Any idea if the performance of the Mode S Beast is on par with Radarcape? The latter one is almost 3 times as expensive as the cheaper sibling, why the huge price difference, is that just for the additional gps receiver?
Itās the same device minus a builtin mini-computer and signal path integrated GPS receiver.
Edit: Seems it might not be the same layout.
But you canāt do antenna diversity with the ModeS Beast.
(At least they donāt build it like that anymore i believe, the board layout has the capability. My guess they want you to pay for the Radarcape if you require that special capability)
Both devices might benefit from an LNA unless you are literally at an airport and want to receive those aircraft.
Using the rtl-sdr LNA, youād have to attenuate the signal probably to reduce the gain it has to maybe 10 or 15 dB.
I have both. Both need an amp, despite what they say.
The radarcape is much better than the Mode S beast.
Now thatās strange i read somewhere that the Radarcape is based on the ModeS Beast layout.
The radarcape is based on the Mode S Beast. Not sure that much development has been done on the Mode S Beast to keep it up to date.
That might be the difference you see, but one can only speculate.
Well there need to be budget options! 
Most of hobbyists / feeders use budget equipment:
DVB-T (or ProStick) + RPi.
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The dual receiver of this thread is completely different from Radarcapeās dual antenna system.
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Indeed. For me, āperfectionā will have arrived with the eMMC version of the RPi.
I knowā¦ there are eMMC SBCs out there, but Iām a ādumbā user. I need the support of a widely used platform.
I like hardware integration, not software development.
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I find that both Radarcape and Mode S Beast are quite expensive for devices that entered the market in 2013 and 2011 respectively with the latest firmware version dating back a couple of years. Iāve read somewhere that a German company recently came up with an ADS-B Pi-hat would outperform the FA-dongle, maybe Wiedehopf can elaborate on this matter?
Iāve heard of it, but i donāt think itās quite ready yet
At the moment, whatās stopping you from getting an Airspy?
Or you could make a non-mlat station combined from two receivers.
Would just need to figure out how to mount the antennas so each only covers half of the sky.
Also while combining the data, you could maybe feed one into the combining dump1090 as AVR.
That way it loses its timestamp.
Not sure if the fa-mlat-client could still handle that.
I should do a test for that.
Too bad you canāt just change the command line for the fa-mlat-client input
That would make it easy to run multiple receivers with only one of them being used for mlat.
Iām not sure how you would build antennas to divide the sky into sectors though.
For covering half of the sky with each antenna youād need to somehow have a maybe metal separator?
Something that absorbs 1090 MHz would probably be easiest instead of reflecting it.
I suppose corrugated metal might disperse it enough not to bother the antenna.
Building directional antennas isnāt that good because iād want to completely eliminate the reception from half of the sky.
Due to my favourable location my feeder covers the airspace between London, Paris, Brussels, Amsterdam and Frankfurt so my orange FA dongle has to swallow quite some traffic. More than 250 planes in the air and 1300 msg/s is no exception so statistically Iām not doing too bad ranking just outside the top 100 flight feeders. Iāve been tampering with the RF gain to maximize the throughput but I always end up with either losing long range or overhead traffic, it seems that the 8 bit ADC of the RT820 is the limiting factor for the dynamic range I would like to obtain. I already have a better SDR, the RSP2 from SDRPlay but I believe itās not really compatible with dump1090 so I prefer to use it for other purposes. Maybe I should give the Airspy R2 a try, I guess that itāll need a preamp as well?
There is at least one fork of dump1090 that should work with the SDRPlay: GitHub - SDRplay/dump1090: Version of dump1090 for RSP devices
No idea what the quality or performance is like.
In regards to ADS-B the Airspy Mini does just as well as the R2, and itās quite a bit cheaper.
I would recommend getting a RPi 4 so you have enough CPU to use the 20 MHz sample rate instead of 12 MHz.
Yes it needs a preamp, as i wrote previously my prime choice is the rtl-sdr LNA.
Iād recommend going with an external bias-t, that way you can experiment which voltage from 3 to 5 V works best for you
Thanks for the advice.
Just ordered an Airspy mini and an rtl-sdr LNA, guess the RPi4/2GB that I bought last week will be sufficient.
Sure it will be
You probably already have a bias-t.
While the airspy will supply the rlt-sdr LNA, i would recommend getting an external bias-t like this one (Bias Tee Wideband 1mhz-3ghz for Ham Radio RTL SDR LNA Low Noise Amplifier 50vdc for sale online | eBay)
Also for the Pi4 and also the Airspy Mini, a fan doesnāt hurt to keep them a little cooler.
This one seems to work pretty well and is easy to install Fan SHIM for Raspberry Pi
But as youāve probably seen in my pictures i just used a 12 cm 12 V fan, connected it to my 5 V supply and hung it so it moves air over the whole contraption i use
There are also other fan options for the RPi4 of couse, but it basically needs a fan.
I have a couple of bias-tās laying around but none of them have sma-connectors so Iāll order the one you mentioned.
I went through the Airspy topic (at high speed) but it never mentions the Pi4 (always 3B+ or Odroid) or did I miss something?
Not too many people have tried and none of them mentioned it in that thread.
@bramjacobse has it running though.
Also the pi4 is much faster than the pi3b+, and even on that it is under the right conditions possible to run 20 MHz.
