Developing a VHF+ Reverse Beacon Network Brian Jacobs ZS6YZ Unlocking amateuR radio technology

Developing a VHF+ Reverse Beacon Network Background Beacons Why a Reverse Beacon Network What is it What can it do for us Where to from here Unlocking Amateur Radio Technology

Developing a VHF+ Reverse Beacon Network Background Appoint a VHF Manager / Beacon Co-ordinator for VHF and Above ✓ Put a workgroup together to run with the project ✓ Get a definitive list of current active VHF/UHF beacons ✓ Convert to IARU recommendations Start building a Beacon Monitoring System

Developing a VHF+ Reverse Beacon Network What is a Beacon? A transmitter sending out periodic omnidirectional signal 24/7 for the purpose of doing propagation research. A beacon can send out a CW or MGM signal.

Developing a VHF+ Reverse Beacon Network Why is a Beacon Important? Reception of a beacon signal is an indicator that a RF path is open in a certain direction. When and where a beacon is received will allow amateurs to study propagation in order to better understand it.

Developing a VHF+ Reverse Beacon Network Start building a Beacon Monitoring System It started with a question from Hans ZS6AKV? I have an idea based on the HF reverse beacon principle. Say we target 2m. Set up a SDR dongle receiver and antenna at the NARC and programme beacons and calling frequencies. The software scans any signals and records the info and sends it to a website. So we can check when openings are happening, etc.

Developing a VHF+ Reverse Beacon Network Start building a Beacon Monitoring System And the answer was ... Did a quick search on the WWW. John Ackermann N8UR was asked a similar question by Bob K8TQK. John provided a possible solution in a presentation dated April 2018. Everything needed already exists out there. No need to re-invent the wheel.

Developing a VHF+ Reverse Beacon Network Start building a Beacon Monitoring System What exists out there DXMaps is a widely used web site that shows QSOs reported by Clusters and Reverse Beacon Network. http://www.dxmaps.com

Developing a VHF+ Reverse Beacon Network Start building a Beacon Monitoring System What exists out there Reverse Beacon Network (RBN) is a web site that collects data reported by any Radios feeding CW Skimmer (and other similar) software. http://reversebeacon.net

Developing a VHF+ Reverse Beacon Network Start building a Beacon Monitoring System Why a Reverse Beacon Network? Instead of only beacons actively transmitting signals, the RBN is a network of stations listening to the bands and reporting what stations they hear, when and how well. You can see band openings in near-real time on an animated map. You can call a quick CQ, and see which reverse beacons hear you, and how strong you are.

Developing a VHF+ Reverse Beacon Network Start building a Beacon Monitoring System Why a Reverse Beacon Network? There is a database of past "spots". You can instantly find out what stations, from a given country or zone, have been heard, at what times and on what frequencies. You can compare your signal with those of other stations in near real time or historically. The Signal Comparison Tool will give you real, quantitative data. Tell it what stations you want to compare, based on signals heard by a given reverse beacon on a certain band at a certain time.

Developing a VHF+ Reverse Beacon Network Start building a Beacon Monitoring System Why a Reverse Beacon Network? Bands available 137kHz to 13cm. Modes CW, RTTY, PSK31, BPSK & FT8. Decent HF coverage in North America and Europe. Very few VHF+ stations. Why? The Reverse Beacon Network depends on volunteer stations.

Developing a VHF+ Reverse Beacon Network Start building a Beacon Monitoring System How does it Work? CW Skimmer decodes CW signals, looks for CQing stations, and sends reports to the RBN. Windows program by Alex, VE3NEA ($75 license fee) Spots include time, freq, speed, and signal-to-noise ratio. Skimmer Server supports up to 8 x 192 kHz band segments Skimmer does CW, and there are also versions that decode RTTY and PSK modes. Aggregator software forwards Skimmer spots to a central RBN server. Central server distributes spots via web page and public telnet servers.

Developing a VHF+ Reverse Beacon Network Start building a Beacon Monitoring System N8UR Proposed Solution Low Cost SDR Receiver Dongle-to-Skimmer Interface Skimmer doesn’t directly support RTL-SDR dongle But N1GP “rtl_hpsdr” software on Raspberry Pi gives us a “shim” between dongle and Skimmer. Up to 7 dongles on USB Emulates HPSDR on Ethernet Makes multiple dongles look like one multi-band HPSDR.

Developing a VHF+ Reverse Beacon Network Start building a Beacon Monitoring System Complete Receiver

Developing a VHF+ Reverse Beacon Network Start building a Beacon Monitoring System Built a Proof of Concept System N1GP “rtl_hpsdr” software on Raspberry Pi is configured to emulate the Hermes / Mercury HPSDR receiver. Hermes receiver coverage from 10kHz to 55MHz Not a VHF+ solution !!!!

Developing a VHF+ Reverse Beacon Network Where to from here? Other Possible Solutions Short Term - Windows Laptop CW Skimmer Aggregater Single Dongle Solution Longer Term - Develop Raspberry Pi Solution with alerting via Telegram App

Developing a VHF+ Reverse Beacon Network Is monitoring of the beacons the only option? What about... APRS signals inland 144.800 MHz AIS (automatic identification system) signals along the coast 161.975 & 162.025 MHz ACARS (Aircraft Communications Addressing and Reporting System) 131.500 MHz ADS-B (Automatic Dependent Surveillance- Broadcast) 1090 MHz

Developing a VHF+ Reverse Beacon Network Thank You Questions? Unlocking amateuR radio technology