Tagged: NTSC

VMA Radio Lab: DecSAT Extended into a Multi-SDR Receiver with DVB-T/T2, DAB+ and Analog PAL TV

Last week we posted about DecSAT, an open-source program by CasualArclamp that turns a HackRF One into a DVB-S/S2/S2X satellite receiver and analyzer. Now Vitor Martins Augusto has written to share his fork, 'VMA Radio Lab' (initially called DecSAT-VMA), which extends DecSAT into a general-purpose broadcast receiver and measurement tool.

The biggest difference between DecSAT and VMA Radio Lab is multi-SDR operation. VMA Radio Lab can run several SDRs at once, each with its own VFOs, including the HackRF, PlutoSDR, USRP B210, RTL-SDR, SDRplay RSP1 and Airspy. One SDR can be dedicated to a sweeping wideband overview, such as the full 950 - 2150 MHz satellite IF. It also pulls in DVB-T/T2, DAB/DAB+ and TETRA decoding from CasualArclamp's sibling projects DecDVB-T, DecDAB and DecLAB, and adds analog radio, PAL color TV with teletext, measurement tools such as a vectorscope and transport stream analyzer, and control of CrazyScan-compatible TBS tuner cards for LNB power and hardware DVB reception.

Meanwhile, the original DecSAT remains satellite-focused. Since our last post it has added support for Fobos SDR, Airspy and network IQ input (including rtl_tcp), and has merged some of VMA's early RTL-SDR, PlutoSDR, B210 and analog TV code.

VMA Radio Lab is GPLv3 and available as a Windows 64-bit build and source zip on the website. We note that TETRA audio needs a separate ACELP codec DLL that isn't included for legal licensing reasons, and the bundled development notes describe several of the newer decoders, such as AIS and ACARS, as experimental. 

Decscat-VMA Screenshot
Decscat-VMA Screenshot

AI Disclaimer: The original DecSAT lists Claude as a contributor. While VMA does not disclose it, the development notes included with the VMA Radio Lab source suggest that its extensions were also written with the help of AI.

Muxwright: A Multi-Standard Radio and TV Test Transmitter for the PlutoSDR

Thank you to Peter Holzhauser for writing in and sharing Muxwright, a multi-standard radio and TV test transmitter for the ADALM-Pluto (PlutoSDR). Peter has in the past submitted his ESPSoup, and Etherbulb projects. Muxwright is intended for home lab testing only, with the Pluto connected to the receiver under test via cable and attenuator or inside a shielded box, as radiating broadcast standards over the air requires a frequency assignment.

Muxwright can generate FM stereo with RDS/RBDS, DAB+, DVB-T, DVB-T2, DVB-C, DVB-S/S2, ATSC 1.0, ISDB-T, DTMB and analog PAL/NTSC TV, plus DVB-S2 DATV for QO-100 and other amateur bands (which of course requires an amateur radio license). The digital TV modulators run directly on the Pluto and everything is controlled from a browser dashboard. The Pluto's RX input can also be used as a monitoring receiver for expected vs. actual test reports.

The software runs on Windows 10/11 via WSL2 and is currently at Beta 0.4. The README notes that it has only been verified on the original Pluto Rev. B, and that DVB-T2, ATSC, ISDB-T and DTMB are still untested with real TV sets. The code is MIT licensed (with the FM/RDS module under GPL-3.0) and available on GitHub, however, the Windows installer is only available by request via email from the website.

Muxwright Transmitting DVB-T with a PlutoSDR
Muxwright Transmitting DVB-T with a PlutoSDR

AI Disclaimer: The project's GitHub commit history lists Claude as a co-author.

OnAir: A Digital TV and DAB Decoder for SDRs

Thank you to Kristijonas for writing in and sharing with us his project, OnAir. OnAir is an easy-to-use digital TV decoder for DVB-T2, DVB-T, ATSC 1.0, ATSC 3.0, ISDB-T, and a digital audio decoder for DAB / DAB+ and FM Radio. It also supports Analog TV modes such as PAL, SECAM, and NTSC, and data modes like ADS-B, GNSS (GPS, GLONASS, BeiDou), and DMR.

It supports various wideband SDRs, including HackRF, PlutoSDR, BladeRF, LimeSDR, USRP, Airspy R2, and SDRplay. RTL-SDRs unfortunately do not have enough bandwidth to decode digital TV channels in SDR mode, but the software still supports RTL-SDRs for narrowband signals.

The software is easy to install, with an installer .exe being available for Windows, a .deb file for Debian Linux, and a .dmg file for macOS. 

OnAir Screenshot
OnAir Screenshot

AI Disclaimer: This software lists Claude as a contributor.

SignalsEverywhere Software and Video Updates: Benshi Dash, AI Vibe Coding SDR Apps, Android NTSC Receiver, NOAA SAME Encoder

Thank you to SignalsEverywhere, aka Sarah Rose, for writing in and sharing some updates on what she's been working on recently.

First, Sarah provides an updated video that shows off her Benshi Dash Android application (GithHub, Name-Your-Price Store Download) for VR N76, UV Pro, and other similar handheld radios with Bluetooth connectivity. 

Benshi Dash | The Ultimate Radio Dashboard for VR-N76 UV-PRO Etc

Next, she notes that she uploaded a video showing the power of Google's Gemini AI, and how she was able to use it to vibe code a HackRF TV transmitter program on Linux in just a few minutes.

