Notes about the video meetings
Saturday 17 October 2020, 20:00 UTC
After some technical difficulties with Big Blue Button, we moved to Zoom and succeeded in doing the planned agenda:
- Brief walk-through of Simulation example: FSK
- Presentation of gr-RTTY-basics package
- Audio loopback demo
- Live Over-the-Air demo
The time (20:00 UTC) proved to be too late for participants East of Greenwich, so an earlier one was scheduled for 7 November.
Saturday 7 November 16:00 UTC
The meeting followed the agenda above. There was a minor audio difficulty with the loopback, but I proceeded to present the Over-the-Air demo successfully.
View the presentation on https://www.youtube.com/watch?v=_HmbRk-UG8Q
Saturday 12 December 2020 16:00 UTC
Subject: Transmit / Receive switching and station control
Presenter: Gavin Jacobs VE7GSJ
- Requirements for TX/RX switching
- VE7GSJ Solution (hardware & GNURadio Companion)
- Demo on 2m repeater
Thanks to Gavin for an excellent talk. It can be viewed at https://www.youtube.com/watch?v=rTp6vQk5MqE
16 January 2021 16:00 UTC
Subject: Using GRC to build radios: Make the flow graph work for you
Presenter: John Petrich W7FU
- Getting started with GRC
- Basic flow graph workspace organization
- Flow graph details
- Data flow problem solving
- Practical odds and ends for real radios
- Group discussion
Thank you to John for a very informative presentation. It can be seen at https://youtu.be/j8OeK7c_zAU
27 February 2021 16:00 UTC
Subject: A Look at Project 25 (P25) Digital Radio
Presenter: Aaron Rossetto, NI
Agenda: In this presentation, I will introduce Project 25 digital radio, with a strong emphasis on its use in North American public safety trunked radio systems, and to describe experiments monitoring and decoding P25 traffic using GNU Radio code.
- What is Project 25?
- A brief introduction to trunked radio
- Diving into the P25 protocol
- Packet framing and encapsulation
- Packet types
- GNU Radio and P25 decoding experiments
Presentation slides: Media:A_Look_at_Project_25_(P25)_Digital_Radio.pdf
Thank you to Aaron for an in-depth presentation. The video can be seen at https://youtu.be/9_Bb7g3_-7E
20 March 2021 16:00 UTC
Remember that Daylight Saving Time will have started in the U.S.
Subject: Ground Station Test Transceiver
Presenter: Ray Roberge WA1CYB
- What is this Ground Station Test Transceiver ?
- Architecture – Three Sections
- Receiver flowgraph
- Transmitter flowgraph
- Telemetry flowgraph
- GUI displayed with a ADALM Pluto SDR
- Over the Air results as received on a ETTUS B205mini on SDR-Console software
- Discussion on finer points of Packet telemetry
- Same flowgraph modified for UHD, Ettus B205mini and why you need to modify it
- QT display , GRC 3.8.2 / 3.8.0 minor issues noted
- Ground Station Test Transceiver.pdf
- These and other supporting files can be found at 
Questions and Suggestions for future meetings
- The Ham Radio chat room on Matrix is available for follow-up and continuing discussion.
- server: https://chat.gnuradio.org
- or via the Homeserver in a matrix app: gnuradio.matrix.ungleich.cloud
- room: #HamRadio:gnuradio.org
- Questions about meetings also can be sent to "firstname.lastname@example.org"
- Transmit hardware to operate below 50 MHz.
- amateur radio satellite service
- Contact ISS
- EME - moon bounce communications
- How to implement JS8, JS8-Call, and FT8 in GR
- An in-depth walkthrough of GQRX
- How ZMQ sockets work