Ambientscape WebSDR

....Ambientscape WebSDR....

@ The Crystal Radio Receiver Earth Station

WEBSDR.AMBISERVE.COM

Through OpenWebRX+

(Maintenance work from Jan 13th-Jan 19th)

'Listen to Live Radio Transmissions from Earth and Space'

Based in Harrow the Ambientscape WebSDR is a radio receiver comprised of an RTL-SDR, SDRplay and HackRF Software-Defined Radio from a mobile Receive Only Earth Station. It runs on a low power reused Raspberry Pi server with a solar panel and renewable battery backup. This WebSDR is intended to be an educational tool for those that may have an interest in amateur radio or satellite communication.

Radio is a mode for transmitting and receiving electromagnetic waves of radio frequencies especially those carrying sound messages. Software-Defined Radio (SDR) is a radio communication system where components that have been implemented in earlier analog hardware e.g. amplifiers, mixers, filters, modulators/demodulators are instead implemented by means of software on a computer or embedded system which performs the radio signalling process.

A WebSDR is a Software-Defined Radio Receiver connected to the internet which allows many users to listen to and tune a radio simultaneously. The WebSDR provides listeners with a way of hearing or recording radio audio signals through antennas based at the Ambientscape Crystal Radio Receiver Earth Station and to experience the method of tuning a receiver using software.

The Software Defined Radio is popular in the field of radio astronomy where it can be utilised as a radio telescope together with suitable antennas, low-noise amplifiers and filters to detect phenomena such as hydrogen line emissions in the Milky Way and meteor scatter.

The Ambientscape WebSDR may be used to capture experimental live radio sound effects during frequency shifting, modulation or filtering. Scanning VHF, UHF or HF to listen to Ham radio operators and to receive voice transmissions or SSTV data from the ISS (International Space Station). Downlink data from the Senegal GaindeSat nanosatellite can also be heard for Earth Observation (EO). Sound does not travel in space and so encoded radio waves are used for communicating between the transmitter and receiver.

SDR Devices: RTL-SDR, SDRplay, HackRF

Web Server: Raspberry Pi

Software: OpenWebRX+ Web Based SDR Receiver on Linux Ubuntu 22.04

Antennas: Sirio GP 1/4 Wave Ground Plane, Scan King Discone, Magnetic Longwire Balun

Scanning Modes:

2M Band (VHF) 143.980 MHz to 146.020 MHz (RTL-SDR), 1/4 Wave Ground Plane

10M Band (HF) 27.857 MHz to 29.844 MHz (SDRplay) SPX100 Telescopic Antenna

20M Band (HF) 13.131 MHz to 15.221 MHz (HackRF) 9:1 Magnetic Longwire Balun

Meteorological (UHF) 400 MHz to 450MHz (RTL-SDR), Scan King Discone Antenna

Click to run the Ambientscape WebSDR through your web browser

Read instructions on how to use the OpenWebRX+ web based software

What is the ISS?

The I.S.S. International Space Staion is a large low orbiting spacecraft and home to a crew of astronauts and cosmonauts. It orbits the Earth at a height of 250 miles, 16 times a day, at a speed of 28,000 km/h and is the largest orbiting laboratory and observatory for scientific research. The ISS is used for researching space technology and a platform for STEM education.

As of October 2024 there are 10 astronauts in space:

International Space Station, Starliner CFT - Butch Wilmore, Sunita Williams

International Space Station, SOYUZ MS-26 - Don Pettit, Alexey Ovchinin, Ivan Vagner

International Space Station, SpaceX Crew-9 - Nick Hague, Aleksandr Gorbunov

Tiangong Space Station, Shenzhou 19 - Cai Xuzhe, Song Lingdong, Wang Haoze

Listen to Astronauts from the ISS International Space Station

Step 1: Locate the ISS Satellite

Track passing satellite with AMSAT Online Satellite Pass Predictor using the coordinates below

Station Coordinates:

Gridsquare: IO91to

Latitude: 51.6042

Longitude: 0.375

Elevation: 53M

Click to Convert (UTC) time zone to your local country time zone using the calculator

Step 2: Tune SDR to Correct Frequency

Tune the Ambientscape WebSDR on 2M, 145.800 MHz to hear I.S.S. voice transmissions

Wait for next predicted pass overhead using timings from Online Satellite Pass Predictor

Other Considerations:

Range and Schedule

The ISS is in range 5-6 times a day for a maximum of 10 mins, transmission schedules vary.

Doppler Effect

When the ISS is approaching transmit frequency of 145.800 may appear 3.5KHz higher

(145.803), as the ISS moves out of range the frequency will then shift down to 145.796,

Ambientscape WebSDR can be tuned to follow and compensate for the changes.

(Optional) SSTV Audio to Image Decoding

Tune the Ambientscape WebSDR on 2M, 145.800 MHz to hear SSTV data audio tones

Click to download Robot36 decoding software on Android device

Click to download MMSTV decoding software on Windows system

Playback live or recorded SSTV data tones directly to Robot36 or MMSTV to decode audio

The Importance of African Space Satellites

There are at least 26 satellites orbiting the Earth from the African continent including those deployed to monitor the environment, assessing agricultural yields, checking water/air quality, observing the weather climate, tracing forest health and preventing illegal mining.

GaindeSat-1A

Senegal launched its first satellite on the 16th August 2024 at 7.56pm BST. The nanosatellite was built over the course of 3 years by Senegalese engineers and technicians with the latter trained at Centre Spatial Universitaire Montpellier in partnership with the Senegal government. GaindeSat

is an Earth observation satellite for environmental data gathering in particular water resources weather forecasting and the monitoring of Senegal's lakes and watercourses.

Receive Transmitted Data Audio from GaindeSat-1A

Step 1: Locate the GaindeSat-1A Satellite

Track Passing satellite with AMSAT Online Satellite Pass Predictor using the coordinates below