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Assorted ramblings from the developer

RadFxSat Fox 1B
RadFxSat Fox 1B

Picking up RadFxSat Fox 1B on her first pass over Cornwall, FM on 145.960 adjusted for Doppler. The initial TLE data is pretty accurate. Receiver is the Airspy HF+, antenna general log periodic for 130 MHz to 1.3 GHz.


Click here for an audio recording (MP3)

Station Info

V3 Analyser
V3 Analyser

Here's a screenshot of the version 3 Analyser slowly taking shape. This is a zoomed processing on 963kHz taken from an overnight recording, we see many medium wave (MW) carriers present.

Data processing at 1,343 megabytes / second from a NVMe SSD card.

More later...

In The Shack

Here are pictures of the offcie / playroom / shack.



Airspy HF+ & NOAA 18
Airspy HF+ & NOAA 18

Overhead Pass

Here's an example of the HF+ receiving the NOAA 18 APT weather satellite, the antenna is a log periodic covering 130 MHz to 1.3 GHz. The HF+ is very sensitive and very quiet - no mixer products, spurs, or artifacts at all.



Low Angle Pass

Here's an image from NOAA 18 but a moch lower angle - 13 degrees. You see noise on the image, but nethertheless an excellent copy.

CW Skimmer

The original CW Skimmer implementation missed an importrant feature, namely:

* Working properly

After a few hours' coding it's now OK.

V3 Demo

Amateur radio operators on 80m. Recorded using a NetSDR and Wellbrook loop antenna.

ML&S, RSGB Convention 2017
ML&S, RSGB Convention 2017

Good to see SDRs being demonstrated at the 2017 RSGB convention, just wish I were there. Photo from a post on the ML&S facebook page.


Keyclicks on 20m

Lots of keyclicks on 20m!

Recent Posts

  • 3.0 Released Posted 2 days ago
    Version 3.0 was started on February 28th, 2015 at 07:43. Many hours of coding later and I'm able to release 3.0. Check this blog for the status of 3.01, new features, fixes etc. Download here. 73, Simon
  • FM Band II E's & Tropo Posted 3 weeks ago
    The band is filled with lots of French, Spanish and Moroccan stations, a mix of Tropo and Sporadic-E. Using Airspy R2 and 8-element yagi from Innov Antennas.
  • Direct Frequency Input Posted 3 months ago
    You now enter a new receive frequency by simply entering 0 ... 9 or . (period). As soon as you start typing the Frequency window is displayed. C toggles the Centre option, K toggles between kilohertz and megahertz. For more options click the ellipses.
  • Signal History Export Posted 3 months ago
    The signal history is selected from the View, Spectrum pane in the ribbon bar, the data is exported by selecting the ellipses button. In the Export window you now select: Field delimiter and correcsponding file format of comma (CSV) or tab (TSV), Decimal separator of . or the separator for your locale, for example a ,.
  • Broadcast FM Posted 3 months ago
    At the request of Broadcast FM users, I've added the most common options to the ribbon bar. The image below shows what's now. Stereo - enables stereo, when signals are weak mono can be preferable, Partial - enable display of text even when only partially decoded, should be used in very weak signal situations, PI Code - show the Program Information code, Show - show the RDS text in an overlay on the waterfall.
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