FlightAware Discussions

Every day my receiver gets overloaded

Exactly, is that the one you got? The picture you posted shows a wideband LNA, without the triple filter design. The wideband LNA will not make it any better if you have a lot of cellphone activity that will overload the reciever.
What you experience is probably related to the traffic between cellphones and transmitters. The more cellphones that are active in the area where your antenna and reiciever are located, the less airplanes you see due to increased activity on the 3- and 4G cellphone frequencies. It’s like trying to hear someone whisper 30 meters away from you at a rock concert.

THAT makes sense. OK, now I’m the idiot. I’ve ordered the wrong device. Will order the correct one.

I still have the light blue filter from flightaware. I could use this for the moment. Does that makes sense?

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Better than nothing. Too bad about the device but good that you took a snapshot :slight_smile:

I guess I will have to look up my old ebay account and sell it. :tired_face:

hello bdcinside, i started this “hobby” last july. for 10 months now i have been building a growing pile of “oops, the wrong device/connector/adaptor/etc”. so, you can put your wideband LNA in a box and begin your own “oops” pile. in the meantime, adding the blue filter from flightaware will be a good experiment. i would be interested in wiedehopf’s comments, but i would put the blue filter before the LNA, that way you won’t be amplifying EVERYTHING, just the signals in the passband of the filter.

Yes, that’s the way I did it. A 10m scan is running right now. The “oops-box” I do already have.

8 years ago I moved to my flat right 2.5km off EDDB. Since then I’ve learned a lot about air crafts, air lines just because I can see them flying by my roofgarden. I’m excited about learning handling a linux system and that is what I have hoped for. Within one year my computing environment changed to a linux based one. Just have a single Windows device left. Never imagined that this could happen with me :wink:

Learning about physics, making mistakes and discover things is great. The journey is the reward.

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Yes, that makes sense (and probably an improvement of the current situation).
Most of us have made similar mistakes, it’s part of the process of learning and improving :wink:

You will get the best effect of the (new) LNA if you place it as close to the antenna as possible. Directly at the antenna via a short lead (pigtail), mounted with a N-to-SMA adaptor or with a short (1m) cable and then the longer cable from the LNA to the reciever. That will improve the system as a whole compared to having a long cable between the antenna and LNA. But it requires a weather proof box or similar since the LNA isn’t made for outdoor mounting without a protective box or similar.

Thx for your words an advices. :grinning: I’ve already thought about installing it outdoors. But regarding LAN, rain&sun, power supply there are many things to consider.

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I have the LNA (and lightning protection) in a waterproof box with a 1m cable from the antenna. Then a run of 5 meters of cable (through an unused pipe in the chimney :grimacing:) and finally the airspy mini and an Intel NUC placed indoors.
The lightning protector is perhaps not needed since we have very few lightning storms here (2-3 per year and very timid ones compared to the ones in southern Sweden and the European continent). I’m sure that if I didn’t have it, I would have multiple lightning strikes in the antenna every year :grin:

I do not find a working gain level. Just having around 5 to 20 Messages/sec.

Went back to FA Pro + Dongle and using the additional filter. Will observe this one. Good night from Berlin!

Will read your comments tommorrow…

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Your receiver is probably overloaded due to the strong cellphone signals that your scans show. And the filter is not dampening the out-of-band-signals enough. Had the same problem here…

I thought that people living in Berlin never went to bed before 5 in the morning :laughing: I know that I never did when I spent a week there in 1988 :crazy_face:

Good night from the vasts forests of rural Sweden :slight_smile:

True words. I have a good view on at least 7 different buildings around with some big antennas on it. Waiting for my LNA…

Btw 1400:

At 1640 I restartet pi1. Reception was better than ever.

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That’s really strange. Any strange lines in syslog that could indicate that the Pi isn’t working properly?
Something makes your system (PI and dongle) work worse at 1400 hrs. If it was something in the air the dongle should recover when the disturbance disappears, not after a reboot (unless the disturbance is so powerfull that it somehow “crashes” the dongle, but that sounds (to me) quite unlikely).

Perhaps something in your local electrical grid causes a spike (or drop) that affects the PI in a bad way.
You don’t happen to have an UPS with proper filtering of the incoming electricity that you can connect the PI to? It’s a far-fetched theory, but stranger things have happened :slight_smile:

I wonder if it’s a problem with the LNA in the prostick plus.

I’d recommend just using the rtl-sdr v3 dongle with the filter you have.

You might want to update your graph version from adsb-receiver, the newest version properly displays the “strong messages” (in red).

Talking with my wife about building a flight receiver isn’t a good idea at all. BUT yesterday she asked me since when the problems occur. Then she asked me to look into the orders I’ve made via Amazon in that time. And there we are: I’ve order a Nvidea Shield (Android TV) and a SAT>IP-Receiver.

This morning I simply switched off the Sat>IP-Receiver. Instantly the message rate was increasing from 30/s to 600/s and above. Wow!

dump1090-localhost-signal-6h dump1090-localhost-aircraft-6h

I switched it on again after 8 o’clock. I’m stunned by this effect!

The coax cables for my sat dish are partly running the same way as the cable for my antenne. The window coax cable runs very close to the other window coax cables. The Receiver is mounted in a distance of 3.5m from my antenna.

I guess I have to figure out how to seperate these two systems from each other or how to prevent these interferences.

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This will be a big part of the problem, those are not made for GHz frequencies.

But if you can’t work without them, running them as far apart from each other as possible will be very useful.
That would be the first change i would try.

Then switching it off when you are not using it seems like a good idea :slight_smile:
(Not very comfortable though.)

Depending on the frequency of noise it produces the filtered rtl-sdr LNA will also help a great deal.
You should probably figure out how to weather proof it and place it at the antenna.
That would mean the loss from the window coax won’t reduce performance as much.
Also the signal should be strong enough that the noise doesn’t hurt it that bad.
(Especially when you put some distance between both window coax cables)

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Yes, right. Many things to be done when the LNA arrives. Because I cannot switch off the sat ip receiver, I decided to wrapped some aluminium foil around the windows coax. Nothing happend. After that I wrapped some foil around the connectors between coax/filter and between filter/wideband amp and between amp/dongle. My reception improved drastically. Let’s wait and see if this prevents the “1400”.

dump1090-localhost-aircraft-6h%20(2)

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If that makes a difference then either the cable or connector is seriously defective.
(or the connectors aren’t connected correctly)

Maybe the pin didn’t go in properly? It can be quite tricky.
If you are sure it is aligned correctly try tightening it more.
(hand tight should suffice but don’t be gentle, using a wrench on the other hand you can easily overdo it.)

Also would be useful if you update the adsb receiver graphs or use my version of the graphs, in both i’ve fixed the “strong messages” (graph in red)
(https://github.com/wiedehopf/graphs1090#graphs1090)

Then you can more easily set a sensible amount of gain.

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I will review the adapters after installing the lna. Now that I know that my sat-ip-receivers is the reason for the “1400” I’ve looked into my thvheadend config. I discovered that the epg over the air grabber is configured to do a scan at 2 am and 2 pm. That triggers the activity on the sat-ip-receiver. That fit’s :smiley:

image

Will change for testing…

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Short update. Received my LNA. Plugged in antenna:

LNA doesn’t resolve the interferences from sat-ip receiver. Had to move raspberry and antenna. Thats ok now.

Have to build a outdoor receiver now. Read a lot about it. Will go for a metal box and try to build a system with sufficient cooling.

Have Good night!

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