Airspy R2 for aviation monitoring

[kb5udf]

I live only 0.8 miles form an FM broadcaster with no big problem though I do use an FM broadcast filter. Gain set too high?

I don’t think so, my gain is calibrated so I can hear an air traffic control frequency at low height a few miles away (useful reference) as well as tuning the brazilian pirates on UFO sats. I don’t really listen to either of these much, but both serve as a practical metric of if my listening post is doing well on weak signals.

Everyone’s listening environment is different and although my FM broadcasters are slightly further than you, I have several to contend with. Also, being near the gulf and its humid air, we get a fair number of tropo band openings as well that can pipe in distant signals at local/nearby levels. Additionally, it is possible your broadcast filter is better than mine. I have a stridsberg unit, but perhaps someone like mini-circuits has one with greater attenuation.

In any event, with these filters, my airspy performance is commendable (I can receive fighters training in the gulf about 300 mi away if over 30k feet), which I think is pretty good for a $150 receiver connected to an pre-amped 8 port splitter (sirio 100mhz + discone at 30 feet).

 

[dlwtrunked]

I don’t think so, my gain is calibrated so I can hear an air traffic control frequency at low height a few miles away (useful reference) as well as tuning the brazilian pirates on UFO sats. I don’t really listen to either of these much, but both serve as a practical metric of if my listening post is doing well on weak signals.

Everyone’s listening environment is different and although my FM broadcasters are slightly further than you, I have several to contend with. Also, being near the gulf and its humid air, we get a fair number of tropo band openings as well that can pipe in distant signals at local/nearby levels. Additionally, it is possible your broadcast filter is better than mine. I have a stridsberg unit, but perhaps someone like mini-circuits has one with greater attenuation.

In any event, with these filters, my airspy performance is commendable (I can receive fighters training in the gulf about 300 mi away if over 30k feet), which I think is pretty good for a $150 receiver connected to an pre-amped 8 port splitter (sirio 100mhz + discone at 30 feet).

I do you a much better FM broadcast filter. Although I have a Stridsburg and other FM broadcast filters, when needed, I only use the superior Mini-circuits ZBSF-95-N+. It is not cheap though (~$126) . Indeed the Airspy R2 is an excellent receiver at at nice price. I have an ICOM R9500 and R8600 but usually use the Airspy.

 

[kb5udf]

I may give that a look thanks.

 

[RichM]

I recently dipped my toe into SDR, starting with an Airspy R2. My interest is mostly in aviation monitoring and SDR seems the way to be going, but I admit there has been a bit of a learning curve for me. So far, I have gotten it working well with SDRSharp and Frequency Scanner Plugin on the civil side of things and getting good reception down in the 118-136, but it seems absolutely deaf on 225-400. If I plug the antenna into a BC9000xlt next to the R2 I'll hear tons coming through on 225-400 very clear, but the R2 is missing 100% of it. I am using the same bandwidth of 12,000 and step size of 25,000 for both ranges along with the same gain settings. I have tried the setup at both my home in metro KC and at another remote location with low RF noise with the exact same results. Any ideas of what I might be doing wrong?
thanks,
Gregg in KC

In the Frequency Scanner plug in - what is your “detect” setting at? Higher number = slower scan times but less skipping over active signals. Try around 100 to see if that helps. You also need to set the yellow line in the bottom window just above the noise floor, that works as your squelch. And make sure squelch is “off” in SDR#. Set the red bar just below your active signals. Read the Frequency Scanner instructions to better understand these settings.

 

[RichM]

I’m using an Airspy Mini but these are my source settings in SDR# v1700:
*free
IF gain 13
mixer gain 14
LNA gain 6
sample rate 6 MSPS
decimation NONE
*tracking filter
PPM 0

I had the same issues you describe (CivAir good MilAir not) and this is what works for me. I had many problems with SDR# newer versions (I use an older computer), perhaps try v1700 as it has been rock solid with the Frequency Scanner plug in. I now get MilAir band scan times under 2 seconds (detect @ 40) and only skip past very weak signals that my hardware scanner shows 1 bar on sharing the same antenna. Hope this helps.