Category: Satellite

OrbitNight: A Free Browser-Based Satellite Pass Viewer with Antenna Rotator Control via Web Serial

Thank you to the OrbitNight team for writing in and sharing their "OrbitNight satellite radar", a free browser-based pass viewer for any satellite in the catalog. It can also point an antenna rotator straight from the browser over USB using Web Serial, so you don't need to install anything.

The radar page shows a polar plot of the pass track, live azimuth and elevation readouts, and an AOS/LOS countdown. A radio tab lists downlink and uplink frequencies taken from SatNOGS. For rotator control, it supports Yaesu GS-232 compatible controllers (including K3NG and ERC) and EasyComm II controllers like those used on SatNOGS stations connected over USB serial, or Bluetooth on Android. It also has an azimuth offset setting and a 1 degree deadband.

The site works in Chrome and Edge on desktop, and rotator control needs a browser that supports Web Serial. It's free and needs no sign-up. The team notes that there is no 450 degree or flip mode yet, and they'd like to hear from anyone who tries it with a real rotator. If you track LEO satellites with a directional antenna and an RTL-SDR, this could be a simpler option than setting up Gpredict and Hamlib. We note, however, that we couldn't find an open-source codebase.

The OrbitNight Live Tracking Page
The OrbitNight Live Tracking Page

Elektro-L3 Arrives at 14.5°W and Begins Testing L-Band LRIT and HRIT

Earlier this month we posted about the Russian Elektro-L3 geostationary weather satellite drifting west from 76°E to 14.5°W. It is replacing Elektro-L2 and could bring unencrypted L-band LRIT and HRIT imagery back to Western Europe. Now tec_msat has written in again to let us know that Elektro-L3 has arrived. It is already transmitting X-band RDAS and testing LRIT and HRIT.

tec_msat notes that the satellite was only active on C-band for a couple of days. Then, on October 26, its RDAS, xRIT, and DCP (Data Collection Platform) downlinks all went up. Elektro-L2's DCP transmission at 1697 MHz was switched off at 06:30 UTC, and L3's DCP came up at 07:02 UTC. LRIT data was being received from about 09:42 UTC. GGAK (space weather data) is still being transmitted from Elektro-L2 for now.

This is the first xRIT from 14.5°W in years, so tec_msat warns that transmissions may be sporadic for a while. It's too early to judge signal strength, but it already looks stronger than L3 did at low elevation (under 15 degrees) in its old slot.

If you're in Western Europe, now is a good time to get your dish ready. SatDump is the best software for reception and decoding, and our Discovery Dish with L-band feed and an RTL-SDR Blog V3 is a great starting point for hardware.

Elektro-L3 LRIT Image Received from 14.5°W on October 26
Elektro-L3 LRIT Image Received from 14.5°W on October 26

DecSAT: A DVB-S/S2/S2X Satellite Receiver with Blind Scanning for the HackRF One

Thank you to RTL-SDR.COM reader Vitor for writing in and sharing DecSAT, an open-source Rust program by CasualArclamp that turns a HackRF One into a DVB-S/S2/S2X satellite receiver. It's laid out like SDR++, with a large waterfall and VFOs that you drop onto carriers, each running its own decoder.

DecSAT decodes DVB-S2 and S2X carriers, including ACM, and outputs MPEG-TS to VLC or its built-in TV player, and IP data to PCAP files for Wireshark. A blind 'Identify' mode works out an unknown carrier's symbol rate and modulation, and a 'Survey' tool acts like a blind scan, identifying and decoding every carrier in the span. It also supports various SCPC modem, voice, radar, and satellite beacon formats.

Portable Windows binaries are available on the original repo's releases page, and Vitor notes that he has created a fork that adds a Visual Studio 2022 build.

Update: Vitor notes that his fork as added several new features, including analogue modes such as WFM with RDS, analogue TV (PAL/NTSC) and integration to CrazyCat's streamreader.dll allowing use of compatible satellite tuners (mostly made by TBS) to setup the LNB (polarity, band and power), launch DiSEqC commands and blindscan and stream the actual TS back to DecSAT. He notes that these updates should eventually work their way back into the upstream code.

DecSAT Identifying Carriers in a Synthetic 8 MS/s Test Scene
DecSAT Identifying Carriers in a Synthetic 8 MS/s Test Scene

AI Disclaimer: Claude is listed as a contributor to the DecSAT repo.

Elektro-L3 Now Drifting West to 14.5°W: L-Band xRIT Could Return to Western Europe in October

Back in May, we posted about how Russia's Elektro-L3 geostationary weather satellite was expected to move from 76°E to 14.5°W, which would finally bring an unencrypted L-band LRIT/HRIT downlink over Western Europe. Thank you to RTL-SDR reader tec_msat for writing in and letting us know that the move now appears to be underway.

tec_msat writes that Elektro-L3 went quiet around September 10. Updated TLEs on September 13 then showed the satellite drifting west at roughly 1.7 degrees per day. Around September 20, its orbit was circularized, making it drift faster at around 3.1 degrees per day. At its current speed, it should reach 14.5°W around October 12. Based on Elektro-L5's commissioning timeline, test transmissions could begin within days of arrival.

Elektro-L5, launched in February 2026, has now been successfully commissioned at L3's old 76°E slot, which covers Asia, the Middle East, and parts of Russia and Australia. It has been transmitting GGAK, LRIT and HRIT, as well as X-band RDAS. With L5 taking over the eastern slot, L3 will replace the aging Elektro-L2 at 14.5°W. L2 never provided LRIT/HRIT from that position due to power supply issues, although the original Elektro-L1 did when it was stationed there.

