SP5LOT DVB-S2 decoder and MX Uploader (SkyEdge) 1.0.2

Windows receiver and decoder for DVB-S2 transmissions (RTL-SDR or HackRF One) with SSDV photos and upload to the SkyEdge MX merger; one of its uses is video from high-altitude balloons. MX Uploader, for stations that receive with another decoder, is a separate program in this release.

New in 1.0.2: better reception of a weak or noisy signal

• With a weak signal, 1.0.1 could show FRAMELOCK and a good MER and still produce no video until the signal faded away. The demodulator in 1.0.2 recovers from this by itself and decodes noticeably more from weak recordings. With a good signal nothing changes.
• Known limit: in AUTO mode a very weak transmission with a low MODCOD (QPSK 1/4 to 1/2) may be treated as noise. The SkyEdge transmitter uses QPSK 3/4 and is not affected.
• GUI unchanged. MX Uploader: no changes, only the version number.
• 2 October 2026: the receiver ZIP no longer contains MX Uploader, which has its own ZIPs (program and source). The programs themselves are unchanged.

Inside the receiver, the DVB-S2 demodulator is leandvb from leansdr by pabr, and the LDPC decoder is ldpc_tool by Ahmet Inan (adapted by pabr), both with our patches. This is an unofficial program, not affiliated with the leansdr author: please report problems here, not upstream.

Download: extract all files of the receiver ZIP into one folder and run leandvb_gui.exe; MX Uploader is mx_uploader.exe from its own ZIP. How to use them: the README on the main page (also README.txt in the ZIPs). Updating from 1.0.1 or 1.0.0: extract the new ZIP into a new folder and copy leandvb_gui_settings.ini (and mx_uploader.ini) from the old folder to keep your settings.

File	What it is	SHA-256
SP5LOT-dvbs2-decoder-1.0.2-win64.zip	receiver 1.0.2 (build 46)	2ad6c1900620460de1ced72e3899ba74d992951354a67a9af0905165d4d27aa9
SP5LOT-mx-uploader-1.0.2-win64.zip	MX Uploader 1.0.2 (build 12), a separate program for stations that receive with another decoder	e1dc250b888eb4b35286d93ab51067247a18cfeea77e199017afa2e0f9dc7706
SP5LOT-dvbs2-sample-iq.zip	sample IQ recording to try decoding from a file	d1495e47bbfe8029cdffd276776d83ff2eba11873da7e93f0fa911b10fde3845
SP5LOT-dvbs2-decoder-1.0.2-source.zip	source code of the receiver, our engine patches and BUILDING.md	6a0e75f7dc1a6967ed9c49cc85aef8d3d01a157dd1161d0a2168405955fd5eda
SP5LOT-mx-uploader-1.0.2-source.zip	source code of MX Uploader and BUILDING.md	feeb6e973bcdcd083e9996b7899af8c4f85d924b9b44c0afaf98ae4fb1eefb7a

The automatic Source code (zip / tar.gz) archives of GitHub contain only the files of the main page (README, license).
The source code of the programs is in the two -source.zip files.

Known limitations in 1.0.2: frequency and symbol rate are not remembered, the bundled RTL-SDR library has no support for the RTL-SDR Blog V4 (not tested with a V4), HackRF may rarely need a program restart. Tested on Windows 10. Problems and ideas: please open an issue.

License: GNU GPL v3. Third-party components: THIRD_PARTY.md.

SP5LOT DVB-S2 decoder and MX Uploader (SkyEdge) 1.0.1

Windows receiver for DVB-S2 video from high-altitude balloons (RTL-SDR or HackRF One) with SSDV photos and upload to the SkyEdge MX merger, plus MX Uploader for other decoders.

New in 1.0.1

• Decoding a recorded IQ file: in Source / SDR choose IQ file and pick a recording (SatDump, rtl_sdr, HackRF). The format and the sample rate are read from the file name. How to use it: Decoding a recorded IQ file.
• When decoding a file, the MODCOD is always detected automatically (AUTO), so a recording made with another MODCOD decodes too.
• When decoding a file, nothing is sent to the MX merger (no connection at all), even with Upload to MX server ticked. Live reception with RTL-SDR or HackRF works as in 1.0.0.
• Sample recording SP5LOT-dvbs2-sample-iq.zip: 19.5 s of a real signal (QPSK 3/4, 500000 symbols/s, 2.048 MS/s) to try it.
• MX Uploader: no changes, only the version number.

