Airspy R2 RF Out (Loop)

FlightAware ADS-B Flight Tracking
1

So, at the moment I have 2 feeders running off one aerial using a mini circuits splitter. After getting a Airspy R2 a while back I noticed it had a “RF Out” (loop). Thinking that I could eliminate the splitter (and hence maybe some signal loss) I got a cable off amazon with the required connection for it on one end, and SMA on the other.

Yesterday I removed the splitter, connected the aerial directly into the R2, and then linked the other feeder (that happens to be a Airspy Mini) via the RF Out.

As below, the results for the feeder attached via the RF Out was poor. Messages was down to about 1000 (should have been about 2500), and aircraft about 80 (should have been about 250).

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For comparison, here is the R2.

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Not sure if anyone else uses the RF out of the R2 (or even if it’s meant to be used in this way), but 1). It seems to degrade the signal a lot, and 2). Though hard to tell, I can’t see any real difference with the splitter out of the equation anyway.

2

I’ve not tried it on my R2 but looking at the data-sheet for the R820T2, the RF out is after the variable gain LNA.
Depending on your gain settings it could be that your loop output is at a lower level than the primary RF input to the R2.
Here I use Antenna - Filtered LNA - splitter - SDR receivers.