Roscosmos noted in August, when announcing L5's commissioning, that L3 may be moved to 14.5°W. However, there has been no official announcement from Roscosmos that the relocation has started, so the drift observations currently come from amateur TLE tracking.

Once commissioned, L3 should once again make geostationary L-band weather imagery at 1691 MHz available to users in the UK, Ireland, Iceland, Portugal, Spain and western France. tec_msat also speculates that the signal may be stronger over Europe than it was from 76°E (potentially due to better elevation angles), making xRIT reception even easier.

If you're in the coverage area, now might be a good time to get your dish, feed and LNA ready. SatDump is the best software tool to use for reception and decode and our Discovery Dish with L-Band feed and RTL-SDR Blog V3 is a great starting point for hardware.

Expected Elektro L3/L4/L5 global coverage from mid-October 2026.
Expected Elektro L3/L4/L5 global coverage from mid-October 2026.

InmarScope: An Inmarsat AERO and STD-C Decoder with Multichannel Decoding and Automatic Call Following

Over on the SignalsEverywhere YouTube channel, Sarah Rose has released InmarScope, a multichannel L-band Inmarsat decoder that connects directly to an RTL-SDR, Airspy, or HackRF. The software can receive and decode both aeronautical (AERO) and maritime (STC-C / EGC) traffic at the same time. Decoders are dropped directly onto the aligned FFT and waterfall by holding CTRL and left-clicking, and the software lets you stack Aero MSK (600/1200 bps), high-rate OQPSK (10500 bps), AMBE voice (8400 bps), and Inmarsat-C BPSK decoders side by side.

One of the more interesting features is automatic voice-call following. By monitoring the 10500 baud forward-link channels, InmarScope can receive C channel voice assignments and automatically retune the SDR to the assigned frequency, lock the carrier, decode and record the AMBE call, and then hop back to where it was. There is also a two-SDR mode that dedicates a second radio to voice with a live split-view spectrum so one radio stays on the P control channel while the other tunes to voice calls. For assignments that never get broadcast, there is also a Call Hunter feature that uses a squelch threshold to automatically drop the decoder when a call appears. When a call is playing, the built in flight map also decodes the aircraft hex ICAO address and looks it up on airplanes.live, showing the plane's position and route in real time.

Recent updates have added a community-editable band plan, message search and filtering, an IQ recorder that also captures the seconds before you hit record, and a web dashboard for browsing decoded data from a phone.

The software is completely open source on GitHub, and the C++ code can be compiled from source, or a precompiled Windows build is available on sarasforge.dev for $15, with Sarah's Patreon patrons getting it free.

We note that Inmarsat signals such as AERO and STD-C/EGC can be received with our RTL-SDR Blog L-band Patch Antenna, which is available in our store.

Multi-Channel Voice Following Inmarsat Decoder for Windows!

Decoding Inmarsat in 2026

Receiving US Nuclear Detection Satellite Signals with RTL-SDR, Discovery Dish and Discovery Drive

Over on the Saveitforparts YouTube channel, Gabe has documented how he accidentally discovered signals coming from the GPS-satellite-based US nuclear detection system.

While scanning the GPS L3 frequency around 1381 MHz with his RTL-SDR, Discovery Dish, 1420 MHz Hydrogen line Discovery Dish feed, and Discovery Drive, Gabe caught short intermittent data bursts instead of the usual navigation signals. It turns out L3 is used by the GPS constellation for nuclear detonation detection, as the satellites double as arms-control sensors. When one detects a possible event, it relays the message across the network, the only time this frequency sees activity.

Later in the video, Gabe also swaps the dish feed to compare against a regular GPS L1 signal at 1575.42 MHz, and notes that radio astronomers are reverse-engineering L3 to filter it out, since it sits close to the protected 1420 MHz hydrogen line.

I Found The US Nuclear Detection System In Space

Further Tutorials on SatDump Map Projections

Thank you to Paul Maine, who has submitted to us two new SatDump tutorials that he has uploaded to his YouTube channel. These two tutorials follow on from his previous tutorials that we posted a month ago.

His SatDump V2.x Part 5 video demonstrates Recording and Processing. Paul shows his hardware setup and then shows GUI Live Processing, CLI Live Processing, CLI Recording and how to use the GUI to process recorded files.

E28 SatDump v2.x Part5 Recording & Processing

His SatDump V2.x Part 6 video on Projections introduces Map Projections. Paul uses things covered in earlier SatDump videos and builds upon them to create very interesting map projections. For his first example, he uses the Load First Party feature to download a GOES-19 CONUS image. Next, he shows how to add a shape file and a Severe Storms image expression. Lastly, he shows how to create an equirectangular map projection. In the video, Paul also shows how to create three other types of projections.

Before SatDump Projection
Before SatDump Projection
After SatDump Projection
After SatDump Projection
E29 SatDump v2.x Part 6 Projections

Saveitforparts: Seeing Satellites with the Discovery Drive and Discovery Dish

Over on YouTube, Gabe from the saveitforparts channel has uploaded a video where he tests out his Discovery Drive and Discovery Dish with L-Band feed for creating sky heatmaps of L-band satellites.

If you were unaware, Discovery Drive is our sister company KrakenRF's most recent successful crowdfunding campaign, which was successfully funded a couple of weeks ago. Discovery Drive is a portable antenna rotator with low power requirements, designed for use with Discovery Dish and other antennas of similar size and weight.

In the video, Gabe writes a custom script that has the Discovery Drive sweep the sky while simultaneously taking RF power readings with the Discovery Dish and L-band feed. The result is an image showing where L-band satellites are in the sky. He goes on to conduct experiments with the hydrogen line and sun imaging, as well as with satellites at UHF frequencies.

Seeing Satellites With The Discovery Drive