Inside the receiver, the DVB-S2 demodulator is leandvb from leansdr by pabr, and the LDPC decoder is ldpc_tool by Ahmet Inan (adapted by pabr), both with our patches. This is an unofficial program, not affiliated with the leansdr author: please report problems here, not upstream.

Download: extract all files of the ZIP into one folder and run leandvb_gui.exe (receiver) or mx_uploader.exe (MX Uploader). How to use them: the README on the main page (also README.txt in the ZIPs). Updating from 1.0.0: extract the new ZIP into a new folder and copy leandvb_gui_settings.ini (and mx_uploader.ini) from the old folder to keep your settings.

File	What it is	SHA-256
SP5LOT-dvbs2-decoder-1.0.1-win64.zip	receiver 1.0.1 (build 45) and MX Uploader 1.0.1 (build 11), all in one	2e195a3de3f765074b3966d7735b99dead4cd71d7913a8c07f93a9e3b23765ca
SP5LOT-mx-uploader-1.0.1-win64.zip	only MX Uploader 1.0.1 (build 11), for stations that receive with another decoder	f6ff2ee7eba05cbd2e6507aa99ad04dac7231bd1e6f37d0f09284b519bda828e
SP5LOT-dvbs2-sample-iq.zip	sample IQ recording to try decoding from a file	d1495e47bbfe8029cdffd276776d83ff2eba11873da7e93f0fa911b10fde3845
SP5LOT-dvbs2-decoder-1.0.1-source.zip	full source code, our engine patches and BUILDING.md	d7c4f10886cf2eafed0fdb4677f66c63747a2293c2c89ce1389e999df90f00d5

The automatic Source code (zip / tar.gz) archives of GitHub contain only the files of the main page (README, license).
The source code of the programs is SP5LOT-dvbs2-decoder-1.0.1-source.zip.

Known limitations in 1.0.1: frequency and symbol rate are not remembered, the bundled RTL-SDR library has no support for the RTL-SDR Blog V4 (not tested with a V4), HackRF may rarely need a program restart. Tested on Windows 10. Problems and ideas: please open an issue.

License: GNU GPL v3. Third-party components: THIRD_PARTY.md.

SP5LOT DVB-S2 decoder and MX Uploader (SkyEdge) 1.0.0

Windows receiver for DVB-S2 video from high-altitude balloons (RTL-SDR or HackRF One) with SSDV photos and upload to the SkyEdge MX merger, plus MX Uploader for other decoders.

Inside the receiver, the DVB-S2 demodulator is leandvb from leansdr by pabr, and the LDPC decoder is ldpc_tool by Ahmet Inan (adapted by pabr), both with our patches. This is an unofficial program, not affiliated with the leansdr author: please report problems here, not upstream.

Download: extract all files of the ZIP into one folder and run leandvb_gui.exe (receiver) or mx_uploader.exe (MX Uploader). How to use them: the README on the main page (also README.txt in the ZIPs).

File	What it is	SHA-256
SP5LOT-dvbs2-decoder-1.0.0-win64.zip	receiver 1.0.0 (build 44) and MX Uploader 1.0.0 (build 10), all in one	6e5af31940790cd81cc33cffa5f26c4825143883e872e99298c64dbf93d1b2cf
SP5LOT-mx-uploader-1.0.0-win64.zip	only MX Uploader 1.0.0 (build 10), for stations that receive with another decoder	7ed5730f3736d9bf4c7468ec62908f7d71dfef3edd29fffc22999526ad863a73
SP5LOT-dvbs2-decoder-1.0.0-source.zip	full source code, our engine patches and BUILDING.md	7da6f25c420b79b3ddbf36097c2cc404a0d221bea6a032a71a03571514c4a2ab

The automatic Source code (zip / tar.gz) archives of GitHub contain only the files of the main page (README, license).
The source code of the programs is SP5LOT-dvbs2-decoder-1.0.0-source.zip.

Known limitations in 1.0.0: frequency and symbol rate are not remembered, the bundled RTL-SDR library has no support for the RTL-SDR Blog V4 (not tested with a V4), HackRF may rarely need a program restart. Tested on Windows 10. Problems and ideas: please open an issue.

License: GNU GPL v3. Third-party components: THIRD_PARTY.md.