Tagged: airspy

Airspy GNU Radio Script for Receiving LRPT Meteor-M2 Weather Satellite Images

Previously we posted about receiving LRPT weather satellite images from the Russian Meteor-M2 weather satellite using the RTL-SDR. Now on GitHub, developer otti-soft has uploaded a LRPT decoder GNU Radio script for the Airspy. The script appears to be a modified version of the GNU Radio based real time decoder for the RTL-SDR, but optimized for the Airpsy and it’s 10 MSPS or 2.5 MSPS sampling rates. Note that although this is a real time receiver, the final image still needs to be processed on a Windows PC using LRPToffLineDecoder.

Also over on Twitter otti-soft has been uploading some images that he has received with his Airspy.

Real time LRPT Receiver for the Airspt
Real time LRPT Receiver for the Airspy

Screening Mods for the Airspy

The programmer of Linrad, Leif (sm5bsz) has recently been experimenting with some modifications to the Airspy metal case. He discovered that the USB and RF input connections on the Airspy were not making good electrical connections to the metal case because of the paint on the case. These bad connections caused interfering broadcast FM to be received by the Airspy through the USB cable even when the antenna input was terminated with a dummy load. By sanding down the paint on the metal box to improve the connection he was able to significantly reduce the interference. He writes:

It is a good idea to make sure that both the SMA connector and the USB screen have a good electrical contact with the box. Grounding only the USB screen causes a severe degradation of the NF.

The findings here may also be useful for improving shielded RTL-SDR dongles.

http://www.youtube.com/watch?v=fXGMEdeGkbg

Comparison of several SDRs on degradation from nearby strong signals at broadcast FM frequencies

The programmer of Linrad (aka Leif sm5bsz) has uploaded a video to YouTube that compares several software defined radios on dynamic range and compression performance in the presence of strong nearby signals. In the video Leif tests the Airspy, BladeRF with B200, FDM-S1, Funcube Pro+, rtlsdr/E4000, rtlsdr/FC0013, rtlsdr/R820T, SDR-14 and SDRplay.

The main test works by tuning to a broadcast band FM frequency and then injecting a strong carrier signal at distances of 500 kHz, 1 MHz, 2 MHz and 5 MHz from the center frequency. The carrier signal strength is slowly increased until the SDR shows signs of complete degradation of reception of the FM signal. Better SDRs will tolerate stronger nearby signals without degradation.

The results are summarized at 34:20, 1:21:38 and 1:48:30. We have also taken screencaps of the results at 1:21:38 and 1:48:30 and they are shown below. The first column is when a higher gain is used, and the second column is when a lower but still barely copyable gain level is used. In the Levels for loss of performance columns smaller numbers are better and in the Dynamic range columns larger numbers are better. Finally, at the end of the video starting at 1:45:55 Leif also tests the spur performance of the SDRs.

Results at 500 kHz and 1 MHz Seperation
Results at 500 kHz and 1 MHz Seperation
results_3
Results at 2 MHz and 5 MHz Seperation
SDR on 88-108 FM part1

Airspy Vs RTL-SDR on VLF and Broadcast FM

Over on YouTube user Mile Kokotov has uploaded two videos showing a comparison between the Airspy and RTL-SDR software defined radios. The Airspy is a high performance SDR that costs $199 USD.

The first video shows a comparison between the two SDR’s and two hardware radios on receiving a very weak broadcast FM station amongst several very strong ones. Mile first tested his hardware radios and found that his Onkyo radio was able to clearly receive the weak station, whilst his Pioneer radio could not at all. Then he tested his SDR’s and found that his Airspy was able to receive the station, but the RTL-SDR could not and suffered from intermodulation when the gain was turned up because of the nearby strong stations. This shows how the 12-bit Airspy ADC vs the 8-bit ADC on the RTL-SDR can make a difference.

The second video shows a comparison between the RTL-SDR and Airspy on a VLF time signal at 60 kHz using a ham-it-up upconverter. His video shows that the Airspy signal is about 8dB stronger the the RTL-SDR.

http://www.youtube.com/watch?v=OgU7Gv3lca8#t=118

Airspy vs RTL SDR receiving VLF

Airspy Second Batch of Preorders Available

The Airspy software defined radio recently completed its first round of 400 pre-orders. Now the second round of pre-orders has become available over on the manufacturers web store. It is priced at $199 USD and they expect the orders to be shipped around the middle of December.

If you were unaware the Airspy is an RX only SDR developed by the author of the SDR# software. It has a tuning range of 24 MHz to 1.7 GHz, up to 10 MHz of instantaneous bandwidth and a 12-bit ADC. The full list of features is shown below.