Vibe Coding a TV Transmitter on Linux with a HackRF

Next, she mentions that she also built an RTL-SDR NTSC Receiver for Android, based on the TVSharp decoder. It is available on GitHub and via her name-your-price store, with a $0.00 minimum spend. 

RTL-TV. An NTSC video decoder for Android and RTL-SDR.
RTL-TV. An NTSC video decoder for Android and RTL-SDR.

Finally, Sarah writes that she has also created a NOAA SAME weather encoder for use with a HackRF on Linux or Android. This allows users to transmit NOAA SAME (Specific Area Message Encoding) alerts, which are weather alerts typically transmitted on the NOAA Weather Radio frequency, transmitted around 162 MHz. The software is available via GitHub, or via her store for $10 (Linux edition / Android edition).

NOAA SAME Transmitter
NOAA SAME Transmitter

SignalsEverywhere Android Project Updates: Satellite Tracker, HackTV NTSC Transmitter, OBS To HackTV, PacketShare and More

Recently, Sarah Rose Giddings (aka SignalsEverywhere) has been actively developing several radio and SDR based projects for Android, and she would like to provide an update on them.

First, as mentioned in a previous post, Sarah has been developing APRS.chat, an online mailbox system for APRS messages sent over RF. She has also been making progress on various other projects, including various useful Android apps, which she has updated interested people on in her latest livestream.

Hangout Chat | Linux | HackRF NTSC Transmission | Android APPS and More!

Some of the links to the Android software she's working on have been provided below:

Works with Benshi Protocol Radios (VR-N76 UV-PRO etc)

Stuff Created After The Livestream

Help beta test Play Store Releases (Benshi Dash, Benshi Commander, APRS Chat): https://docs.google.com/forms/d/e/1FAIpQLSfNTrCBofQYam6f6CrZ8XxTxZw2vlOiaD6ehGs5NBOAbKkHWw/viewform?usp=header

Screenshots from Sarah's HackTV NTSC Transmitter
Screenshots from Sarah's HackTV NTSC Transmitter

uAVD: Analog Video Decoder Windows Software for SDRs

Thank yoy to Viol Tailer for submitting news about the release of his new software called "uAVD - Analog Video Decoder". uAVD is capable of demodulating the following:

  • AM (broadcast analog television - NTSC, PAL, SECAM)
  • FM (FPV drone video links)
  • RAW (composite output from VHS, camcorders, game consoles)

The software uses the uSDR software as a host, and it passes the IQ passband stream to the uAVD via a uSDR-TCP link. uSDR is a lightweight general purpose multimode software defined radio receiver Windows application that we have posted about on the blog in the past. Currently, it supports RTL-SDR, AirSpy, BladeRF, HackRF, FobosSDR, and LimeSDR devices.

The software supports full color and grayscale modes. With a wideband receiver, it will be possible to receive full-color video. With the reduced bandwidth available with an RTL-SDR, only grayscale will be available.

The code is not open-source, but the software is freely available from SourceForge.

The image below shows it being used to receive video from a camcorder composite video output. A FobosSDR used in direct sampling mode is used to receive the signal.

uAVD Receiving Camcorder Composite Video via the Direct Sampling Input in FobosSDR
uAVD Receiving Camcorder Composite Video via the Direct Sampling Input in FobosSDR

Below is a video from a user of the software demonstrating it in action.

uSDR and uAVD analog video decoder

SignalsEverywhere: Using HackTV to Transmit Analog Television with a HackRF

Over on her YouTube channel SignalsEverywhere, Sarah has uploaded a new video showing how to use a program called 'hacktv-gui' to transmit analog TV signals using a HackRF software defined radio. Analog TV standards such as PAL and NTSC have been phased out in most of the world in favor of digital TV standards instead. However, transmitting these yourself can be a fun experiment that may help breathe life into old television sets.

In the video Sarah explains how to use the hacktv-gui and hacktv software, and how to create a video transmission. She mentions how hacktv also supports the use of a FL2K device, which is a cheap VGA adapter that can be used to transmit signals.

HackTV | Analog Television Transmission with a HackRF SDR

Decoding the RF Output of a VCR with an RTL-SDR

Over on YouTube use Scelly has uploaded a video showing how he has used an RTL-SDR dongle and the TVSharp SDR# plugin to decode video from the RF output of an old VCR (videocassette recorder). VCR players were designed to output the same PAL or NTSC signal that old analog TV transmissions used, and the RF output of the VCR was connected directly to the TV's antenna input.

The TVSharp plugin for SDR# can be used to decode these signals, however as the bandwidth of PAL/NTSC signals is much larger than the 2.4 MHz provided by the RTL-SDR, only a black and white image can be received. Scelly writes:

RF Output from VCR connected directly to input of my RTL-SDR. The RF output is tuned to channel 22 (487.25 MHz), and as the signal is so wide, my RTL-SDR can only display the luminance data (black and white video) and audio, although not at the same time. If I had two RTL-SDRs or an SDR with a larger bandwidth, I could have both audio and video playing at the same time.

The video playing is "The Prince of Egypt" on VHS Video Cassette.

Decoding RF Output of a VCR with RTL-SDR Dongle