8 el collinear at 12m AGL
Preamp: G4DDK (35dB gain, NF 0,4 dB)
Filter: 3 pole interdigital
Dongle: R820T2 based
Raspberry Pi2, MLAT enabled.
Test setup (Site 4654):
Antenna: Indoor log periodic at 9m AGL
Dongle: R820T based
Raspberry Pi B, MLAT enabled.
. Interesting fact: the vent acts as a ground plane for the antenna, so I get somewhat improved reception from it.