  • Continuous 24 – 1750 MHz RX range with no gaps
  • 3.5 dB NF between 42 and 1002 MHz
  • Tracking RF filters
  • 35dBm IIP3 RF front end
  • 12bit ADC @ 20 MSPS (80dB Dynamic Range, 64dB SNR, 10.4 ENOB) – Yeah, size does matter.
  • Up to 80 MSPS for custom applications
  • Cortex M4F @ up to 204MHz with Multi Core support (dual M0)
  • 1.5 ppm high precision, low phase noise clock
  • 1 RTC clock (for packet time-stamping)
  • External clock input (10 MHz to 100 MHz via MCX connector) – Ideal for phase coherent radios
  • 10 MHz panoramic spectrum view with 9MHz alias/image free
  • IQ or Real, 16bit fixed or 32bit float output streams
  • No IQ imbalance, DC offset or 1/F noise at the center of the spectrum that plagues all the other SDRs
  • Extension ports: 16 x SGPIO
  • 1 x RF Input (SMA)
  • 1 x RF Output (Loopthrough, U-FL)
  • 2 x High Speed ADC inputs (up to 80 MSPS, U-FL)
  • 4.5v software switched Bias-Tee to power LNA’s and up/down-converters

The Airspy was recently reviewed in two videos by W9RAN, the second video showing some sensitivity measurements. There are also various other videos of the Airspy in action now on YouTube.

Airspy Software Defined Radio
Airspy Software Defined Radio

Airspy Sensitivity Measurements and HF Performance

Over on YouTube user ranickel (aka W9RAN) has uploaded a video discussing and reviewing the sensitivity of the Airspy software defined radio. In the video he uses a signal generator to generate a reference signal and shows what the effect of software decimation has on the signal to noise ratio. His results show that the Airspy is a very sensitive and low noise receiver that is comparable to some very expensive hardware.

Airspy Sensitivity Measurement by W9RAN

In another new video W9RAN shows a quick sneak peak at the performance of the Airspy on the 20 meter CW band when using a prototype HF upconverter that he is developing.

Airspy HF Converter Sneak Peek by W9RAN

YouTube Airspy Review and Comparison

Over on YouTube user ranickel (aka W9RAN) has uploaded a video showing his review of the Airpsy software defined radio. Although the Airspy is not yet shipping, several independent reviewers received a unit early.

In the video W9RAN compares the Airspy against seven traditional analogue hardware radios and the RTL-SDR using a amateur radio beacon at 28 MHz. He also demonstrates the software decimation feature of the Airspy drivers and shows how it can increase the sensitivity and signal to noise ratio.

Airspy Review and Comparison by W9RAN

Airspy Now Available for Pre-Order (Shipping Mid November)

The long awaited Airspy software defined radio is now available for preorder and will ship during mid November for those orders placed before November 7. It is priced at $199 USD.

The Airspy is an RX only SDR with a tuning range of 24 MHz to 1.7 GHz, up to 10 MHz of instantaneous bandwidth and a 12-bit ADC. The full list of features is shown below. If you are looking for an upgrade to the RTL-SDR and do not need TX capabilities, this is probably the SDR that will provide the best performance for price.

  • Continuous 24 – 1750 MHz RX range with no gaps
  • 3.5 dB NF between 42 and 1002 MHz
  • Tracking RF filters
  • 35dBm IIP3 RF front end
  • 12bit ADC @ 20 MSPS (80dB Dynamic Range, 64dB SNR, 10.4 ENOB) – Yeah, size does matter.
  • Up to 80 MSPS for custom applications
  • Cortex M4F @ up to 204MHz with Multi Core support (dual M0)
  • 1.5 ppm high precision, low phase noise clock
  • 1 RTC clock (for packet time-stamping)
  • External clock input (10 MHz to 100 MHz via MCX connector) – Ideal for phase coherent radios
  • 10 MHz panoramic spectrum view with 9MHz alias/image free
  • IQ or Real, 16bit fixed or 32bit float output streams
  • No IQ imbalance, DC offset or 1/F noise at the center of the spectrum that plagues all the other SDRs
  • Extension ports: 16 x SGPIO
  • 1 x RF Input (SMA)
  • 1 x RF Output (Loopthrough, U-FL)
  • 2 x High Speed ADC inputs (up to 80 MSPS, U-FL)
  • 4.5v software switched Bias-Tee to power LNA’s and up/down-converters

See our big comparison list of other SDRs here.

Airspy Software Defined Radio
Airspy Software Defined Radio